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  1. #101
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    Re: Shimano XT M775 Wheelset Freehub fails ?

    Another ring to consider, buy a whole hub off of e bay. Then use the freewheel from that. Leaves you with a backup axle, spacers, caps and such. And you wanted the extra hub body as a cool desk accessory.

  2. #102
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    Yeah, I did this. I bought 2 XT hubs from Chain reaction because it was better value than buying a freehub alone (Also bought 2 rear wheels and countless freehub boddies).

    Trouble is, they were both faulty from NEW, like every single Shimano freehub I have owned in the last 10 years or so, they would occasionally slip 1 pawl / ratchet during every ride. Just enough to ruin confidence in the bike, and ruin the ride.
    Stay away from every Shimano XT or similar rear hub from early 2000's right up to those from as late as 2012 (after that date, or SLX models etc I cant comment).

  3. #103
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    add another to the list. i cracked a 785 freehub just the same as the rest of you. i have enough spare parts to rebuild twice so we'll see how long that lasts. i should have just bought chris king from the start. more money sure, but, you never have to worry about them breaking

  4. #104
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    Quote Originally Posted by racebum View Post
    i should have just bought chris king from the start. more money sure, but, you never have to worry about them breaking
    buy the best, you'll always be happy with what you got.

    I got mine used from fleabay, sent them to CK for a rebuild. good as new, cheaper than new. Colors don't match though. oh well.
    My bike MCA kinda climbs like a billy-goat. WOO WOO!

  5. #105
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    I've also had two M785 hubs fail in this way. I'm about to replace the second one. Does anyone know of any non Shimano hub that's the same dimensions as the M785 so I can use the same spokes?

  6. #106
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    Quote Originally Posted by 4wdphil View Post
    I've also had two M785 hubs fail in this way. I'm about to replace the second one. Does anyone know of any non Shimano hub that's the same dimensions as the M785 so I can use the same spokes?
    don't re-use spokes.
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  7. #107
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    It's totally OK to reuse spokes if all of the following conditions are met:

    1. High quality of wheel build (spoke tensions are high, equal per side, and stable over time).
    2. Spoke tensions have been checked and restored soon after every incident that could damage the rim or the spokes directly.
    3. There was no damage done to spokes by foreign objects entering the wheel, such as trying to pedal with chain derailed from the biggest cog, tree branches, rocks, another bike's pedal in bike collision, being kicked by a horse (also a real case from my practice), etc. Any spokes left intact in a wheel that suffered spoke collision, can still be reused if all other listed conditions hold.
    4. There were no spoke fatigue failures in the wheel.


    4wdphil,
    I don't recall many hubs having effective flange diameters similar to Shimano's 44-ish mm on both sides. Centerlock versions of DT Swiss 240S or 350 should work. If you choose a typical Taiwanese hub (they tend to have effective flange diameter of 58 mm on both sides), your spokes are going to be too long by 1.5-2 mm on each side. That's no reason to avoid reusing them unless they were already too long in the original wheel. I'd take brass nipples for such a build.
    Last edited by J. Random Psycho; 11-06-2015 at 10:11 AM. Reason: added 4th condition for spoke reuse

  8. #108
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    Thanks, much appreciated Random Psycho.



    J. Random Psycho;12294361]It's totally OK to reuse spokes if all of the following conditions are met:

    1. High quality of wheel build (spoke tensions are high, equal per side, and stable over time).
    2. Spoke tensions have been checked and restored soon after every incident that could damage the rim or the spokes directly.
    3. There was no damage done to spokes by foreign objects entering the wheel, such as trying to pedal with chain derailed from the biggest cog, tree branches, rocks, another bike's pedal in bike collision, being kicked by a horse (also a real case from my practice), etc. Any spokes left intact in a wheel that suffered spoke collision, can still be reused if conditions (1) and (2) hold.
    4. There were no spoke fatigue failures in the wheel.


