M8000 brake "pumping up" on DH- Mtbr.com
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  1. #1
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    M8000 brake "pumping up" on DH

    I recently had the new 2016 shimano m8000's installed and I am having some issues when going through rough sections of trail. With fingers on the levers, I can feel them pump up when I go thru fast rough sections and DH sections. The bite point changes drastically and yesterday had a minor crash because of it. I think they locked up on me when I had them feathered and pointed the bike down a vertical drop. I haven't done any work on these yet, I normally install & bleed my own brakes but I had a shop install these because I was too busy that week. Nothing like this ever on the m785's which I still have on 2 other bikes.
    Anyone else have similar experience?

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    I'm interested to hear what the solution is. This constantly happened on my 785s over two years with multiple bleeds. Couldn't live with the inconsistency so I got new brakes.

  3. #3
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    I've heard of this, haven't experienced it with my M785s or M987s.

    When you say "pumping up", that usually refers to one of two things: The engagement point moving out, to the point where the brake will eventually just lock up without even pulling the lever. Older closed-system hydraulics did this and my Formula C1 seemed to require a "reset" after hard braking where the fluid expanded due to heat, something I suspect due to how they designed the reservoir to interact with the lever-pull.

    The other "pumping" that people often refer to is a lack of power, where the lever goes to the bar, or at least the engagement point is far in, and you have to "pump" the brakes several times to either get an engagement point, or move it away from the handlebar to where you can get good "bite". This is almost always air in the lines/system. I had this one while bleeding my M987s a few weeks ago and I am pretty sure I know what did it during my bleed. I fixed it and the brakes work great.

    Which of these are you describing?
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  4. #4
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    The pumping up that I experienced was the engagement point moving out and I would have to let go of the brake and reapply for it to be back to the normal engagement point. Not so much where it would brake without pulling the lever, but a lot sooner than it normally would. This typically happened when going down critical parts of the trail where I would be rapidly braking on and off.

  5. #5
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    The levers move out when lightly feathered.
    When cold, it does it over rough trail. When hot it locked up on me rolling down a steep 5 ft drop. I went over the bars and couldn't figure out what the hell just happened. I just did the same drop the day before with my other bike with no issue. I realized it was the brakes. For once I can blame the bike, lol.
    But seriously, this scared the crap out of me. I've adjusted the levers way back now. I don't know how the bite point screw works, but willing to give that a try.

    Is this just a bleeding issue? They are brand new and bled, I don't get it.

  6. #6
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    If the point is moving out, it either means bad fluid (what kind was used?) or the internal reservoir that adjusts for heat expansion isn't functioning correctly.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

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  7. #7
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    Hmmm, I've never bled them , they were done when the hoses were cut down and Shimano fluid was used. Only a few rides on them and they have "pumped up" every time I go through a rock garden or heavily rutted sections (both front & rear do this). A quick release will usually "reset" them, but that is not always the ideal thing to do in certain situations (like setting up for a corner). I've got the saints on my DH bike and they never do this, even though the levers are similar in design.

    I have adjusted the levers in a bit so when it happens i have some room to release them and not lock up the brake. I also turned the bite point screw 1/2 a turn outwards. Not really sure what that does. It's a bit better now, but next step is a full system bleed and reevaluation. There doesn't feel like there is any air in the lines

  8. #8
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    It's air trapped in the caliper.
    Brakes will feel fine and lever can feel firm and consistent on flat terrain, but point the bike down something very steep or hit high speed chunk requiring you to vary the pressure applied to the lever and you'll feel exactly what you are describing.
    Bleed your Shimano brakes this way:
    https://www.youtube.com/watch?v=T1WT5EkJ9Qs

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    Humm, I just put on a rear m8000 without cutting the hose. It says it's pre bled. I experience a tad up pumping up, but it was immediately alleviated when I released the lever and pull it again.

    It was on a dh, but not really steep or anything like that. The lever felt like it was at it furthest reach point setting. My setting has it closer to the bars.

    I will have to cut my hose at some point soon. So I will have to see if the problem persists after the hose cut and rebleed
    Lead by my Lefty............... right down the trail, no brakes.

  10. #10
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    I've tried the bleed hanging off my bike to get it as vertical as possible as well as angling the lever in multiple positions to get every possible bubble out. Never worked. I gave up and got guides.

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    I think I figured our why Jared Graves runs the old xtr levers. The new design (shared by the saints, xt and xtr) levers are absolutely crap.
    I just talked with another guy who had all the same symptoms I described earlier. He races enduro and DH, knows exactly what I'm talking about. I'm putting some old m785 levers on and selling the m8000 levers. Totally disappointed, no wonder they are so cheap, they are a defective design.

    I'll bleed them by taking them off the bike and hanging vertical. It's the only way left to try. I've watched the shimano video many times before, I've got the bleed cups, everything, and been doing it for years now. But hanging them vertical guarantees a perfect bleed. If that does not solve it nothing will. I'll get back with my results later this week.

  12. #12
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    I had a similar problem with avid brakes, turned out to be water contamination.
    needed to flush all the fluid out a bleed does nothing.

  13. #13
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    ....brand new brakes, fresh bleed, no air, no water contamination. IDK. One last chance and then they're going on ebay.

  14. #14
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    I will say my problem is not a deal breaker really. Sure I had a few pump ups here and there, but the issues resolved from my formula RX counter things. I skid way less which means I have better control. One of my long dh runs where I seemed to overheat the brakes, didn't happen.

    DOT fluid. While I did not really have any issue with bleeds, I was alway irked at buying new fluid every time.

    I think we are in the same old boat we have always been in. No system is perfect. Each one has it's pros and cons. You have to choose what you are willing to put up with.

    My current tolerance is for the M8000. I reserve the right to change my mind and have someone on this thread buy me beer at anytime.
    Lead by my Lefty............... right down the trail, no brakes.

  15. #15
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    I had this problem when running the organic pads that came with the set on my rear brake. The inconsistent bite point got really bad on one muddy DH intensive ride and noticed at the end the inner pad was almost down to the backing plate while the outer pad was fine.

    Turns out that outer piston wasn't moving freely. So I took my pads and wheel off and pumped the pistons out a bit and cleaned em off then sprayed the piston seals down with finish line max suspension spray. (hey if it works on fork seals that are designed to seal in mineral based suspension fluid why wouldn't work on my brakes). After spraying em down I worked the pistons back and forth for a bit then cleaned everything off with some rubbing alcohol and put some sintered Ice tech pads in. So far so good even on rides with significantly worse dowhills.

  16. #16
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    I backed out the free stroke screw, dialed in the levers a bit so there is room when it happens again, so I'm hoping I don't inadvertently grab a handful of front brake again when the lever moves out on me. BTW, I always have new pads on it, they get changed at 50%

    Havent had time to fully replace the fluid yet, I've been busy upgrading my other bike for racing Enduro (dialing it in & keeping the M785's on there) and had no time to deal with it. The FreeRide bike the m8000's are on will get alot of use this winter now the bikeparks are closed, so it's a must to fix the problem.
    I've got 2 brand new XT M785 levers for it if the next bleed doesn't work. I don't think it's the calipers causing the problem.

  17. #17
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    I've got the same problem with a new set of M8000s. It is very disappointing.
    I've bled the rear twice. The second time I unscrewed the caliper from the frame to make the line vertical. I also repositioned the lever a number of times to facilitate the best bleed. I took my time, but ended up seeing the same results: frequent feathering, especially when pointed downhill, leads to a pumped up lever that results in a full on/off feel. I've played with freestroke and lever reach a bit, which helps, but it is far from optimal.
    This is not what I had in mind when I ponied up for the new model.
    This has never been an issue with the two sets of M785s that I've run. One pair, which I just picked up at a blowout price of $122 shipped, feels worlds better with organic pads and factory bleed.
    I'm ready to replace the M8000's, but am kicking myself for getting the ispec shifter that matches the new brake's clamp, so I'm on the hook for a rear shifter too.
    I know that shimano has had its share of boners over the years, but their brakes have been the standard for quite some time now. I'll be watching this thread closely for any intel on how to deal with the issue.


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  18. #18
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    I had this issue on one of my M8000 brakes when there was a small amount of air in the system. Since burping the air out and topping it up the issue has disappeared.

  19. #19
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    interesting. i've just purchased my m8000 set, but haven't gone a full off road test yet...

    however, i did notice that the levers can be pushed out away from the grips? it's like this, brake levers are pulled towards the grips to engage, but i noticed that they can also be pushed away (obviously it doesn't engage the pads), but yea, is this normal for an m8000 levers (both rr/fr)?

  20. #20
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    Try bleeding with the free stroke screw backed out completely and also watch out for air trapped behind the pistons. My rear Saint 820 had issues until all the air was removed, which only happened by backing out the free bleed screw and pumping out the pistons a bit during the bleed process, has been flawless ever since.

  21. #21
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    Quote Originally Posted by idontcare View Post
    Try bleeding with the free stroke screw backed out completely and also watch out for air trapped behind the pistons. My rear Saint 820 had issues until all the air was removed, which only happened by backing out the free bleed screw and pumping out the pistons a bit during the bleed process, has been flawless ever since.
    shimano manual says that the free stroke should be "all the way in"
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  22. #22
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    It should be in for the final bleed, and the piston block should also be used for the final bleed, but to ensure all the air is out of the system, it is helpful to do the above. The screw needs to be all the way in and the pistons blocked before closing the system to ensure proper fluid volume. Air was definitely trapped in my system and was only released after backing out the free stroke screw.

  23. #23
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    Quote Originally Posted by idontcare View Post
    It should be in for the final bleed, and the piston block should also be used for the final bleed, but to ensure all the air is out of the system, it is helpful to do the above. The screw needs to be all the way in and the pistons blocked before closing the system to ensure proper fluid volume. Air was definitely trapped in my system and was only released after backing out the free stroke screw.
    sorry, i didnt quite get that 'final bleed,' and at which point should the screw be backed out completely if it should be in?
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  24. #24
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    I have had the M8000 for less than a month and so far a huge disappointment. I think the issue you (we) are having is air in the system. I have done 2 bleeds so far and they still suck, but improved a little over the first bleed. the adjustment screw is totally worthless. You get on try on it and the notches in the screw head are totally rounded out and it doesn't change anything. These are by far the worst aftermarket brakes I have purchased. I put my low level doer back on the front because the massive clamp on the M8000 makes it very difficult to place anything next to it one the bar, e.g., GD switch. I am too lazy to send them back now so the front will be going on Craigslist soon. I will keep working on the rear to bleed properly. Funny, I have no issues bleeding doer or SLX, which I have on other bikes, but getting the air out of the M8000 is not as easy.

