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  1. #1
    DGC
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    DW 5 Spot RP23 mod

    So if you read my review of the DW Spot, at the end i mentioned the bottom out on the shock. I have heard only a few people mention the same thing, easy to bottom out.
    Instead of bumping the air pressure up, losing sag and losing small bump performance, I have come up with a mod that will end the ease at bottom out and keep all small bump and mid stroke plushness pretty much the same. Does not take an expensive rebuilt custom tuned shock either. Everyone of you can do this mod in a few minutes. it is very simple.
    If you remember some years ago I was making shims for the DHX air for the 5 Spot. Instead of just dumping the shock and moving onto the RP23 I wanted to try to ramp up the end of the stroke on the dhx-a, it did not fix the mid stroke wallow, but it sure made for a nice decending shock. The same idea applies here. I had throughout all the riding/testing on the DW 5 Spot done a ride or loop on the shock as stock, then lnstalled the shim and did the same ride minutes later. I did this many times to be sure the shim idea was going to be acceptable. Not only did it turn out acceptable, but the results were so good, I won't go back to the stock set up.
    All I am essentially doing is reducing the air sleeve volume. The outer large sleeve that is, NOT the main air sleeve. I will say this again later, leave the main air sleeve on the shock, it does not need to be removed.
    The shim is made of ski base material, or better known as plastic. EXACTLY 1.2mm thick. I have tried thicker, around 1.5-1.7mm and it makes it nearly impossible to get the air sleeve back on. Any ski shop has this stuff. It is quite cheap. A few bucks or maybe 5 bucks and your set. It gets sold to us ski shops in sheets and even rolls. Many thicknesses are offered so stick with the exact 1.2mm rule and you will be fine. Get an accurate set of calipers to measure, or borrow some. I have tried a few different width pieces and I found the one I will reccomend being about the best size for the average rider on the DW 5 Spot.
    The size i felt works real good is 135mm long by 20mm wide. Keep the length exact at 135mm's. My riding weight is 190 lbs., I like agressive rough technical rides with plenty of chance for small air's, so trust me this size is good to start with. If you were really having a bottom out problem and are doing lots of small drops and kickers then maybe a little wider, but make yourself known and I will tell you what I think based on your needs. I tried a 23mm wide piece, I like the 20mm better.
    First off, get enough of the materail or something similar that is plyable enough to roll up into the size of a half dollar, stiff and brittle wont work. There should be other stuff out there just about the thickness and softness as the ski base stuff i use. Plastic is all over the place if you think about it.
    Once you got the material, cut your piece with a sharp box knife, thin blades work best. Next, with the shock off the bike, release all air from the shock air valve. LEAVE the main air sleeve on the shock. Then remove big metal c-clip that sits on the end of the outer air sleeve. I use a c-clip tool and barely put any pressure on each end of the c-clip and it raises up enough to get of with your fingers from here. Then grasp the outer air sleeve and push down on it away from the top of the shock and it will easily pop right off. Clean any dirt from both ends of the air sleeve as there are 2 big air seals that need to reseal properly. Installing the shim is shown in one of my pictures, roll the shim up tight so you get get it on the air sleeve without touching the edge of the shim to the seal. Put the shim inside and at the end of the air sleeve (bottom end) in which the c-clip sits against. The other end (top end) of the air sleeve is where the air bleed hole is located, this is where air comes from the main sleeve, don't cover it up with the shim. Make sense so far?
    When you position the shim against the inside of the body and at the bottom end of the air sleeve you can actually click or press the shim ends together for a good fit, that is why I say exactly 135mm long on the shim. It will stay there securely. Then put c-clip back in place, it will sit in its groove, then air up the shock and go ride it......!!!!!!
    It is simple to do this.
    I am running about 5-10 psi. less air with the shim. Remember you are taking away air space or volume so a little less air might be what you end up with. I have been running sag right about 15 or 16mm's, about 5/8 of an inch.
    Trust me, this works damn good. Sounds a little wierd, but if both Rock Shox and Fox are using plastic spacers in their shocks then there is no reason to doubt this mod if you need a little ramp at the end of the stroke for bottom out protection.

    Remember this line...........Try it, you'll like it. """Mikey likes it and he hates everything....!!!!"""

    Any questions? Ask away.
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    OUCH...!!!!!!

  2. #2
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    At 135x20x1.2mm you get a volume reduction of 3.24cc.

    You could do what I do and squirt in an extra 3/4 of a 5cc pillow pack of Fox Fluid into the air can and get the same result. Don't even have to remove the shock from the bike to get the fluid in. I've been doing this for about 18 months and have not experienced any problems with fluid migrating into the negative air chamber or blocking the bleed hole. Ramps up the last inch or so of travel nicely.

    PUSH also offer a bottom out 'bumper' as part of their tune that serves the same purpose. A few 575 riders have had the bumper installed with good results.

  3. #3
    DGC
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    Quote Originally Posted by kiwirider
    At 135x20x1.2mm you get a volume reduction of 3.24cc.