    4wdphil,
    I don't recall many hubs having effective flange diameters similar to Shimano's 44-ish mm on both sides. Centerlock versions of DT Swiss 240S or 350 should work. If you choose a typical Taiwanese hub (they tend to have effective flange diameter of 58 mm on both sides), your spokes are going to be too long by 1.5-2 mm on each side. That's no reason to avoid reusing them unless they were already too long in the original wheel. I'd take brass nipples for such a build.[/QUOTE]

  9. #109
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    I always heard these things broke a lot. Mine has almost 1000miles on it now and its still going strong. I bought a back up freehub just incase but so far its been good.
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  10. #110
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    I have had 3 of these XT hubs fail on me over the last few years. Simply put, junk. The last one started it's popping/skipping on my trainer! I have Chris King on the MTB now and I'll have to build up new wheels for the Surly next. Other 29er wheel is in the spares pile. So, one 26 mtb, one 29 mtb and one 700/29 road/gravel bike.
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  11. #111
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    As a curiosity, have you ever serviced (lubricated) the Shimano freehub? When I still had Shimano freehubs, I performed regular maintenance and lubrication and managed to never have a failure for more than 10,000 miles. Given the many failures of these freehubs, I might have just been lucky.
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  12. #112
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    Quote Originally Posted by Cleared2land View Post
    When I still had Shimano freehubs, I performed regular maintenance and lubrication and managed to never have a failure for more than 10,000 miles.
    Which models were the hubs (basically, did they have steel or aluminum axles)?

  13. #113
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    I think these were all steel axles. However, I don't think this would have any effect on the freehubs. Do you believe differently?
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  14. #114
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    I saw freehubs on aluminum axle Shimano hubs fail much quicker than on steel axle ones. Pawl shape is very different, thinner and wider on the former. And the way they are sprung isn't convincing either.

    Shimano has also taken measures to complicate freehub maintenance on aluminum axle models. The inboard seal isn't removable any more and the cup is harder to unscrew without breaking it.

  15. #115
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    Lubricating a Shimano Freehub without disassembly

    In this case, I'm lubing with a very light Freehub specific grease, but, the syringe can inject any lubricant (liquid or grease) that you prefer.

    Shimano XT M775 Wheelset Freehub fails ?-img_6765.jpg

    Shimano XT M775 Wheelset Freehub fails ?-img_6766.jpg

    Shimano XT M775 Wheelset Freehub fails ?-img_6768.jpg

    Shimano XT M775 Wheelset Freehub fails ?-img_6769.jpg

    Shimano XT M775 Wheelset Freehub fails ?-img_6770.jpg
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  16. #116
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    I've never had a Morningstar tool, alas. I simply use elbow grease and a can with kerosene.

    The aluminum axle type freehubs need a less viscous grease than what they come with indeed (ideally an oil bath) or just some 1 ml of heavy gear oil. And more frequent maintenance than the steel axle type.

    Still, regular maintenance can only prevent pawl/teeth failure scenarios, not the entire freehub body cracking.

    Edit: fixed typo
    Last edited by J. Random Psycho; 02-29-2016 at 12:39 PM.

  17. #117
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    did shimano ever explain why the alu axle hubs cracked? Was it a sh1tty design or was it some heat treat problem?
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  18. #118
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    Quote Originally Posted by J. Random Psycho View Post
    Still, regular maintenance can only prevent pawl/teeth failure scenarios, not the entire freehub body cracking.
    No doubt on the freehub body cracking and I have seen a few of those here on MTBR.
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  19. #119
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    Is this still an issue on XT hubs. They are so cheap and I don't mind cup/cone but damn there seems to be alot of horror stories.

  20. #120
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    Quote Originally Posted by dundundata View Post
    Is this still an issue on XT hubs. They are so cheap and I don't mind cup/cone but damn there seems to be alot of horror stories.
    Maybe it's a total crap shoot? I've been running on M775 XT since I had my wheels built in 2010 with absolutely ZERO issues. I'm a Clydesdale , and I ride hard. But I also live in the desert and seldom do mud.

  21. #121
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    Shimano XT M775 Wheelset Freehub fails ?

    I got a bike with shimano rm35 hubs for commuting. First year blew a free hub light trail riding. Then the next year split the freehub body trail riding. Lbs put a slx on and it worked for the rest of the summer. This spring i blew it on a steep short hill i was sprinting. Then i got a replacement and blew it in one ride.....

    Lbs sold me a sun ringle black flag wheel as i was in a xc race that sunday and it lasted 2 xc races and 5 weeks of riding and i snapped the pawls in it on a short sprint climb.

    Also last winter i snapped the pawls in my farley in the fall, then chipped one this spring. I break stuff. On the fence on a 350 big ride or a onyx hub for the farley for this winter.
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  22. #122
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    I have the 756 so I'll see how it goes. might start building up some new wheels just incase with hope or dt swiss.

    funny enough years ago I rode some cheap Shimano hubs probably Alivio for quite awhile with no issues.