  25. #25
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    Quote Originally Posted by spyghost View Post
    sorry, i didnt quite get that 'final bleed,' and at which point should the screw be backed out completely if it should be in?
    Sorry for the confusion. To help dislodge air (potentially) trapped behind the free stroke adjuster and pistons, try backing out the screw and extending the pistons. Once the air is out of the system, then screw in the screw, push in the pistons, use the bleed block and follow the Shimano procedure.

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    Quote Originally Posted by idontcare View Post
    Sorry for the confusion. To help dislodge air (potentially) trapped behind the free stroke adjuster and pistons, try backing out the screw and extending the pistons. Once the air is out of the system, then screw in the screw, push in the pistons, use the bleed block and follow the Shimano procedure.
    ok, so for this stage, what is the 'bleed' setup?

    for shimano, the bleed steps are broken down into various steps
    1 - funnel on lever, fluid injected from caliper
    2 - plastic with tube on caliper, fluid pushed from lever
    3 - caliper port closed, lever depressed and rotated with bleed funnel

    in all 3 major steps (so to speak), the bleed block is between the pistons.

    still confused (sorry) as to which part the one in bold above comes in?

  27. #27
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    Quote Originally Posted by spyghost View Post
    ok, so for this stage, what is the 'bleed' setup?

    for shimano, the bleed steps are broken down into various steps
    1 - funnel on lever, fluid injected from caliper
    2 - plastic with tube on caliper, fluid pushed from lever
    3 - caliper port closed, lever depressed and rotated with bleed funnel

    in all 3 major steps (so to speak), the bleed block is between the pistons.

    still confused (sorry) as to which part the one in bold above comes in?
    This thread will explain everything you need:

    http://forums.mtbr.com/brake-time/xt...-950178-2.html

    Hope it helps.

  28. #28
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    M8000 brake "pumping up" on DH

    tnx.

    i've done a full bleed and did a road test (no off road yet). so far so good, bit yea insufficient testing still.

    at the free stroke fully turned in, what is the stroke of the lever before pads bite?

    front lever throw is at 17mm before firming.
    rear lever throw is at 22mm before firming.

    i think i still got a few pockets left for the rear... rear is a bit harder to bleed due to its position relative to the lever.
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  29. #29
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    I missed that part about extending the pistons and just burped mine with the lever at full reach and the stroke screw removed. Definitely more bubbles came out but it stil has the same squishy feel.

    By extending the pistons you mean squeezing the lever slightly while pads are removed and without the bleed block installed?

    I might as well try it, as I have to do a bleed again. I am getting a new syringe and maybe that will help with bleed. In any event, these brakes have been one huge disappointment.

  30. #30
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    well, can't compare with previous xt's since this is my first one. i came from a non series hydro with 160 rotor.

    in this setup, i got 180 fr/rr with resin finned pads. so far so good. has more tendency to OTB with incorrect positioning.

    ill switch to metallic once this resin is done.

    yep i extended mine without anything installed. thing is i may need to extend more for the rear... i cant confirm the bubbles though since the funnel is too far to be seen.

    anyone here knows up to which point can the pistons be extended without getting dislodged out of the caliper? worst case, if the piston pops out, is it just simply pushing back in?
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    Quote Originally Posted by spyghost View Post

    anyone here knows up to which point can the pistons be extended without getting dislodged out of the caliper? worst case, if the piston pops out, is it just simply pushing back in?
    I'd say keep it under 5mm per side, it's okay if they pop out but you will introduce air and you always risk damaging the seals when pressing them back in.

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    Canfield Yelli Screamy

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    Update for me with my M8000.

    I have f/r 180/160. The fronts have non finned resign pads. The rear have finned metal.

    I did a long climb, rested and started a DH. No braking in these wonderful S turns to start. So, the brakes were not hot at all.

    I then hit a new rain rut. I pulled the front tire up, and had a light feathery pull on the rear. The back wheel hit the rut hard and the lever for the rear brake got pumped up for a second. It then went back to normal.

    It seems the hard backend impact did something to make the lever firm up.

    Could this still be air trapped even though the brake was not hot at all?
    Lead by my Lefty............... right down the trail, no brakes.

  34. #34
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    M8000 brake "pumping up" on DH

    worth doing a full rebleed with the entire unit off the frame just like the vid so you can move the caliper around and tap it at any position, flick the hose, etc.

    imo, vids and instruction manuals are most of the time very ideal. more often i do each step more than what is prescribed.

    ive never experienced the pump issue so far.
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  35. #35
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    Quote Originally Posted by spyghost View Post
    worth doing a full rebleed with the entire unit off the frame just like the vid so you can move the caliper around and tap it at any position, flick the hose, etc.

    imo, vids and instruction manuals are most of the time very ideal. more often i do each step more than what is prescribed.

    ive never experienced the pump issue so far.
    I was thinking I would have to take it off the bike. The bad part for me is I have a lefty. I cannot figure how to get the lever between my head tube and lefty without taking the lefty off. That is a royal pain to do.

    I think I will go with my org plan now. I will reroute the hose away from the Lefty/headtube junction. I did that with the front for the same reason.
    Lead by my Lefty............... right down the trail, no brakes.

  36. #36
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    Quote Originally Posted by ziscwg View Post
    Update for me with my M8000.

    I have f/r 180/160. The fronts have non finned resign pads. The rear have finned metal.

    I did a long climb, rested and started a DH. No braking in these wonderful S turns to start. So, the brakes were not hot at all.

    I then hit a new rain rut. I pulled the front tire up, and had a light feathery pull on the rear. The back wheel hit the rut hard and the lever for the rear brake got pumped up for a second. It then went back to normal.

    It seems the hard backend impact did something to make the lever firm up.

    Could this still be air trapped even though the brake was not hot at all?
    Quote Originally Posted by spyghost View Post
    worth doing a full rebleed with the entire unit off the frame just like the vid so you can move the caliper around and tap it at any position, flick the hose, etc.

    imo, vids and instruction manuals are most of the time very ideal. more often i do each step more than what is prescribed.

    ive never experienced the pump issue so far.
    Quote Originally Posted by ziscwg View Post
    I was thinking I would have to take it off the bike. The bad part for me is I have a lefty. I cannot figure how to get the lever between my head tube and lefty without taking the lefty off. That is a royal pain to do.

    I think I will go with my org plan now. I will reroute the hose away from the Lefty/headtube junction. I did that with the front for the same reason.
    I finally got around to doing a full on bleed with the brake off the bike. I beat the piss out of the caliper while doing a few lever pulls. I did get a few bubbles from that.

    I also pushed the pistons all the back at the end. I did not leave them where the bleed block has them positioned.

    It finally stopped raining around here and I got a ride in on the course where the I experienced the pumping up on the DH. There was none

    However, the brakes seemed to squeal from heat where they did not before. (the pads were nowhere near the bleed process) Humm.

    Lastly, in ref other threads, I can pump the up with quick pulls on the work stand. Yet, they work normally as best I can tell at this time.

    I kinda wonder if I should have gone for the Saint brakes. I debated and I wonder if these problems are in Saints too?
    Lead by my Lefty............... right down the trail, no brakes.

  37. #37
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    Quote Originally Posted by ziscwg View Post
    I finally got around to doing a full on bleed with the brake off the bike. I beat the piss out of the caliper while doing a few lever pulls. I did get a few bubbles from that.

    I also pushed the pistons all the back at the end. I did not leave them where the bleed block has them positioned.

    It finally stopped raining around here and I got a ride in on the course where the I experienced the pumping up on the DH. There was none

    However, the brakes seemed to squeal from heat where they did not before. (the pads were nowhere near the bleed process) Humm.

    Lastly, in ref other threads, I can pump the up with quick pulls on the work stand. Yet, they work normally as best I can tell at this time.

    I kinda wonder if I should have gone for the Saint brakes. I debated and I wonder if these problems are in Saints too?
    My Saints pump up slightly but not near as much as the m8000's. The levers are similar but the size of the caliper is much larger. I found a new video on bleeding shimano brakes and will try the couple different things I noticed here.
    https://www.youtube.com/watch?v=3rvFfkYGkJ8

  38. #38
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    So my new XT's were doing this, and finally got tired of trying to solve it and sent them back to Shimano. I'm told they warrantied both and I have brand new ones on the way back to me. The rep I spoke with also told me they had made some changes to the master cylinder to resolve this issue, so take that FWIW.
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  39. #39
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    Quote Originally Posted by rscecil007 View Post
    So my new XT's were doing this, and finally got tired of trying to solve it and sent them back to Shimano. I'm told they warrantied both and I have brand new ones on the way back to me. The rep I spoke with also told me they had made some changes to the master cylinder to resolve this issue, so take that FWIW.
    I'd love to hear the outcome of this. I appear to have resolved the pumping up issue on the trail. However, I can pump them up a little in the stand. "a little" means I can change the min distance from the bar to the lever is 5 mm and pumped up is 10 mm. Not much really, but it shows you can still do it.
    Lead by my Lefty............... right down the trail, no brakes.

  40. #40
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    Once I get them mounted and some time on them I will report back.
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    I'm also about to return mine. Mine is a 9020
    The tech person told me, they're are going back to the white piston

  42. #42
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    My warranty replacements showed up today with white pistons, but my first set that was acting up had them as well.
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  43. #43
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    I might be missing something here. But the "pumping up" scenario on the 8000 series is precisely why I bought these over the older XT785 which were cheaper, fit my ispec shifters, bal, bla, bla. I use my brakes HARD, especially the front--and the 8000 series seems to "bleed" the brakes between the first and 2nd pump--giving more power and sensitivity on the 2nd stroke--seems there is some kind of additional venting that "bleeds" the system between strokes. Personally, I think the additional power is fantastic--gotta get used to it, but its all good. I use 203fr/180rr rotors if that helps

  44. #44
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    I've had this issue on one of my older M987 XTR Race brakes. I think I resolved it last night by modifying the pad return spring to exert less force for pad retraction.

    I pinched the 170 degree bend in the spring with a pliers down to 180 degrees. So far so good, with no rubbing, and no pumping up. I'll report back with how it is working, and if the pads have a greater tendency to rub on the rotor. For now the pad clearance seems unaffected.

    I was suspicious that the pumping up was a result of the pads returning quickly to normal position after releasing the brakes, then creeping further as a result of the spring pressure and requiring more lever throw on the first application.

    I also did a thorough bleed/fluid replacement prior to this, and although the fluid was very dirty and had taken on a gray hue, and lots of bubbles were removed, it did not resolve the issue.