  23. #123
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    The Shimano hub pictured in post #115 above has just over 10,000 trouble-free miles on it. I realize this has not been the case for many here, but for me personally, it has been issue free. I have another one with about 2,600 miles on it and it too, has been trouble-free.

    I believe ongoing freehub maintenance (as shown in post #115) could have played a role in avoiding internal self-destruction, but the cracking of the splined freehub bodies are not preventable.
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  24. #124
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    I know this is an old topic, but I suspect the freehub on my M-776 wheelset is dying. It's got a bit of a crunch in it and a faint knock sound at the same point in every rotation. Is there a freehub out there thats more reliable I can replace this dying one with? Just curious if anyone has found a permanent fix for this?

  25. #125
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    There is no "permanent fix" besides new hubs. All freehubs wear out. Your issue isnt the one most have. There was a time that the freehub bodies were actually splitting in half.

    Freehubs dont last forever, and even less when not maintained.

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  26. #126
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    Quote Originally Posted by OverlyCasual View Post
    Just curious if anyone has found a permanent fix for this?
    Regular maintenance and service perhaps.

    Quote Originally Posted by RAKC Ind View Post
    There is no "permanent fix" besides new hubs. All freehubs wear out. Your issue isnt the one most have. There was a time that the freehub bodies were actually splitting in half.

    Freehubs dont last forever, and even less when not maintained.
    You don't have to buy new hubs, you can just replace the freehub.

    Splitting Shimano freehubs remains an issue for some.

    I have had some Shimano freehubs roll more than 10,000 miles with a regular service schedule. With the right tool, it's complete and easy.
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  27. #127
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    Well he asked for "permanent fix" which a different hub is the only possible way of that lol.

    Ive never had problems either myself, but i rebuild all mine with marine grease when its time to service them.

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  28. #128
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    Thanks guys. I'm not even sure it's the freehub body honestly, my hub just may need some love. I just wanted to get an idea of what kind of action I would need to take if it were my freehub body.

  29. #129
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    I had already been thinkin' it could be something else, but we be rollin'.
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  30. #130
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    I think having the freehub fixing bolt too tight can crack the shell. I've seen them easily over 100 ft lb. They're supposed to be around 25 I think.

  31. #131
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    Man up
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  32. #132
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    The factory i have seen tighten the shit out of them. Broken allen wrenches trying to get them loose.

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  33. #133
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    But freehub shell isn't under compression from the bolt. Freehub core is, and it's a very beefy part.
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  34. #134
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    I wasnt saying it had any effect but they do way overtighten the hell outta it, makes service or replacement a nightmare.

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  35. #135
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    Shimano calls for something like 30 - 50 Nm of torque. That's tight. 40 Nm is about 360 in. lbs.
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  36. #136
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    Quote Originally Posted by J. Random Psycho View Post
    I saw freehubs on aluminum axle Shimano hubs fail much quicker than on steel axle ones. Pawl shape is very different, thinner and wider on the former. And the way they are sprung isn't convincing either.

    Shimano has also taken measures to complicate freehub maintenance on aluminum axle models. The inboard seal isn't removable any more and the cup is harder to unscrew without breaking it.
    Very illuminating! thank you JRP. Was about to buy some shimano xt M8000 or similar preceding M785 hubs to get the centerlock feature and lighter weight.

    These are aluminum axle. Have you worked on these particular models and they are like this?

    Just so to be sure , you're saying I would not be able to relube this ( have no freehub buddy tool) cause can't remove rear seal? Also, much less likely I'd be able to remove cup and if not rebuilding would be impossible.

    If I got this right, would be very tempted to just go back to the old M756 and settle for 6 bolt rotors and 3 oz more per wheel and low # engagement points. Damn.

    All the supposedly top quality hubs like CK and Hopes seem to noisey. I'm in the country and enjoy coasting down the hills I labor up, enjoying the land in silence.

    Your experience is amazing. Are you a pro wrench?

  37. #137
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    Xtr 9010 are the hubs you want. I have used those going down ski lift downhill courses. They can take a beating and they roll really fast. As for the cheap stuff the XT 8000 I have not heard of any failures on like I did the older 785. Shimano apparently changed the metal in the later generation of 785 and it solved the cracking problem
    Last edited by racebum; 4 Weeks Ago at 10:34 AM.

  38. #138
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    Quote Originally Posted by racebum View Post
    Xtr 9010 are the hubs you want. I have used those going down ski lift downhill courses. They can take a beating and they roll really fast. As for the cheap stuff the XT 8000 I have not heard of any failures on like I did the older 785. Shimano apparently change the metal in the later generation of 785 and it solved the cracking problem
    Will look at xtr. Thanks.

    They are as quiet as old m756?

    Still, want the ability to relube and rebuild so will wait to see what Random Psycho says. Do you know if the XTR 9010 is like he describes?

  39. #139
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    I really have no idea on the rebuild. You used to be able to take the freehubs apart but I have not had to since I started running these. If you want that fast angular contact bearing XTR is the way to go and the freehub has been trouble free. The dt240 is also completely serviceable but it's more money and the bearings don't roll as smooth as XTR. You can get them in the same ballpark but it requires a $200 bearing upgrade and they will not last as long as the previously mentioned XTR
    Last edited by racebum; 4 Weeks Ago at 10:33 AM.

  40. #140
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    Carlt1...

    If your budget is in the XT/8000 range, then you might find yourself paying about 4 times the price of XT/8000 to shave some weight. If you're looking at spending $400 and up for hubs, your options open up significantly.

    Will you be performing all maintenance and service on these hubs? Just note that the Shimano's are Cup and Cone. These can really be dialed in for excellent smoothness, but it will require some effort on your part. Most other hubs will be Cartridge Bearings and these are easily serviced but with no concerns for fine tuning the bearing pre-loading.

    DT Swiss 350's are an excellent bargain with complete ease of servicing. Far less expensive than the high-end 240's.

    If a quiet freehub is your preference, a Shimano is tough to beat. Servicing them is easy enough, especially with a Freehub Buddy. They are not expensive and seem to be available again. Most other hubs (star ratchet or pawl freehubs) can be be easily maintained and serviced easier than a Shimano.

    Define your budget and go from there.
    Last edited by Cleared2land; 4 Weeks Ago at 12:49 PM.
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  41. #141
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    100% agree with cleared

  42. #142
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    Hi Cleared2land

    It seems the main point of my post is being missed

    I have used and maintained M756, the non A model for many years.

    I was responding specifically to 2 points J. Random Pscho made about the new Shimano aluminum axle hubs with the increased POE of 36 as in the M785/M8000

    #1--With such hubs you can no longer remove inner seal. This would mean that one could not pour oil in back to lubricate or solvent to clean, like I have with my M756. Since the Freehub buddy (FHB) you discuss is no longer available this seems a major downside. Also maybe FHB can't be used on m8000. If could find used

    Do you know if fits m8000?

    #2--Can no longer reliably remove bearing cup from front in order to disassemble freehub with the tool made from an old socket. Think was "RJbikeguy" ? on yt telling how to make tool.

    So I asked him or anyone with experience to confirm these 2 points like has he tried all this on M8000 and do I have consequences correct.

    Because if correct these points, especially #1, would be major reasons to avoid M785/m8000. Would prefer CL and lower weight but not at this cost.

    If you or anyone has access to these hubs and can experiment please do or ask some friend who knows and report. In case JRP doesn't reply

    My reading of your posts, perhaps incorrectly ?, was that you have only used/seen the steel axle hubs like m756

  43. #143
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    Paul Morningstar's Freehub Buddy is available...

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  44. #144
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    I do work on bikes for a living. Former programmer who quit the office job and became a freelance bike mechanic.

    Shimano has been trying to fix the early freehub failures over the years since the aluminum axle hubs came out. It looks like there is no ultimate fix, but they seem to have managed to reduce the number of failures.

    In the 785/985 generation, the mechanism is still more demanding of fresh and clean lubricant than their older 16 POE freehubs. And freehub shells still get cracked under torque in low gears by strong riders. I have little experience with the newer 8000 and 9000 generations though (yet).

    It is still possible to clean and lubricate the 36 POE freehub without disassembly (my preferred method because I use gear oil in a syringe with needle to go past the inboard seal), but it takes longer and is more involved. I rinse them in kerosene and let dry before applying oil.

    It's also often possible to unscrew the cup, but I've had instances where it cracked instead. Had no such issue with 16 POE freehubs, Shimano and other brands.

    I have never used the Morningstar tool. Well aware of it but don't have one. I think it's too invasive (needs removal of outboard seal that's not designed to come out undamaged), and overuses solvent/lubricant.