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    Pumping takes away your ability to modulate the brakes.
    Not so bad when riding swoppy single tracks. But as soon as you point it down on a steeper sections, that pumping sucks

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    M8000 brake "pumping up" on DH

    Quote Originally Posted by Trackho View Post
    I might be missing something here. But the "pumping up" scenario on the 8000 series is precisely why I bought these over the older XT785 which were cheaper, fit my ispec shifters, bal, bla, bla. I use my brakes HARD, especially the front--and the 8000 series seems to "bleed" the brakes between the first and 2nd pump--giving more power and sensitivity on the 2nd stroke--seems there is some kind of additional venting that "bleeds" the system between strokes. Personally, I think the additional power is fantastic--gotta get used to it, but its all good. I use 203fr/180rr rotors if that helps
    i'm not fully convinced that is an additional feature. brakes ideally should have a consistent feel regardless of pad wear and terrain (point of bring hydraulic).

    getting used to it, yes riders can adapt to it, but still better for muscle memory to have something pulled consistently.
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    Quote Originally Posted by Trackho View Post
    I might be missing something here. But the "pumping up" scenario on the 8000 series is precisely why I bought these over the older XT785 which were cheaper, fit my ispec shifters, bal, bla, bla. I use my brakes HARD, especially the front--and the 8000 series seems to "bleed" the brakes between the first and 2nd pump--giving more power and sensitivity on the 2nd stroke--seems there is some kind of additional venting that "bleeds" the system between strokes. Personally, I think the additional power is fantastic--gotta get used to it, but its all good. I use 203fr/180rr rotors if that helps
    Quote Originally Posted by spyghost View Post
    i'm not fully convinced that is an additional feature. brakes ideally should have a consistent feel regardless of pad wear and terrain (point of bring hydraulic).

    getting used to it, yes riders can adapt to it, but still better for muscle memory to have something pulled consistently.
    I agree it's not a feature. If it was, you'd be able to replicate more easily. If that really was the intended design, then I never would have purchased the brakes.

    Also, Shimano would not be swapping them under warranty if that was a feature.

    Consistency is important. You pull the lever x distance, you get f in braking force. It should be that way all the time. Hot, cold, wet, dry all should be the same.

    Want more braking, pull further on handle

    If you like your M8000 for this pump up feature, have at it. I think you'll be in the minority.
    Lead by my Lefty............... right down the trail, no brakes.

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    Quote Originally Posted by ziscwg View Post
    I agree it's not a feature. If it was, you'd be able to replicate more easily. If that really was the intended design, then I never would have purchased the brakes.

    Also, Shimano would not be swapping them under warranty if that was a feature.

    Consistency is important. You pull the lever x distance, you get f in braking force. It should be that way all the time. Hot, cold, wet, dry all should be the same.

    Want more braking, pull further on handle

    If you like your M8000 for this pump up feature, have at it. I think you'll be in the minority.
    Too each their own--it is possible that I am misdiagnosing "the complaint". Having said that: Are you serious that you expect disk brakes to act the same way in the wet--it takes a few seconds to have the pads wipe the water off and heat up--maybe we use brakes differently, but I have to adjust my brake markers quite a bit earlier in the rain--like this am for example.

    Maybe I'm the first guy that used XT785s for multiple years and instantly appreciated the increased power on the 2nd stroke of the 8000s. To me brake feel is brake feel 1st pump or 2nd-wet dry, hot, cold-doesn't matter adjustments need to be made accordingly or "tomcatting" will ensue. The feel has to do with the brakes close to the limit--doesn't matter where the lever is--prolly just me though

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    Quote Originally Posted by brentos View Post
    I've had this issue on one of my older M987 XTR Race brakes. I think I resolved it last night by modifying the pad return spring to exert less force for pad retraction.

    I pinched the 170 degree bend in the spring with a pliers down to 180 degrees. So far so good, with no rubbing, and no pumping up. I'll report back with how it is working, and if the pads have a greater tendency to rub on the rotor. For now the pad clearance seems unaffected.

    I was suspicious that the pumping up was a result of the pads returning quickly to normal position after releasing the brakes, then creeping further as a result of the spring pressure and requiring more lever throw on the first application.

    I also did a thorough bleed/fluid replacement prior to this, and although the fluid was very dirty and had taken on a gray hue, and lots of bubbles were removed, it did not resolve the issue.
    Four rides and about 25 miles with the modified spring and the issue has not returned, so far, so good.

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    Hi brentos,
    How did you modify the return spring? Did you use a plier or some other technique?

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    Quote Originally Posted by Sobeco View Post
    Hi brentos,
    How did you modify the return spring? Did you use a plier or some other technique?
    Yes, I just pinched it at the bend with a pliers, I'll get a photo tonight...I over did it on the first try and had to open it back up again a bit. So don't go too far.

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    Ok, thanks for the info. A picture would be helpful, though.

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    Quote Originally Posted by brentos View Post
    I've had this issue on one of my older M987 XTR Race brakes. I think I resolved it last night by modifying the pad return spring to exert less force for pad retraction.

    I pinched the 170 degree bend in the spring with a pliers down to 180 degrees. So far so good, with no rubbing, and no pumping up. I'll report back with how it is working, and if the pads have a greater tendency to rub on the rotor. For now the pad clearance seems unaffected.

    I was suspicious that the pumping up was a result of the pads returning quickly to normal position after releasing the brakes, then creeping further as a result of the spring pressure and requiring more lever throw on the first application.

    I also did a thorough bleed/fluid replacement prior to this, and although the fluid was very dirty and had taken on a gray hue, and lots of bubbles were removed, it did not resolve the issue.
    Quote Originally Posted by brentos View Post
    Four rides and about 25 miles with the modified spring and the issue has not returned, so far, so good.
    Ya know,
    I have a hard time believing this is a fix because the springs really don't retract the pads, the seals do.

    HOWEVER, since what you did seems to work, I have my popcorn and I'm waiting to see how they fare after more rides.

    To really test, you should put a stock spring in the caliper and see if the problem returns.

    I will be the first to say I was wrong and give you rep if this is such a simple solution.
    Lead by my Lefty............... right down the trail, no brakes.

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    I didn't ride the bike over the weekend, but the first lever pull was spot on after sitting all weekend. I've got a 100 miler this weekend. We'll see...

    Before
    M8000 brake "pumping up" on DH-img_1894.jpg

    During
    M8000 brake "pumping up" on DH-img_1896.jpg

    After
    M8000 brake "pumping up" on DH-img_1897.jpg

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    Thanks for the photos and let us know whether the fix held after your 100 mi.

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    i can't imagine why/how this fix will work... interesting though...

    so, the top part of the spring should be parallel?
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    Quote Originally Posted by spyghost View Post
    i can't imagine why/how this fix will work... interesting though...

    so, the top part of the spring should be parallel?
    I can't either, but it's such a simple fix, you almost have try.
    Lead by my Lefty............... right down the trail, no brakes.

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    Quote Originally Posted by ziscwg View Post
    Ya know,
    I have a hard time believing this is a fix because the springs really don't retract the pads, the seals do.

    HOWEVER, since what you did seems to work, I have my popcorn and I'm waiting to see how they fare after more rides.

    To really test, you should put a stock spring in the caliper and see if the problem returns.

    I will be the first to say I was wrong and give you rep if this is such a simple solution.
    I used to think the seals did all of the retracting but after doing the same thing to my spring on my Zee brakes about 6 months ago, I can confirm that the spring most definitely contributes to pushing the pads/pistons back in.

    I don't know how this would work either unless it's the difference in covering up the port in the master cylinder vs not covering it up with less slave piston retraction.

    For what it's worth, I was having a different issue and I went back to a stock spring because it made my pads noisy (clatter) from a lack of tension over bumps or on the first application of the brakes.
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    Quote Originally Posted by Sobeco View Post
    Thanks for the photos and let us know whether the fix held after your 100 mi.
    After about 150 miles on pretty rough terrain, the fix is still effective, with no noticeable issues.

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    Thanks for getting back to us. Good to hear that the fix is still working!

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    Quote Originally Posted by Sobeco View Post
    Thanks for getting back to us. Good to hear that the fix is still working!
    just curious, have you compared this spring if it has changed from the previous models?

    afaik, the pads changed from F03C to J03C as far as metallic finned pads are concerned. not sure about the other types of pads for XT if they have changed or if the spring itself has changed.

    this also makes me wonder what the brake response will be if the previous model pad kits are used...
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    So, after lubing the pistons/seals with finish line suspension spray and doing a full bleed of the rear brakes a few months back I made it out Bailey MTB park and just realized I didn't have any pump up or inconsistent lever pull the whole weekend. Though the brakes still don't self adjust for wear as well as I think they should.

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    I had one pump up yesterday. It was on a medium style downhill with turns you have to slow for significantly.

    I had a fairly hard back end hit with light pressure on the rear brake lever. They lever moved out, but allowed the same braking I was applying. Kind of odd, but barely noticeable really. I take note of any change in lever throw right now .

    I may have to try the spring thing mentioned above.
    Lead by my Lefty............... right down the trail, no brakes.

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    Waking this one up. Any changes? Any confirmed fixes? Mine have been doing the pump up thing since day 1 and I've been "dealing with it" for a couple months, now. I have bled them numerous different ways in an effort to find a magic combination, to no avail. I didn't try an off the bike bleed because if I have to do that, I'll throw these P'sOS in the garbage. Quite simply, levers should not pump up and they shouldn't need to be removed for a proper bleed. I have a new set of 785's enroute to replace these before that supply dries up. Any warranty claimers have success with your replacements or just continued pump up?

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    Quote Originally Posted by Oh My Sack! View Post
    Waking this one up. Any changes? Any confirmed fixes? Mine have been doing the pump up thing since day 1 and I've been "dealing with it" for a couple months, now. I have bled them numerous different ways in an effort to find a magic combination, to no avail. I didn't try an off the bike bleed because if I have to do that, I'll throw these P'sOS in the garbage. Quite simply, levers should not pump up and they shouldn't need to be removed for a proper bleed. I have a new set of 785's enroute to replace these before that supply dries up. Any warranty claimers have success with your replacements or just continued pump up?
    I'm in exactly same boat. Want to warranty but prefer a fix as don't want to be off bike for a couple weeks while Shimano Aus farts around.

    Pumping up less but still happening since i tried the pliers and squeezed the brake clips but that's a BS fix.



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    The next time you guys get the pump, would it be possible to crack open the fill hole and tighten it back up and see if it goes away? If that doesn't work, loosen both bolts a bit and tighten them back up and try again.
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    Quote Originally Posted by BuickGN View Post
    The next time you guys get the pump, would it be possible to crack open the fill hole and tighten it back up and see if it goes away? If that doesn't work, loosen both bolts a bit and tighten them back up and try again.
    As has been discussed, the pump is intermittent and goes away as fast as it comes on. It NEVER stays firm at the top of stroke. As soon as you let off for just a fraction of time, it's gone. Breaking the bleed screw seal and introducing air into the master doesn't seem like a good idea while out on a ride so I'm not sure what benefit that would achieve.

    By "loosen bolts a bit...and tighten", which bolts are you referring...the caliper mount bolts?