    The 756, which is currently called FH-M756A (distinguishable from 756 on the outside by design of contact seals) remains popular with local bikepackers and commuters. 10x135 SLX hubs also work nicely.
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  45. #145
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    Quote Originally Posted by J. Random Psycho View Post
    I have never used the Morningstar tool. Well aware of it but don't have one. I think it's too invasive (needs removal of outboard seal that's not designed to come out undamaged), and overuses solvent/lubricant.
    I have never had to remove a seal to lubricate them and "overuses solvent/lubricant" is synonymous with having a 'lead foot' on a throttle. Control the input.

    The amount of lubricant entering the freehub is proportional to how much you choose to inject. A little or a lot. It's even more applicable when using oils.
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  46. #146
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    They used to be the bomb but they hardly seem worthwhile anymore if you ride much at all, at least that's been my recent experience. DT's are so much less needy.
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  47. #147
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    ^^^ Less needy, and when they are needy, they're easy to service. No tools other than a chain whip if you feel that you need it. You can just leave the cassette on and accomplish your task.
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  48. #148
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    Quote Originally Posted by Cleared2land View Post
    Less needy, and when they are needy, they're easy to service. No tools other than a chain whip if you feel that you need it. You can just leave the cassette on and accomplish your task.
    I know, servicing the ratchet rings requires 5 minutes and zero tools. Someday I'll have to mess with the bearings but over 2,500 miles so far and mine still feel pristine, no adjustments required.
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  49. #149
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    Quote Originally Posted by Cleared2land View Post
    I have never had to remove a seal to lubricate them and "overuses solvent/lubricant" is synonymous with having a 'lead foot' on a throttle. Control the input.

    The amount of lubricant entering the freehub is proportional to how much you choose to inject. A little or a lot. It's even more applicable when using oils.
    The tool fit and sealed with both dust and contact seals in place?

    Either way, the idea of this tool is to flush the freehub not unlike what one does on assemblies with zerk fittings, right? With grease, that uses lots, before clean grease starts coming out. And with solvent, since the freehub is removed anyway and is being handled over a drain vessel, you can just use gravity (in absence of pressure from solvent being pushed through the tool) to let sediment settle down near the inboard seal, then let solvent through the seal, and repeat. In any case, the problem is the cleaning phase, not lubrication.
    26" rigid SS 4130 BB7 nylon-flats ESI latex-tubes non-lubricated-8spd

  50. #150
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    Correct, no seal removal, the cleaner or lubricant moves past the seals with no restriction.

    On old, well used freehubs, I've injected SafetyKleen or kerosene in the syringe several times to flush until clean then allow the freehub to dry before lubricating. Outboard gear oil works great. Wonderful tool.

    Shimano XT M775 Wheelset Freehub fails ?-img_6766.jpg

    Shimano XT M775 Wheelset Freehub fails ?-img_6768.jpg
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  51. #151
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    Is it worthwhile upgrading the body on an xt M8000 hub from Y3CZ98050 (same as on M785) to xtr Y3CN98080?

    My M8000 hub gradually died a few days ago during a 94 km xc race, so I just had to forget about freewheeling the last 30-40 km... Sometimes it would spin, sometimes not.

    This hub was nearly new, and only had something like 500 km on it. First I tried to clean and lube it, as I was hoping it was only dirt in the mechanism. That was difficult, as the inboard seal would not come off, as mentioned in previous posts. In the process it stuck completely, and I decided it was a gonner. Then fearless, with a bit of force I could remove the seal, and saw the problem: one of the bearing balls had cracked and travelled in, under the shell. There it sat in pieces, carefully preventing any further rotation of the body.

    This does not appear to be the usual problem on the Y3CZ98050 on older M785 in the early posts on this thread. The shell is not cracked, but I expect it is scratched on the inside from the ball gone rouge. Anyone else had a similar problem?

    I am still running an M756 on another bike, and have done so for over three years and at least 6000 km in both mud and dust. Have not had any problems with it, and never seen any reason to service it. It just keeps spinning like cat. I was hoping all xt hubs were like that...

    I just ordered a new Y3CZ98050 from my lbs, but if I get a vote for it I might ask them to change it for an Y3CN98080, even if that is going to cost.

  52. #152
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    Unfortunately, your issue is not unheard of and there's nothing that you could have done to prevent that type of failure.

    Warranty with an upcharge for the different P/N?
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  53. #153
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    Quote Originally Posted by Cleared2land View Post
    Warranty with an upcharge for the different P/N?
    Well, yes, perhaps. Bought it on-line at a sale price, so will think about if it is worth the trouble. Have little hope they will help me to an upgrade.