    My rear lever "seemed" to have settled down a bit over the last few rides but I was on a fast downhill on Saturday and all of a sudden my front pumped up quite severely and that hadn't happened to that degree in the past. This would have been a catastrophic place to have a get-off. I doubt I'd be walking out, surely not riding out after a fall on that section. I have a good friend/daily riding buddy that has an inside connection with Shimano. We discussed it today and he's going to him to see what can be done, if anything. I'm not about to play patty-cake with them and shipping warranty crap back and forth if there's no fix on the return item. I'm pulling these off as soon as my 785's land here and then I'll go to battle with Shimano if I have to.

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    Quote Originally Posted by BuickGN View Post
    The next time you guys get the pump, would it be possible to crack open the fill hole and tighten it back up and see if it goes away? If that doesn't work, loosen both bolts a bit and tighten them back up and try again.
    Yeah. I push the pistons all the way in and crack the lever bleed screw to ensure there isn't excess fluid in the brake. If you bleed the brakes without pushing the pistons all the way in there can be too much, which can lead to pump and lockup if it heats up. If for some reason you do get a small amount of air in the reservoir, it won't cause any problems...and might contribute to solving pump-up if it allows a little more room for fluid expansion. I wouldn't recommend intentionally putting air in the reservoir though.

    Unrelated, but Shimano brakes pump up in cold weather (around freezing) due to the viscosity of the fluid.

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    Quote Originally Posted by Lone Rager View Post
    Yeah. I push the pistons all the way in and crack the lever bleed screw to ensure there isn't excess fluid in the brake. If you bleed the brakes without pushing the pistons all the way in there can be too much, which can lead to pump and lockup if it heats up. If for some reason you do get a small amount of air in the reservoir, it won't cause any problems...and might contribute to solving pump-up if it allows a little more room for fluid expansion. I wouldn't recommend intentionally putting air in the reservoir though.

    Unrelated, but Shimano brakes pump up in cold weather (around freezing) due to the viscosity of the fluid.
    That's exactly what I was wondering. I was also thinking what if fluid got above the diaphragm somehow or are these the new design that don't use a diaphragm?
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    I picked up a set of these for my new Ibis build and had the same issue front and rear. I tried a re-bleed and the problem continued. The Shimano warehouse is about 15 mins from my house so I just dropped them off yesterday for a warranty replacement. Hopefuly the replacements will be better or it's back to the M785's for me as well. I'll post back when I have the replacements and can get a couple of rides on them. It's a real bummer as I've been an XT brake fan for quite a while.

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    Quote Originally Posted by guitarjohn21 View Post
    I recently had the new 2016 shimano m8000's installed and I am having some issues when going through rough sections of trail. With fingers on the levers, I can feel them pump up when I go thru fast rough sections and DH sections. The bite point changes drastically and yesterday had a minor crash because of it. I think they locked up on me when I had them feathered and pointed the bike down a vertical drop. I haven't done any work on these yet, I normally install & bleed my own brakes but I had a shop install these because I was too busy that week. Nothing like this ever on the m785's which I still have on 2 other bikes.
    Anyone else have similar experience?
    just bought a genius 910 and it came with these. i loved my old XTs and i am experiencing the same thing. to a point to where its scary. Im bout ready to toss them in the trash..
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    Quote Originally Posted by mikodipo View Post
    The pumping up that I experienced was the engagement point moving out and I would have to let go of the brake and reapply for it to be back to the normal engagement point. Not so much where it would brake without pulling the lever, but a lot sooner than it normally would. This typically happened when going down critical parts of the trail where I would be rapidly braking on and off.
    mine are doing exact same thing. whats the fix??
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    Quote Originally Posted by F29Lefty View Post
    mine are doing exact same thing. whats the fix??
    My fix was getting SRAM guides... Again this was happening on my 785s which people never seem to have issues with, but I also experienced it with the SLX equivalent.

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    I've run NUMEROUS sets of 785's. Never seen the issue there nor has anyone else that I know that has them....and that's a lot of riders. Apparently the XTR's had this issue, so I have heard. That's pretty much the master we're dealing with, now on the M8000.

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    Quote Originally Posted by mikodipo View Post
    My fix was getting SRAM guides... Again this was happening on my 785s which people never seem to have issues with, but I also experienced it with the SLX equivalent.
    i was afraid of that. which ones the ultimates? i just dropped a shit load of money on this bike. not ready for a 500$ brake upgrade? my m785s were money never had this issue but just get those. f*** I'm so mad
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    Quote Originally Posted by F29Lefty View Post
    i was afraid of that. which ones the ultimates? i just dropped a shit load of money on this bike. not ready for a 500$ brake upgrade? my m785s were money never had this issue but just get those. f*** I'm so mad
    I have the RSCs. The ultimates weren't out yet when I bought mine. If you liked the 785s, why not get them? They're still available and are only around $80 a brake.

    Have you tried shimano's warranty? They're super easy to deal with. I wonder if they have any old 785s they would be willing to give you instead.

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    Quote Originally Posted by mikodipo View Post
    I have the RSCs. The ultimates weren't out yet when I bought mine. If you liked the 785s, why not get them? They're still available and are only around $80 a brake.

    Have you tried shimano's warranty? They're super easy to deal with. I wonder if they have any old 785s they would be willing to give you instead.
    yah i wish i kept my old m785s. i just had them put brand new ice techs on too. might just do that. i hear such good things bout guides now. i want them. but thats new rotors and brakes. ughhh this sport is so expensive lol
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    Quote Originally Posted by F29Lefty View Post
    yah i wish i kept my old m785s. i just had them put brand new ice techs on too. might just do that. i hear such good things bout guides now. i want them. but thats new rotors and brakes. ughhh this sport is so expensive lol
    You don't need new rotors. I run ice tech with my guides

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    Quote Originally Posted by mikodipo View Post
    You don't need new rotors. I run ice tech with my guides
    oh really?? they work good? are the RSCs good or just go ultimate?
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    You can buy a f/r set of 785's for $137. A set of 8000's for $154. After years of Avid's bullsh*t. I'd keep sh*tty functioning 8000's on my bike before I went back to a SRAM brake. If you want to dump extra money, buy Saint 4 piston f/r set for $250.

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    Take your pick. Bullsh*t or sh*tty. I went with bullsh*t. I agree though, avids taperbore was crap.

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    Quote Originally Posted by F29Lefty View Post
    oh really?? they work good? are the RSCs good or just go ultimate?
    I don't have experience with ultimates so I can't comment. I did however have some chatter with the ice tech rotors but I blame it on 2 year old rotors with the new set of brakes that have a different surface area than the shimano's. I have a set of centerlines waiting to be installed if the chatter bothered me enough but it just went away.

    As for recommending one brake over another, I do like the modulation of the guides over the 785s. Shimano's are definitely easier to set up where I have to mess around with the caliper a bit to get things lined up without rubbing. This also may be because my rotors are slightly not aligned since they're kinda old now and that shimano is servowave to keep the pads far away from the rotors when the brake lever isn't engaged.

    I also do all my maintenance so I have the luxury and patience to bleed my brakes. SRAM brakes do take longer to bleed but I have more control over the bleed than the shimano's.

    There was one time I got my 785s running relatively fine when I completely drained the system and refilled the system. I've even put my orbital sander on the brake line (no sand paper but just to get it to vibrate) while bleeding to get all the bubbles out. I've even paid a shop to bleed my brakes thinking it was my bleeds that were bad, but they still pumped up. That's when I had enough with those brakes. Also, I went through 3 xt derailleurs because they kept getting bent (not my hanger either, I have an alignment tool to check). Now I'm on sram drivetrain.

    Long story short, I was convinced through forums that shimano's were the best, but in my experience, they didn't fit the bill.

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    Quote Originally Posted by mikodipo View Post
    I don't have experience with ultimates so I can't comment. I did however have some chatter with the ice tech rotors but I blame it on 2 year old rotors with the new set of brakes that have a different surface area than the shimano's. I have a set of centerlines waiting to be installed if the chatter bothered me enough but it just went away.

    As for recommending one brake over another, I do like the modulation of the guides over the 785s. Shimano's are definitely easier to set up where I have to mess around with the caliper a bit to get things lined up without rubbing. This also may be because my rotors are slightly not aligned since they're kinda old now and that shimano is servowave to keep the pads far away from the rotors when the brake lever isn't engaged.

    I also do all my maintenance so I have the luxury and patience to bleed my brakes. SRAM brakes do take longer to bleed but I have more control over the bleed than the shimano's.

    There was one time I got my 785s running relatively fine when I completely drained the system and refilled the system. I've even put my orbital sander on the brake line (no sand paper but just to get it to vibrate) while bleeding to get all the bubbles out. I've even paid a shop to bleed my brakes thinking it was my bleeds that were bad, but they still pumped up. That's when I had enough with those brakes. Also, I went through 3 xt derailleurs because they kept getting bent (not my hanger either, I have an alignment tool to check). Now I'm on sram drivetrain.

    Long story short, I was convinced through forums that shimano's were the best, but in my experience, they didn't fit the bill.
    all the guide reviews seem really positive. can't find much good on the m8000s... I'm definitely getting the guides just not sure RSC vs ultimate... my wallet says RSC and my heart says ultimate haha
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    My warranty replacements showed up yesterday. Not bad since I just dropped them off at Shimano on Monday. Mounted them up this morning and will take them for a spin this afternoon. I've got my fingers crossed that these will be better........

  85. #85
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    Quote Originally Posted by socaltrailrider View Post
    My warranty replacements showed up yesterday. Not bad since I just dropped them off at Shimano on Monday. Mounted them up this morning and will take them for a spin this afternoon. I've got my fingers crossed that these will be better........
    Report back... I'm curious to see. Bout to pull trigger on guides
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    Just got off the phone with Shinamo. After one talking to one guy who was clueless.. Not sure the even knows where he works.. Lol finally got to someone who knew what was up. The brakes have a 4 letter code on a silver sticker and if the bottom 2 letters are "NG" they are supposed to be the "good version" of these brakes. So I checked mine. My front says "NG" and rear says "ND" which falls under the "bad ones". But both my brakes are having the same issue. So they said they will replace them. But I think I'm just going to buy guides.
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    Get the replacement then sell them to help pay for your new brakes

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    Quote Originally Posted by F29Lefty View Post
    Just got off the phone with Shinamo. After one talking to one guy who was clueless.. Not sure the even knows where he works.. Lol finally got to someone who knew what was up. The brakes have a 4 letter code on a silver sticker and if the bottom 2 letters are "NG" they are supposed to be the "good version" of these brakes. So I checked mine. My front says "NG" and rear says "ND" which falls under the "bad ones". But both my brakes are having the same issue. So they said they will replace them. But I think I'm just going to buy guides.
    That's moving forward. Thanks for posting that tidbit. Both f/r of mine are "NE". I'm riding mine for the rest of the week and then my new 785's will be here. I'll call Shimano after I make the change and get replacements and see where that goes.