  54. #154
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    Quote Originally Posted by J. Random Psycho View Post
    ... you can just use gravity (in absence of pressure from solvent being pushed through the tool) to let sediment settle down near the inboard seal, then let solvent through the seal, and repeat. In any case, the problem is the cleaning phase, not lubrication.
    Do I understand you right, that you just keep it standing on the inboard side (outboard side up) the whole time, and inject solvent into it, wait, and then inject lubrication? Keeping the inboard seal on? I'll check on my dead body if I can get the inboard seal back on snugly, but I am not really hopeful.

  55. #155
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    I tried to remove the ds cup ONCE, on a Dura Ace 9000 hub. There were four notches in it for the tool, so I went to the hardware store and bought a socket that fit the diameter perfectly. Then I chucked it in my mill and precisely machined it until it had four exact notches. I tested it for fit and did some minor grinding so all four contacted all notch surfaces with even force.

    I cut some pine as soft jaws for my vice to hold the hub flanges.

    Then I put on some classical music, began to apply torque, then thought WAIT, this might be reverse threaded.

    Did some internet reading to find out the correct direction. Great. Put my tool in there and shattered that bastard on the first try.

    That hub now has an Ultegra freehub body.

  56. #156
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    olao,
    I keep it partially submerged in kerosene, inboard end down. All seals are left in place. I fill the freehub with kerosene from outboard end, and actuate the mechanism with fingers. Then I raise the unit above kerosene vessel, and use a needle to make a slit between inboard seal and freehub core, so the inside is drained. This is repeated several times.

    Then I set it apart to dry. In the winter, a working heater helps speed this up. Once it stops smelling intensely with kerosene, I inject about 1-1.5 ml of gear oil with a syringe from inboard side, making sure oil gets on ball bearings and on pawls (by varying needle insertion depth), and that the contact surface of seal is also oiled.
    26" rigid SS 4130 BB7 nylon-flats ESI latex-tubes non-lubricated-8spd

  57. #157
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    Olao--Since you've got a bad M8000 could you try removing inner seal and reinstalling (if came off) and report?

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    J. Random Psycho,
    thanks for the clarification! Will try that sooner or later on my 756A, when I feel it needs some love.


    Carlt1,
    ok, did that and took some photos of the parts and how I did it. It turned out that the difficult bit is actually getting it off, not getting it back on again.

    To get it off I used a small, blunt screwdriver, but had to stick it in quite deep, probably really close to the bearing itself, and push fairly hard. So, I'm still not sure I want to do this with an intact body. That it even worked in my case might be because I had one (or even two?) balls missing, and I almost think I get the screwdriver down in the gap of the missing ball. As you can see, the seal consists of a rounded (u-shaped in cross section) metal ring with a soft rubber skirt attached to it.

    Snapping it back on was really easy, and it seems to fit nicely and sit tight again.

    So, unless anyone has done this to an intact M8000 body - without damaging it - I am still not ready to say this is a safe procedure.

    Shimano XT M775 Wheelset Freehub fails ?-dsc_8814.jpg
    Inserting the screwdriver from the inside.

    Shimano XT M775 Wheelset Freehub fails ?-dsc_8810.jpg
    The seal loose on top of the body.

    Shimano XT M775 Wheelset Freehub fails ?-dsc_8811_1.jpg
    The backside of the seal.

    Shimano XT M775 Wheelset Freehub fails ?-dsc_8813.jpg
    The missing ball...

    Shimano XT M775 Wheelset Freehub fails ?-dsc_8809.jpg
    The seal put back in place.
    Attached Thumbnails Attached Thumbnails Shimano XT M775 Wheelset Freehub fails ?-dsc_8811.jpg  

    Last edited by olao; 4 Weeks Ago at 06:41 AM.

  59. #159
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    ^^^^ Good photos!
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  60. #160
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    That's really nice to know, thank you olao!
    (Exactly why MTBR forum still rocks in this era of facebook and such.)
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  61. #161
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    That retailer, bikeparts360, has not existed for years but for some reason stays up. no buy button and no contact.

    Paul Morningstar, the manufacturer, also gone. Died long time ago and not naturally. Perhaps his inventions were costing the bike parts industry too much profit

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    Ditto. Great info and Photos!!! A real solid contribution to bike world. many thanks Olao

    Moneys pretty tight but I'm now tempted to risk 60 bucks and buy one and try this. Would really hate to lose tho.