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    Quote Originally Posted by F29Lefty View Post
    Report back... I'm curious to see. Bout to pull trigger on guides
    The Zees are also very nice and they're not redesigned as the 2 piston line is so reliability should still be excellent. Just throwing out another option if you like Shimano brakes in general.
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  90. #90
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    So took my bike in. Shimano is doing a full warrantied replacement. My LBS is crediting me full retail for the M8000s and they ordered my a set of Guide RSC's with centerline rotors and I just have to pay the difference. So I have a brand new set of 180mm ice techs if anyone wants them. Shoot me an offer.
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  91. #91
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    Quote Originally Posted by F29Lefty View Post
    Report back... I'm curious to see. Bout to pull trigger on guides
    Just got back from my ride. Three technical descents on this one. Brakes worked perfectly. No pumping up and good modulation. I ran them with the factory bleed.

  92. #92
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    Quote Originally Posted by socaltrailrider View Post
    Just got back from my ride. Three technical descents on this one. Brakes worked perfectly. No pumping up and good modulation. I ran them with the factory bleed.
    rs, rsc, or ultimate?
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  93. #93
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    Quote Originally Posted by socaltrailrider View Post
    Just got back from my ride. Three technical descents on this one. Brakes worked perfectly. No pumping up and good modulation. I ran them with the factory bleed.
    I had them re-bleed mine today while i wait for the Guide's i had them order.. the problem is worst then before. Its so bad the bike is un-ridable. Looks like ill be on my road bike for the next couple days.
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  94. #94
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    Quote Originally Posted by Oh My Sack! View Post
    Waking this one up. Any changes? Any confirmed fixes? Mine have been doing the pump up thing since day 1 and I've been "dealing with it" for a couple months, now. I have bled them numerous different ways in an effort to find a magic combination, to no avail. I didn't try an off the bike bleed because if I have to do that, I'll throw these P'sOS in the garbage. Quite simply, levers should not pump up and they shouldn't need to be removed for a proper bleed. I have a new set of 785's enroute to replace these before that supply dries up. Any warranty claimers have success with your replacements or just continued pump up?
    300 miles later, the spring adjustment is working flawlessly for me still. This is on the XTR M987 that I was experiencing the same issue with, so it may not apply to the M8000's. Anyone else tried this yet on a pair of M8000's?

  95. #95
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    Quote Originally Posted by F29Lefty View Post
    Just got off the phone with Shinamo. After one talking to one guy who was clueless.. Not sure the even knows where he works.. Lol finally got to someone who knew what was up. The brakes have a 4 letter code on a silver sticker and if the bottom 2 letters are "NG" they are supposed to be the "good version" of these brakes. So I checked mine. My front says "NG" and rear says "ND" which falls under the "bad ones". But both my brakes are having the same issue. So they said they will replace them. But I think I'm just going to buy guides.
    Where is this sticker located? I just looked all over mine and see no sticker. Thanks.
    NTFTC

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    Quote Originally Posted by F29Lefty View Post
    Just got off the phone with Shinamo. After one talking to one guy who was clueless.. Not sure the even knows where he works.. Lol finally got to someone who knew what was up. The brakes have a 4 letter code on a silver sticker and if the bottom 2 letters are "NG" they are supposed to be the "good version" of these brakes. So I checked mine. My front says "NG" and rear says "ND" which falls under the "bad ones". But both my brakes are having the same issue. So they said they will replace them. But I think I'm just going to buy guides.
    Mine are both NG and I've got pumping up in both.....

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  97. #97
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    Quote Originally Posted by spyghost View Post
    rs, rsc, or ultimate?
    Warranty replacement M8000's.

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    Geez. In the beginning I thought there were just a couple of isolated toothing problems with the new brakes. It's becoming an epidemic around here. I know this board attracts people with problems and I'm sure in the real world most are satisfied but this seems like an especially high percentage of problems, the same problems, especially for Shimano. If it continues and gets worse I hope they do the right thing.
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    Quote Originally Posted by thegweed View Post
    Where is this sticker located? I just looked all over mine and see no sticker. Thanks.
    On the bottom side of the lever body. It's a small silver circular sticker right next to the lever pivot. Looking at mine, it looked like a pivot pin mounted flush. The letters are tiny. I used a mirror and flashlight to see mine without loosening and twisting the lever upwards.

  100. #100
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    Quote Originally Posted by BuickGN View Post
    Geez. In the beginning I thought there were just a couple of isolated toothing problems with the new brakes. It's becoming an epidemic around here. I know this board attracts people with problems and I'm sure in the real world most are satisfied but this seems like an especially high percentage of problems, the same problems, especially for Shimano. If it continues and gets worse I hope they do the right thing.
    I agree 100%. I talked to 3 people on the phone from Shimano and didn't seem like any of them really cared. I said "you guys realized there is a forum out with tons of people un happy with your products and they are un safe?" Dude didn't really care. So I said that's fine I'm buying SRAM.
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  101. #101
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    Quote Originally Posted by northvanguy View Post
    Mine are both NG and I've got pumping up in both.....

    Sent from my SM-G361F using Tapatalk
    One of mine is NG and that's supposed to be the "good one" had it re bleed. The problem got worse.
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  102. #102
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    M8000 brake "pumping up" on DH-image.jpg
    Quote Originally Posted by thegweed View Post
    Where is this sticker located? I just looked all over mine and see no sticker. Thanks.
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  103. #103
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    My replacement set that work well are NI. I wonder if the lettering is sequential and the "I" is a newer manufacturing batch than the "G".

  104. #104
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    Quote Originally Posted by socaltrailrider View Post
    My replacement set that work well are NI. I wonder if the lettering is sequential and the "I" is a newer manufacturing batch than the "G".
    anything is possible.

  105. #105
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    Thanks. NC rear and ND front, no problems whatsoever...but there's no downhill here in Florida. No problems at the Kerr Scott trails either.
    NTFTC

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    M8000 brake "pumping up" on DH-image.jpg

    Problem solved.
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  107. #107
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    M8000 brake "pumping up" on DH

    Quote Originally Posted by F29Lefty View Post
    Click image for larger version. 

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    Problem solved.
    let us know how it goes or what nasties come with a guide rsc.

    am already leaning towards getting a set for me. only hesitation is that it does not accept ispec ii. no problem solvers yet
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  108. #108
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    Quote Originally Posted by spyghost View Post
    let us know how it goes or what nasties come with a guide rsc.

    am already leaning towards getting a set for me. only hesitation is that it does not accept ispec ii. no problem solvers yet
    Yah I ended up buying a full X01 drivetrain as well cause the brakes mount to my reverb dropper and to the SRAM shifter.... Here I am $1,000 later... Lol
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    I understand... I went xo1 too and they are better integrated than the ispecs since you can actually rotate the shifters.

  110. #110
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    Okay you Avid fanboys...good luck with that but beat it, now. We're here to piss and moan about 8000's.

  111. #111
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    Quote Originally Posted by F29Lefty View Post

    Problem solved.
    fantastic

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    My fear is sending them to warranty and Shimano telling me they're fine...

    Live in Aus and bought off CRC presuming it's Shimano XT so no way I'd have a problem....

    Sent from my SM-G361F using Tapatalk

  113. #113
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    Quote Originally Posted by F29Lefty View Post
    Just got off the phone with Shinamo. After one talking to one guy who was clueless.. Not sure the even knows where he works.. Lol finally got to someone who knew what was up. The brakes have a 4 letter code on a silver sticker and if the bottom 2 letters are "NG" they are supposed to be the "good version" of these brakes. So I checked mine. My front says "NG" and rear says "ND" which falls under the "bad ones". But both my brakes are having the same issue. So they said they will replace them. But I think I'm just going to buy guides.
    Hummm
    My slightly troublesome one is NC
    My good one is NG

    the other thing is my troublesome one NC is the one I cut the hose on. My good one is the NG and has stock hose length
    Lead by my Lefty............... right down the trail, no brakes.

  114. #114
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    reporting back.. first ride on the guide RSCs... wow. blown away. unbelievable control. its almost like having traction control. there was times i was sure the rear was gunna lock up or the front would slide in sections i was going pretty fast in corners and really got on the brakes hard. maintained traction the entire time. I'm sold. money well spend. I'm a fan now.. props to sram
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  115. #115
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    Quote Originally Posted by F29Lefty View Post
    reporting back.. first ride on the guide RSCs... wow. blown away. unbelievable control. its almost like having traction control. there was times i was sure the rear was gunna lock up or the front would slide in sections i was going pretty fast in corners and really got on the brakes hard. maintained traction the entire time. I'm sold. money well spend. I'm a fan now.. props to sram
    Felt the same. Was able to maintain traction without sliding in steep rock gardens.

  116. #116
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    This thread has definitely taken a turn, but back to the original point... I upgraded my old school XTs to Saint calipers paired with M9000 levers and have the exact same provlem as described.

    I've spent so much money on this setup that I would like to believe that it's just bled poorly, but I'm considering a set of Formula brakes.

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    I had lots of issues with formula. I suggest you to fix the issue with your current setup. Check YouTube video on GMBN channel. They have a nice video how to bleed Shimano brakes.

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  118. #118
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    Quote Originally Posted by ziscwg View Post
    Hummm
    My slightly troublesome one is NC
    My good one is NG

    the other thing is my troublesome one NC is the one I cut the hose on. My good one is the NG and has stock hose length
    mine are NG and both pump, the rear being worse

    (still Not Good)
    Last edited by spyghost; 04-10-2016 at 08:00 PM.
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  119. #119
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    Quote Originally Posted by kjmccarx View Post
    This thread has definitely taken a turn, but back to the original point... I upgraded my old school XTs to Saint calipers paired with M9000 levers and have the exact same provlem as described.

    I've spent so much money on this setup that I would like to believe that it's just bled poorly, but I'm considering a set of Formula brakes.
    Yahhh sorry bout that. Haha. I just get so frustrated... You spend 5k on a brand new bike and you have to replace the brakes right away. Just doesn't make since. But couldn't be more "pumped" (no pun intended lol) on my new guides. Rant over.
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    Does anyone who's had their m8000's warrantied have anything in writing from shimano that they can post up?

    Ridiculous that when i call Shimano they seem 100% oblivious to this problem.

    Ideally would like to send along details that Shimano elsewhere in world has provided along with my brakes to help with expediting the process.

    Sent from my SM-G361F using Tapatalk

  121. #121
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    Quote Originally Posted by northvanguy View Post
    Does anyone who's had their m8000's warrantied have anything in writing from shimano that they can post up?

    Ridiculous that when i call Shimano they seem 100% oblivious to this problem.

    Ideally would like to send along details that Shimano elsewhere in world has provided along with my brakes to help with expediting the process.