    In this vein does anyone know if possible to remove a freehub not strung in to a wheel?
    you know, because of the centerlock. I've done this on a 6 bolt freehub only cause was able to clamp the 6 bolt mount in a table vise

    Really kind of makes one hate Shimano for their unceasing attempts to make everything unrepairable

  63. #163
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    Clearedtoland. Left a reply saying your link is invalid but appeared far up list where no one. particularly you will see it as not current. Have learned you can not "reply with Quote" or your reply will be put back in time in sequence to post being replied to.

    Also can't delete my post. So guess from now on will have to not quote, which is not ideal for readers either.

  64. #164
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    Carlt1, the hub shell in between flanges is not necessarily intended to transmit that much torque (which varies from hub to hub).

    This is certainly an issue with screw-on freewheel hubs: something must hold the shell by the drive side flange do avoid damage. Perhaps not so much with Shimano HG hubs.

    If you decide to try that with a CL hub, one idea is to clamp a CL rotor in a vise (with soft jaws, possibly also with some fine grit sandpaper) as close to center as possible, and put the hub through the rotor.
    26" rigid SS 4130 BB7 nylon-flats ESI latex-tubes non-lubricated-8spd

  65. #165
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    Quote Originally Posted by J. Random Psycho View Post
    Carlt1, the hub shell in between flanges is not necessarily intended to transmit that much torque (which varies from hub to hub).

    This is certainly an issue with screw-on freewheel hubs: something must hold the shell by the drive side flange do avoid damage. Perhaps not so much with Shimano HG hubs.

    If you decide to try that with a CL hub, one idea is to clamp a CL rotor in a vise (with soft jaws, possibly also with some fine grit sandpaper) as close to center as possible, and put the hub through the rotor.
    Hey J,

    Everything else going wrong around here I thot better to wait till have little more mental energy to respond.

    Appreciate the warning. Would never have occurred to me that holding the non drive side of hub as I did only once on a 756 could injure it. Your idea of how to do a Cl if chose to take chance is also good and worth sticking in hip pocket but guess, on top of risk of removing inner seal it's all too risky to try on a new unstrung M8000.

    I would ask for clarification on couple other points you have made.

    Your description of cleaning/lubing 36 POE freehubs with non removable inner seals. You say your experience is with M785/985 generation and not with the 8000/9000 gen.

    Looking at Olao's work, does the 8000 seal look the same as 785 and as tight?
    Main thing is, the seal is not removable but you can still lift it enough to get a syringe under it? Olao had to use real force just to get it started so seems odd.

    Very interested to hear that the high engagement hubs use more lube then 16 POE, are more "needy". May be stupid, but my question is, why does an increase in # of teeth and or pawls consume more lube and what happens to lube?

    For that matter, not really sure I've noticed I've noticed lube vanishing from my 756. Gets dirty, sure. Course, there's a couple other things in life I've failed to notice also.

    Okay, 3rd question, if you're in a forgiving mood. You've noticed a real higher # of failures with High POE hubs and say the pawls are thinner and not sprung convincingly. Is this where you have noticed most failures, with the pawls or springs breaking or what?

    At this point would try some Dt 350 but fear they are noisier.

    Thank you

  66. #166
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    Carlt1,

    1.
    the freehub seal pictured looks the same as on 775-785. Its rubber lip (inner) is in light contact with freehub core, and that's where you drive the needle to inject oil. Its outer perimeter however is steel, and is press fit in freehub shell. Kind of like it's on DT Star Ratchet hubs, except these have a similar seal press fit in *hub* shell.

    2.
    It's not the amount of oil that's critical for the 36 POE hubs, but how clean the mechanism is and how frequently oil is applied. Amount needed is the same, about 1-1.5 ml.

    3. I don't recall springs breaking, only pawls and freehub shells.
    26" rigid SS 4130 BB7 nylon-flats ESI latex-tubes non-lubricated-8spd

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    Got my new freehub body today, and am ready to install it. Can I safely assume that it is lubed enough, or should I inject extra oil into it before putting it back on?

    And regarding the lube, when you say "gear oil", JRP, you are referring to standard transmission oil for cars? (sorry, I'm a Swedish academic, and my English workshop vocabulary is limited strictly to bike gear...)

    Interestingly, the only information the body came with was a little note about not mounting the inner seal upside-down. However, that was obviously not for this model, but for one with the soft lip of the seal facing outwards. Funny :-)

  68. #168
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    Yes, gear oil; that is any viscous, EP additive containing oil used in car drivetrains. I use a heavy duty one originally intended for final drives of trucks (Castrol Syntrax Longlife 75W-90).

    If that was my own hub, I'd remove new factory grease entirely and add oil as described. But this is partly to make sure the mechanism is safe at temperatures all the way down to -30..-35 C. And partly to make sure it's adequately lubricated and contains no debris that could be introduced at the assembly line (being paranoid there).

    Sometimes I just inject oil with fresh factory grease still in place.
    26" rigid SS 4130 BB7 nylon-flats ESI latex-tubes non-lubricated-8spd

  69. #169
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    Olao, many use just regular 80w-90 lower unit gear lubricant but an improvement on that is to get same stuff but marine grade, made for outboards. more water resistant I would guess, among other things.

    Just what I've heard and am currently trying. "Mystik JT4" is what I've found in auto parts store for $6 a quart. Later have seen marine Stuff that is strict 90 weight for 3x as much but haven't used it and don't what diff is if any.

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    J, wasn't asking for amount comparison but whether the high poe hub uses lube up faster as I thought you were implying and about how much faster.

    Also what happens to it? I've never noticed lube eject around my freehub

    On removing a freehub from the hub that is not part of wheel. I.e, fresh out of box. Do you think holding the driveside flange in a cushioned bench vise is safe? Initially I thot would hurt flange so held by the 6 bolt mount but as you say best to hold it on driveside

  71. #171
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    I will second adding additional lubricant. A new Shimano freehub could only benefit from it.
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  72. #172
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    Carlt1,

    I'm not sure if there's a difference between 16 and 36 POE Shimano freehubs in how fast oil gets contaminated with worn metal. But oil can also be contaminated with matter entering mechanism from the outside, or be washed out with water. The 36 POE ones seem to be more vulnerable to lack of oil resulting from this.


    As to holding hub flange in vise, no idea. But I wouldn't try that. The flange may bend under the clamping force required to develop enough friction to overcome freehub bolt torque. I'd just lace the flange to a rim with some used 2mm spokes.
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  73. #173
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    What's the urgency to mount a freehub to a hub that hasn't been laced?

    My thoughts would be to just build the wheel, then install the freehub on a completed wheel.
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  74. #174
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    I have bought a shimano freehub before that seemed okay but lubed it anyway and it got even quieter. have also taken dust shield off front of new one and noticed not really enough grease in there by my book, as in bearings fall out easy.

    so yeh, don't think they really lube or grease them enough, hoping they'll fail earlier.

    So do it

  75. #175
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    Quote Originally Posted by Cleared2land View Post
    What's the urgency to mount a freehub to a hub that hasn't been laced?

    My thoughts would be to just build the wheel, then install the freehub on a completed wheel.
    Main reason if need to replace just your freehub usually more cost effective to buy whole rear hub cause you get xtra parts for just a few bucks.

    as said have done this holding 6 bolt mount in vise once but maybe risky as J has said as holding non drive side of hub

    Also if want to buy one to try olao's trick on rear seal. See if ruins it

  76. #176
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    Ok, I got it backwards. I see what you want to do. I agree.
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    J. Random Psycho

    Your answer is very interesting. So contaminants enter easier and also water gets in easier and then drains oil out faster.

    One would think this means the high POE hubs not sealed as well, (but sure seems that inner one is stout) Do you see any evidence of more minimum level of sealing or have any other guess/theory as to why hubs are more permeable?

  78. #178
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    No, I think sealing is not worse on 36 POE ones. Contaminants don't enter easier. But the mechanism is less tolerant to contamination and lack of lubrication than the 16 POE ones.
    26" rigid SS 4130 BB7 nylon-flats ESI latex-tubes non-lubricated-8spd

  79. #179
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    Quote Originally Posted by J. Random Psycho View Post
    No, I think sealing is not worse on 36 POE ones. Contaminants don't enter easier. But the mechanism is less tolerant to contamination and lack of lubrication than the 16 POE ones.
    Got it, must have misunderstood before. Guess I better change plans and go back to 756 for new wheels. The rear weighs 3 oz more then the M8000, not sure about fronts, but if same is total 6 oz heavier. Know that seems insignificant but is already a steel v brake MT bike frame that I had a frame builder weld disc brake mounts onto once in case I ever wanted to give up rim brakes, which I now do. So bike already heavy enough. Oh well, it's probably still silly of me.

    Need to keep maintenance chores to minimum and don't want noise.

    Live to ride

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