    Sent from my SM-G361F using Tapatalk
    When I called they seemed like they had no clue there is a problem. Just clueless.
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  122. #122
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    Quote Originally Posted by F29Lefty View Post
    When I called they seemed like they had no clue there is a problem. Just clueless.
    Identical to my call to Shimano... that's why if ppl could share any written reply they've got from Shimano we can all lean on it to hopefully help us speed up our warranty claims

  123. #123
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    Quote Originally Posted by northvanguy View Post
    Identical to my call to Shimano... that's why if ppl could share any written reply they've got from Shimano we can all lean on it to hopefully help us speed up our warranty claims
    I just let the dealer handle it. But I'll see what I can find out.
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  124. #124
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    When I sent mine in for the same issue, I was sent a replacement set within a week to California, even though the person on the phone was clueless.

    I think they just send a new one without examining the returned pair as that's probably the easier solution.

  125. #125
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    Quote Originally Posted by mikodipo View Post
    When I sent mine in for the same issue, I was sent a replacement set within a week to California, even though the person on the phone was clueless.

    I think they just send a new one without examining the returned pair as that's probably the easier solution.
    Does your new set pump up?
    It is no measure of health to be well adjusted to a profoundly sick society.

  126. #126
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    Quote Originally Posted by WHALENARD View Post
    Does your new set pump up?
    Yes they did.

  127. #127
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    Quote Originally Posted by mikodipo View Post
    Yes they did.
    "Did"? Past tense. What was resolution?

    Another warranty or did you give up and try something else?

  128. #128
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    Quote Originally Posted by northvanguy View Post
    "Did"? Past tense. What was resolution?

    Another warranty or did you give up and try something else?
    I got SRAM guides to replace the XTs. Problem solved.

  129. #129
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    Quote Originally Posted by mikodipo View Post
    I got SRAM guides to replace the XTs. Problem solved.
    That wasn't the reply i was hoping for

  130. #130
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    Shimano just announced Di2 version of m8000. I hope this release fixes this brake pump issue
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  131. #131
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    Quote Originally Posted by mikodipo View Post
    I got SRAM guides to replace the XTs. Problem solved.
    Haha, to resolve Avid issues in the past, Shimano was the answer, now it's the other way around

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    Magazines are picking up the issues now:


  133. #133
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    Quote Originally Posted by ziscwg View Post
    I can't either, but it's such a simple fix, you almost have try.
    Quote Originally Posted by Sobeco View Post
    Thanks for the photos and let us know whether the fix held after your 100 mi.
    Quote Originally Posted by brentos View Post
    After about 150 miles on pretty rough terrain, the fix is still effective, with no noticeable issues.
    this workaround seemed to work well. i haven't had much distance on this fix yet, but in my weekend ride yesterday on rough terrain, i can't feel any pump. the lever throw remained consistent from the time i went out 'till i got home.

    this still need further (long term) testing though. also, as an observation, the top part of the of spring should be parallel to each other when setting. if it weren't parallel, then the brake pump will be experienced, but less. it seems though that as the top part becomes more parallel, the brake pump diminishes to the point that it goes away.

    could it be that:
    1 - shimano changed the springs to something 'tougher'? hence fluid is forced back to the MC after the first release 'immediately', and/or
    2 - the MC has a return circuit that cannot compensate well for this rapid return of fluid

    in both or either scenarios, fluid remains under pressure beyond the MC hence increasing the bite point on successive brakes when done at a specific time interval.

    these are just assumptions given the 'workaround' of pinching the spring.
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  134. #134
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    Quote Originally Posted by Rick Draper View Post
    Magazines are picking up the issues now:

    Leaves one wanting more. What lever, where do we get one, and do new versions have said lever?
    It is no measure of health to be well adjusted to a profoundly sick society.

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    Quote Originally Posted by WHALENARD View Post
    Leaves one wanting more. What lever, where do we get one, and do new versions have said lever?
    Yep. Would be nice to see some clarity from Shimano. Won't happen though....

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    Interesting. My M8000s that went onto a 429SL have been doing this. I just thought it was a shoddy bleed and, as the bike doesn't get too much serious steep action (the HD3 is for that), didn't really think much about it. Was and is bloody annoying when the bike does get into fun terrain, but now I'll put a bit more focus on it!

    For note, my 2 other sets of M785s are perfect and have been for years I also have had no dramas at all with my Avid Codes of a couple of different generations on DH bikes.

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    Maybe some good news, just got a set with codes NJ and OA. No pump up issues out of the box with factory bleed and nice firm lever. Rode 2 bikes the past week with new XT's and they were flawless as well (I forgot to look at codes). Hopefully Shimano got it figured out. Almost went with Guides but figured I'd take a chance after riding those bikes and feeling how good XT's can be if they don't pump up. We'll see.

  138. #138
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    Quote Originally Posted by gasmanxj View Post
    Maybe some good news, just got a set with codes NJ and OA. No pump up issues out of the box with factory bleed and nice firm lever. Rode 2 bikes the past week with new XT's and they were flawless as well (I forgot to look at codes). Hopefully Shimano got it figured out. Almost went with Guides but figured I'd take a chance after riding those bikes and feeling how good XT's can be if they don't pump up. We'll see.
    have you cut the hoses from new ones?
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    Quote Originally Posted by spyghost View Post
    have you cut the hoses from new ones?
    Not yet. Will see what happens when I do and report back when I get some good rides in.

  140. #140
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    Quote Originally Posted by gasmanxj View Post
    Maybe some good news, just got a set with codes NJ and OA. No pump up issues out of the box with factory bleed and nice firm lever. Rode 2 bikes the past week with new XT's and they were flawless as well (I forgot to look at codes). Hopefully Shimano got it figured out. Almost went with Guides but figured I'd take a chance after riding those bikes and feeling how good XT's can be if they don't pump up. We'll see.
    Quote Originally Posted by spyghost View Post
    have you cut the hoses from new ones?
    Quote Originally Posted by gasmanxj View Post
    Not yet. Will see what happens when I do and report back when I get some good rides in.
    Have you ridden some nar stuff where your back wheel is taking a beating? Like a lot of hits in rapid succession. That is the only way I can test. My issue is minor, but still happens when I do that rear wheel torture test
    Lead by my Lefty............... right down the trail, no brakes.

  141. #141
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    Quote Originally Posted by ziscwg View Post
    Have you ridden some nar stuff where your back wheel is taking a beating? Like a lot of hits in rapid succession. That is the only way I can test. My issue is minor, but still happens when I do that rear wheel torture test
    to add it doesn't just occur in the rear, front as well.

    successive quick pull/release even on dh pavement reveals this issue. gnar stuff highlights it more quickly though.
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  142. #142
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    Quote Originally Posted by spyghost View Post
    successive quick pull/release even on dh pavement reveals this issue. gnar stuff highlights it more quickly though.
    Yep, have 8000's on my current bike and they pump up on pavement when doing quick pull/release. The new 8000's are for a new build so I just tossed them on the old bike real quick and took a spin around the neighborhood, zero sign of pump up. Agree with ziscwg the real test will be hitting some chunk but at least it's promising so far. Rode a demo 6Fattle last week on a 10 mile burn through chunk and the 8000's were perfect so that gave me some hope to try a new set.

  143. #143
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    I picked up my new Top Fuel 9.8 yesterday. It has Shimano 8000 brakes. I was concerned after reading everything about the brakes "pumping up". My first ride was this morning and I made sure to go down rough, rocky trails to see if the brakes would pump up. I did get it to occur, but only when I apply the rear brake in very rapid succession. Only then, did it occur, but quickly went away when I stopped flicking the brake. I don't normally brake in that manner so it didn't occur again on my ride. It was just a test. I don't think this will be an issue for me.

    The brakes have white pistons and mfg code OA.

  144. #144
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    Quote Originally Posted by gasmanxj View Post
    Maybe some good news, just got a set with codes NJ and OA. No pump up issues out of the box with factory bleed and nice firm lever. Rode 2 bikes the past week with new XT's and they were flawless as well (I forgot to look at codes). Hopefully Shimano got it figured out. Almost went with Guides but figured I'd take a chance after riding those bikes and feeling how good XT's can be if they don't pump up. We'll see.
    Gasmanxj, have you been able to get more time on the new 8000s? If so, any news good or bad?
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  145. #145
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    Quote Originally Posted by danny.mendes View Post
    Gasmanxj, have you been able to get more time on the new 8000s? If so, any news good or bad?
    Not yet, still waiting on new frame to hang them on.

  146. #146
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    I'm scared to say anything but I have a set of these on my wifes endorphin and I have a set on my ns eccentric. Both sets were sourced from germany.

    I got them because I was building a new bike, she got them because we had the pumping issue on one of her SLX brakes.

    So far, no such pumping issues with either set. Both sets required shortening of the hoses that introduced air to the systems. I was able to perform a full bleed that returned them to functioning normally after this.

    When I bled, I made sure to adjust the reach adjust to full extension and I kept the pads in the caliper mounted to the disc. This seemed to make a difference on the air I was able to get out of there...as such they may be slightly overfilled?

  147. #147
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    I had xtr 9020 with the pumping issue.
    I bought some XT M8000 last month (from France), J-Kit version, and i'm happy to report that they are without issue, like old xt and xtr from the previous generation.
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  148. #148
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    Quote Originally Posted by 20.100 FR View Post
    I had xtr 9020 with the pumping issue.
    I bought some XT M8000 last month (from France), J-Kit version, and i'm happy to report that they are without issue, like old xt and xtr from the previous generation.
    What do you mean by "J-Kit version"? Do you mean "J" date code?
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  149. #149
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    Never mind, I looked up what Shimano J-Kit is.
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  150. #150
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    I'd like to report that after trying to cycle my brake piston several times and tapping the caliper, brake hose and lever using rubber mallet during the process now the brake feels more firm and no longer felt the "pumping"

    Looks like there may be a trapped air inside the caliper or lever that finally break loose when I try to cycle the brake pistons.

  151. #151
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    Quote Originally Posted by gutzz View Post
    I'd like to report that after trying to cycle my brake piston several times and tapping the caliper, brake hose and lever using rubber mallet during the process now the brake feels more firm and no longer felt the "pumping"

    Looks like there may be a trapped air inside the caliper or lever that finally break loose when I try to cycle the brake pistons.
    by cycle the pistons, what do you mean?
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  152. #152
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    Quote Originally Posted by spyghost View Post
    by cycle the pistons, what do you mean?
    Forgot to explain

    Here is how I did it:
    - remove the wheels and brakepads
    - clean the caliper and pistons
    - pull the brake lever several times while watching the pistons move (be CAREFUL and don't let it move too far)
    - tap the caliper, hose and lever using something like rubber mallet or plastic screwdriver
    - spread the pistons using plastic tire lever
    - tap everything once more
    - repeat

    As the final step you can try to pull the lever with bleeding blocks on the caliper to see how the lever feels now.

  153. #153
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    M8000 brake "pumping up" on DH-image.jpgI opened package of 2 new 8000 brakes. Hung from lever, so the brake lines were perpendicular to planet Earth, tapped caliper and hose rubber mallet a few 20 times in case any air bubbles were in the lines. Installed on bike, and cut lines. Used Shimano bleed funnel, and activated levers to get bubbles to leave system. Rotated lever 90 degrees each way per instructions. I did not open caliper bleed nipple. Rode the crap out of Tahoe for 3 days without any issues. These 8000 series are definitely an improvement over 785 series, barely. They are just a bit better modulating. I am very happy with these new brakes. Little sticker is ke oc.
    Attached Thumbnails Attached Thumbnails M8000 brake "pumping up" on DH-image.jpg  


  154. #154
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    Quote Originally Posted by hoolie View Post
    Click image for larger version. 

Name:	image.jpg 
Views:	134 
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ID:	1070344I opened package of 2 new 8000 brakes. Hung from lever, so the brake lines were perpendicular to planet Earth, tapped caliper and hose rubber mallet a few 20 times in case any air bubbles were in the lines. Installed on bike, and cut lines. Used Shimano bleed funnel, and activated levers to get bubbles to leave system. Rotated lever 90 degrees each way per instructions. I did not open caliper bleed nipple. Rode the crap out of Tahoe for 3 days without any issues. These 8000 series are definitely an improvement over 785 series, barely. They are just a bit better modulating. I am very happy with these new brakes. Little sticker is ke oc.
    Just how were you able to push the air without
    Opening the caliper end and push the fluid from that end?

  155. #155
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    It's not hard, air floats on fluid. Air will always work it's way to the top of fluid. So what he did was the simplest and frankly smartest way to do it. Let physics and gravity do the work. This way the fluid doesn't risk get aerated during the bleeding process.

    It's how I ensure my rear brakes don't have air. Hang the bike by the front wheel for a day or 2 and check the reservoir to make sure it's still full and let any trapped air out.

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  156. #156
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    As Tigris99 said, I did not do a complete bleed. I hang brakes before install. Tap. Get any potential bubbles out of calipers by tapping and changing angles. Try to get bubbles to rise to levers. I have no evidence this works. Then put the new brake set onto the bike. Cut lines, reinstall with new barb/olive. Then hook up bleed funnel, just to let air escape from top of system, and lever gets firm. A few bubbles always come up through funnel. Maybe my newer brakes are just different than people at beginning of thread? That's why I added the code letters in above posting. But they are sweet!
    Last edited by hoolie; 05-15-2016 at 07:42 AM.

  157. #157
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    Reporting back in, brakes installed on new bike and have zero pump issues. Got a good ride in today with downhill chunk, no issues. Just a nice firm lever. Lines were trimmed by LBS, no idea what bleed method they used but feels great.

  158. #158
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    Quote Originally Posted by gasmanxj View Post
    Reporting back in, brakes installed on new bike and have zero pump issues. Got a good ride in today with downhill chunk, no issues. Just a nice firm lever. Lines were trimmed by LBS, no idea what bleed method they used but feels great.
    have you gone through rough descents?

    what's the code in the sticker underneath?
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  159. #159
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    Quote Originally Posted by spyghost View Post
    have you gone through rough descents?

    what's the code in the sticker underneath?
    And is it the white piston or black?
    My 9020 with the black piston still doing the same thing
    While the front one with the white piston didn't have the pumping issues

  160. #160
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    I doubt the color of the piston has anything to do with it. You've got air trapped, a line not correctly sealing (not clean when installed or not tightened correctly) or your lever plug/cap isn't sealed.

    Of course there is a slim chance of something being wrong with caliper but very slim chance of that unless you can see evidence of fluid leaking around the pistons.

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  161. #161
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    On my set it did
    Front one with white work like it should be. No bleeding needed
    Back one with black, bleeded multiple times, still pumps
    Time to call shimano again

  162. #162
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    Quote Originally Posted by spyghost View Post
    have you gone through rough descents?

    what's the code in the sticker underneath?
    Yup, chunky descent on a trail that causes the pump on my other bike. Codes are NJ rear, OA front.

    Quote Originally Posted by digifun View Post
    And is it the white piston or black?
    My 9020 with the black piston still doing the same thing
    While the front one with the white piston didn't have the pumping issues
    White pistons. I'll continue to report back, might be headed to Sedona this weekend so will be a good test.

  163. #163
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    20 miles in Sedona yesterday with plenty of rocky downhill, drops, etc. No hint of pump up, brakes performed flawlessly. Either I got a good set or they fixed something. Either way I'm happy. Now if I could only get the 8000's on my other bike to perform the same way!

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    I too have developed pump up in my rear brake after just under a year of having them. They are "NE" code levers and I have just tried bleeding the rear again today. Interestingly, at the final stage when you periodically open the calliper nipple while pumping the lever, I noticed an unusual behaviour. If you don't let the lever return completely you can move the lever freely in its stroke. There is a reluctance for the master cylinder to fully extend, and hence the lever. I wander if this is showing something wrong inside the lever? I guess I'll warranty it anyway to see what can be done. Wish I'd gone saint now!

    Edit: further to the above, doing the old trick of taping the lever to the bar has a similar affect - the lever gets slacker with time and doesn't firm up until it is allowed to fully extend. Implies air in system, but I bled it properly!

  165. #165
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    Quote Originally Posted by gmt198 View Post
    I too have developed pump up in my rear brake after just under a year of having them. They are "NE" code levers and I have just tried bleeding the rear again today. Interestingly, at the final stage when you periodically open the calliper nipple while pumping the lever, I noticed an unusual behaviour. If you don't let the lever return completely you can move the lever freely in its stroke. There is a reluctance for the master cylinder to fully extend, and hence the lever. I wander if this is showing something wrong inside the lever? I guess I'll warranty it anyway to see what can be done. Wish I'd gone saint now!

    Edit: further to the above, doing the old trick of taping the lever to the bar has a similar affect - the lever gets slacker with time and doesn't firm up until it is allowed to fully extend. Implies air in system, but I bled it properly!
    Common Shimano lever problem. The brake master cylinder becomes sticky in the bore. Seen loads of levers fail this way.

  166. #166
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    Quote Originally Posted by gmt198 View Post
    I too have developed pump up in my rear brake after just under a year of having them. They are "NE" code levers and I have just tried bleeding the rear again today. Interestingly, at the final stage when you periodically open the calliper nipple while pumping the lever, I noticed an unusual behaviour. If you don't let the lever return completely you can move the lever freely in its stroke. There is a reluctance for the master cylinder to fully extend, and hence the lever. I wander if this is showing something wrong inside the lever? I guess I'll warranty it anyway to see what can be done. Wish I'd gone saint now!

    Edit: further to the above, doing the old trick of taping the lever to the bar has a similar affect - the lever gets slacker with time and doesn't firm up until it is allowed to fully extend. Implies air in system, but I bled it properly!
    It's all spelled out above. Done deal. You have the bad production model. No need to buy Saints. Call Shimano and explain your issue to the warranty department and follow their lead. You'll have an updated and perfectly normal working set of M8000 brakes in short order. Case closed.

  167. #167
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    M8000 brake "pumping up" on DH

    Anyone have # for Shimano warranty? I've got 2 sets of XT M8000 that have the pump up.

    Edit: is this the number (Shimano American Corp) people have called:
    http://bike.shimano.com/content/sac-...ontact-us.html

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  168. #168
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    800-423-2420 is the number I called when I handled my issue 2 weeks ago. That's their So Cal Nor Amer HQ I believe.

  169. #169
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    Cool thnx bro

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  170. #170
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    Got my replacement XT's (took less than a week through Shimano warranty!!) and got a chance to ride them properly yesterday. Holy crap it's a night and day difference in feel from my old ones. New ones have both OE code. Old ones had ND (front) and NC (rear).

    My 'N' set, even after multiple careful bleeds, always felt a tad spongy and never got super firm. They were ok. But after riding these new 'O' code ones (which btw I had to bleed after shortening the hoses - so can't attribute anything to factory bleed) holy **** do they feel nice and firm. Bite point is nice and consistent. Always at the same spot. No weird pump up sensation at all. Less effort overall for a full ride. Will be nice at the bike park where braking so much fatigued my forearms.

    Overall, I can't say enough how well Shimano has handled this. I dare say these are now the best feeling brakes I've ever ridden! It totally changes the ride, as don't have to think about brakes at all. Just have to get used to having consistent and firm bite point lol!

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  171. #171
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    Seeing as this thread is still alive, I'll add a data point.

    I had a brake failure (lever went to the bar) on M985 XTR trail on an Enduro event. The event had a Shimano neutral service tent after stage 1. They diagnosed a leaking master cylinder and swapped on an M8000 FOC. The new MC exhibited the pump up behaviour. No code label on the MC.

    Even after multiple bleeds, the inconsistent behaviour remained. Riding the Pleney black run in Morzine (rough, steep), the pump up was entirely consistent and would happen in every situation where I: 1) applied the brakes, 2) partially let off the brakes and 3) re-applied. I used it as a prompt to release the brake fully and let it recover momentarily. As this was run I knew well, this wasn't an insurmountable problem but eventually it was too annoying. I bought SLX brakes (M675, old lever design) and swapped just the lever. Problem solved.

    So my data point is that the problem is a lever problem. Nothing else.

    The pump up was between running the reach close to the bar and the bite point migrating to full reach of the lever and going solid (i.e. before the servo-wave had done its stuff). Early on experiencing this it was enough to give me a wrist tendon strain when I went to grab brake and the forces built up so unexpectedly.

    I reckon the problem is the relief port in the MC restricting fluid returning from the hose/caliper. I might do some investigating seeing as I have an MC with no value and no warranty.

  172. #172
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    The problem and fix was identified already by Shimano. It was the lever which they made changes to and solved the issue.

  173. #173
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    Quote Originally Posted by thegweed View Post
    Thanks. NC rear and ND front, no problems whatsoever...but there's no downhill here in Florida. No problems at the Kerr Scott trails either.
    I have the same codes and experience brake lever pump on both front and rear. The rear is worse than the front. I had the brake almost eight months. I thought it was a bleeding issue until I found this thread. I'm going to try to return them to Jensen USA first then deal with Shimano as a last resort.

  174. #174
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    If the levers are the problem, do the race models have the same issue? And do you need to go xtr to not have the servo wave, or or there lower end models without?

    Also I was wondering if Saint or Zee levers work? They are servo wave but I always hear that these brakes have better modulation despite the increased power.

  175. #175
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    For best modulation use hope brakes.

  176. #176
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    Anyone tried upgrading to Goodridge hoses (steel braided lines) as a possible fix to this?

  177. #177
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    You're not going to fix anything by messing with them and throwing $$ at them. The problem is identified and remedied by Shimano's redesign of the lever's interior mechanism.

  178. #178
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    Do anyone knows what was changed?

  179. #179
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    Quote Originally Posted by Oh My Sack! View Post
    You're not going to fix anything by messing with them and throwing $$ at them. The problem is identified and remedied by Shimano's redesign of the lever's interior mechanism.
    The problem is nobody actually knows when the design change went into effect. I have a set of 2016 brakes that exhibited the behavior currently going through warranty process with Jenson USA.

    Decided not to roll the dice on the replacement set being any better and bought a set of Hopes.

    Speaking of Jenson, has anyone who bought m8000s from them gone through the warranty process? They have had my brakes for a few weeks and I haven't heard anything back from them and that's not for a lack of me trying to call in for a status update. Not very pleased.

  180. #180
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    Does anyone know if the xtr race levers ever had this problem? I was thinking of getting a set anyway but don't want to bother if I have to try to get the latest batch.

  181. #181
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    Quote Originally Posted by TooMuchCoffeeMan View Post
    Anyone tried upgrading to Goodridge hoses (steel braided lines) as a possible fix to this?
    Fair enough.

    Though It's like $15 for steel lines, and I won't be bikeless waiting for the warranty. Plus it's a substantial performance upgrade long term.

    Reason I ask is once upon a time I had a Hayes brake that had the same frustrating bite point issue as my current XT and I eventually solved it with a Goodridge line.

    My buddy at the time was on XT's and also upgraded to Goodridge hoses, he reported that it solved his migrating lever issue as well.

    This was years ago on unrelated brakes though, just wondering if anyone has tried steel braided lines lately and if it helped.

    I've managed to fix my front brake bite point using that "5 minute bleed" procedure (Tech Spotlight - 5 Minute Bubble Bleed - Pinkbike), but the rear just can't be fixed like many have experienced. I've bled the rear multiple times, same results. (I've owned and bled many different brakes, I even used to do the problem bleeds for the shop by my house. Like many here, I know what I'm doing, it's just not happening).

    Same numbers on both front and rear levers btw, only difference is hose length.

  182. #182
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    I did have the same problem with XTR M9000 race brake! Bleed, re-bleed and repeat.....problem never solved!
    Quote Originally Posted by NWRyder View Post
    If the levers are the problem, do the race models have the same issue? And do you need to go xtr to not have the servo wave, or or there lower end models without?

    Also I was wondering if Saint or Zee levers work? They are servo wave but I always hear that these brakes have better modulation despite the increased power.

  183. #183
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    I suffered this issue with XTR M9000 Race brakes as well! So sad.......

    Quote Originally Posted by NWRyder View Post
    Does anyone know if the xtr race levers ever had this problem? I was thinking of getting a set anyway but don't want to bother if I have to try to get the latest batch.

  184. #184
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    Quote Originally Posted by socaltrailrider View Post
    My replacement set that work well are NI. I wonder if the lettering is sequential and the "I" is a newer manufacturing batch than the "G".
    N = 2015
    G = July

  185. #185
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    Follow up to post #154. Went to Tahoe again, I don't know if altitude has any effects on these brakes, but winter deadfall can wreak havoc on spokes! Broke a spoke, either hit a side boulder, or a stick caught up in rear wheel. Anyway, flipped bike upside down on trail, wrapped spoke around some other spokes, finished climb. Well, an air bubble moved around, and I had NO front brake for about 15 min of climb. It was very frustrating, and I was fast tapping lever, bouncing front wheel, holding lever, all to try to get air bubble to move. I was getting a little worried, as I had a 3000 ft, 40 minute Downhill coming up (Armstrong Pass, Armstrong Connector, Sidewinder). Finally, I got lever feel back, and had to readjust lever reach to where I had it originally. Brakes back online! So, the point of this story, is these brakes are really not easy to bleed. Something about this new design traps air worse than any previous XT brakes. I love 'em, but need to figure this aspect out.

  186. #186
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    On a side note, as I am getting older 48, my hands are getting a tad arthritic, and my next brakes will be SAINT. It's overkill for my home trails, and a waste of $, but 2 weeks ago I rode Magura 4 piston DH brakes in Tahoe (shuttle DH), and after 5 hours, my hands were noticeably less fatigued. The DH brakes don't slow you down much faster, it's just a little easier lever feel, all day long.

  187. #187
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    Got mine early on, but forgot where I bought them from! Had the pump up problem on the rear first but now the front has started to do it too. Think the front actually pumps up enough to engage the brake slightly. Rear lever has also developed a click at the start of the lever travel.

    I'd exchange if I could remember where they came from, but as I can't its time for some Hopes.

  188. #188
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    Quote Originally Posted by PabloGT View Post
    Got mine early on, but forgot where I bought them from! Had the pump up problem on the rear first but now the front has started to do it too. Think the front actually pumps up enough to engage the brake slightly. Rear lever has also developed a click at the start of the lever travel.

    I'd exchange if I could remember where they came from, but as I can't its time for some Hopes.
    Same. I've run a pair for over a year and the issues reach a "braking" point last weekend. Trying to find receipts for warranty, but i'm going back to Hopes.

  189. #189
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    Hi, i got a new bike on summer with m8000 brakes. I got the "pumping issue" on my rear one. Then i got both levers changed in warranty and then trade the brakes immediately with a sram xo set. Now i ordered the m8000 again cause i dont like the power of XO's. The question is, is there any way to check if the levers are the "revised" or the old ones? Thank you.

  190. #190
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    So, i received the brakes, the one say ke/od and the other ke/og. Are those the revised one?

  191. #191
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    Should be... anything 'o' would be 2016... the 'n' (2015) seemed to be the problematic ones

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  192. #192
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    Quote Originally Posted by Jayem View Post

    When you say "pumping up", that usually refers to one of two things: The engagement point moving out, to the point where the brake will eventually just lock up without even pulling the lever. [...]

    The other "pumping" that people often refer to is a lack of power, where the lever goes to the bar, or at least the engagement point is far in, and you have to "pump" the brakes several times to either get an engagement point, or move it away from the handlebar to where you can get good "bite". [...]
    After going through the many threads on this topic, bleeding multiple times, etc, I guess I finally solved my "type 2" pumping issue (i.e fluctuating bite point)
    I noticed that the white ceramic pistons much easier to retract than other brakes, like the seals are looser or the piston surface is smoother or slicker.
    This may be too much of a good thing, since I believe the spreader spring will have enough force to (slowly) spread the pads apart when the brakes are left idle for a few minutes.

    In other words, the pads are very slowly "creeping" open by the effect of the spreader spring. Especially when the pads show some wear and and the spreading force is greater.

    I validated my theory by reducing the gap of the spreader springs from 18 to approx 12 mm thus reducing the spreading force, and reinstalling the same old pads with no other changes done to the brakes.
    After 2 days of hard riding I have to report that the bite point remained consistent with no pumping or adjusting required.

    - I am not sure this will be the cure to the issues other readers are having, but I encourage to try since the fix can be completed in a few minutes for both brakes.
    flyMTBfish

  193. #193
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    rOCktoberfest 2015 pt I here
    rOCktoberfest 2015 pt II here

  194. #194
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    Quote Originally Posted by Ausable View Post
    After going through the many threads on this topic, bleeding multiple times, etc, I guess I finally solved my "type 2" pumping issue (i.e fluctuating bite point)
    I noticed that the white ceramic pistons much easier to retract than other brakes, like the seals are looser or the piston surface is smoother or slicker.
    This may be too much of a good thing, since I believe the spreader spring will have enough force to (slowly) spread the pads apart when the brakes are left idle for a few minutes.

    In other words, the pads are very slowly "creeping" open by the effect of the spreader spring. Especially when the pads show some wear and and the spreading force is greater.

    I validated my theory by reducing the gap of the spreader springs from 18 to approx 12 mm thus reducing the spreading force, and reinstalling the same old pads with no other changes done to the brakes.
    After 2 days of hard riding I have to report that the bite point remained consistent with no pumping or adjusting required.

    - I am not sure this will be the cure to the issues other readers are having, but I encourage to try since the fix can be completed in a few minutes for both brakes.
    I beleive this exact solution is buried in this very thread somewhere.

    Does anybody know if the saints have this issue?
    It is no measure of health to be well adjusted to a profoundly sick society.

  195. #195
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    Has it been confirmed that Shimano has fixed this mess on all new brakes? Or are bad brakes still out in the wild to be purchased? Seems to me like people still need to address newly purchased brakes given what I'm reading in M8000/M9020 threads.

    I need a new pair of brakes and would rather stick with my known brand/feel (and I know how to bleed easily).

  196. #196
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    IMO, you'd have to be buying from a very, very low volume dealer to get an early N-series brake set, now. My buddy just bought 8 sets from Bike-discount and I checked them yesterday and they are OI series. This applies to M8000 XT's. I can't speak to the 9000 series as nobody I know are running those.

  197. #197
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    Quote Originally Posted by Oh My Sack! View Post
    IMO, you'd have to be buying from a very, very low volume dealer to get an early N-series brake set, now. My buddy just bought 8 sets from Bike-discount and I checked them yesterday and they are OI series. This applies to M8000 XT's. I can't speak to the 9000 series as nobody I know are running those.
    Thanks, I figured this problem has been known for over a year and they would have taken steps to deal with it, but some of these threads make you think otherwise.

  198. #198
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    Quote Originally Posted by Ausable View Post
    After going through the many threads on this topic, bleeding multiple times, etc, I guess I finally solved my "type 2" pumping issue (i.e fluctuating bite point)
    I noticed that the white ceramic pistons much easier to retract than other brakes, like the seals are looser or the piston surface is smoother or slicker.
    This may be too much of a good thing, since I believe the spreader spring will have enough force to (slowly) spread the pads apart when the brakes are left idle for a few minutes.

    In other words, the pads are very slowly "creeping" open by the effect of the spreader spring. Especially when the pads show some wear and and the spreading force is greater.

    I validated my theory by reducing the gap of the spreader springs from 18 to approx 12 mm thus reducing the spreading force, and reinstalling the same old pads with no other changes done to the brakes.
    After 2 days of hard riding I have to report that the bite point remained consistent with no pumping or adjusting required.

    - I am not sure this will be the cure to the issues other readers are having, but I encourage to try since the fix can be completed in a few minutes for both brakes.
    This was discussed post #44-#59, good to see it's worked for somebody else too.

  199. #199
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    Is this still a problem on the brakes currently available?
    Formerly Travis Bickle

    Team Robot. "modulation is code for I suck at brake control. Heres a free tip: get better."

  200. #200
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    Quote Originally Posted by Travis Bickle View Post
    Is this still a problem on the brakes currently available?
    I have not heard of any issues in a long time. I'd think we'd be seeing a buzz about it here on the site if so.

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