    You could do what I do and squirt in an extra 3/4 of a 5cc pillow pack of Fox Fluid into the air can and get the same result. Don't even have to remove the shock from the bike to get the fluid in. I've been doing this for about 18 months and have not experienced any problems with fluid migrating into the negative air chamber or blocking the bleed hole. Ramps up the last inch or so of travel nicely.

    PUSH also offer a bottom out 'bumper' as part of their tune that serves the same purpose. A few 575 riders have had the bumper installed with good results.
    Only problem with extra lube in there, is it will eventually come out, changing the amount of effect from when first put in, and it will make more of a mess especially when riding in warm weather. I had tried this a few years back with the dhx-a, it made a mess and I could feel a loss of progressiveness 2 weeks after the change, there was lube all over the shock shaft. A thick grease would be better than float fluid if you choose this route over the shim. Push is charging how much to tune your shock....and add the shim?
    OUCH...!!!!!!

  4. #4
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    i just read somewhere that the 2010 RP23 will include the Boost Valve technology to control bottoming better. Sounds like you will need to use the PP lever to turn it off and on though, which won't do much if you ride it wide open.

  5. #5
    DGC
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    2010

    Quote Originally Posted by unclekittykiller
    i just read somewhere that the 2010 RP23 will include the Boost Valve technology to control bottoming better. Sounds like you will need to use the PP lever to turn it off and on though, which won't do much if you ride it wide open.
    I heard the same, though I also heard the shock was not quite finalized, so we will see in a few months what comes of it.
    OUCH...!!!!!!

  6. #6
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    Thanks for that. I don't have a Sultan, but I do need to reduce the volume of a large can RS Monarch and I think that will do the trick.

    Apparently, RS makes "tuning bands" for the shock, but I have not found anyone who carries them.

  7. #7
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    Quote Originally Posted by DGC
    Only problem with extra lube in there, is it will eventually come out, changing the amount of effect from when first put in, and it will make more of a mess especially when riding in warm weather. I had tried this a few years back with the dhx-a, it made a mess and I could feel a loss of progressiveness 2 weeks after the change, there was lube all over the shock shaft. A thick grease would be better than float fluid if you choose this route over the shim. Push is charging how much to tune your shock....and add the shim?
    Haven't had this problem with the RP23. Nothing seems to migrate into the neg chamber and certainly not out and onto the shock shaft. How where your seals? Old I expect.

  8. #8
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    I just called Fox about the bottoming on my 09 5 Spot and asked about both the shim or adding fluid to the air chamber to solve it.
    They suggested I could make the compression more progressive by using a Fox standard size air sleeve(I guess the rp23 that comes stock with the 09 5 spot uses a larger sleeve).
    The sleeve and seal kit together were $40 and ordered it while I had them on the phone.
    I was directed to check their website under "tech & service" to find a air sleeve maintainence video so I can do it myself.

    Wanted to be sure I wouldn't void a warranty and thought Fox was helpful with their advice(although it cost more).

  9. #9
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    The LV (or "standard") air sleeve is a common fix for heavier riders and bottoming out problems. It's a very simple procedure - you also get a bit more plushness in the early part of the stroke since you run a lower initial air pressure than with the HV sleeve. It's more progressive at the end stroke due to the lower volume so your BO resistance goes up- a good combo all around, but basically the same idea as this ghetto option.
    When I see an adult on a bicycle, I do not despair for the future of the human race. ~H.G. Wells

  10. #10
    DGC
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    volume reduction

    Quote Originally Posted by Enel
    Thanks for that. I don't have a Sultan, but I do need to reduce the volume of a large can RS Monarch and I think that will do the trick.

    Apparently, RS makes "tuning bands" for the shock, but I have not found anyone who carries them.
    Your welcome.
    You can probably get a LBS to order you a shim for your RS shock. If not, they may be willing to send you one direct, call SRAM. Or better yet, I can make a call for you tomorrow.
    My original post shows you can do this shim mod to suit more than just a Turner or a Fox. I show specifics as it pertains to the 2009 DW 5 Spot and the RP23 that comes with it. I have been testing my shims in my shocks for the last 4 years or so. It is a very clean, easy and effective way to change the last bit of travel, or bottoming effect.....it works damn good.
    OUCH...!!!!!!

  11. #11
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    why not just run a coil over?

  12. #12
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    Quote Originally Posted by DGC
    The shim is made of ski base material, or better known as plastic. EXACTLY 1.2mm thick. I have tried thicker, around 1.5-1.7mm and it makes it nearly impossible to get the air sleeve back on.
    I have been considering this mod to my float. Rumor has it that fox doesn't make a low volume sleeve for the 8.5x2.5 version, so this type of fix is the only way to go. At any rate, you mention that it gets impossible to assemble with thicker plastic. Would you mind elaborating? Mechanical interference I would imagine, but does the plastic get knocked out as you assemble?

    Ever thought of using something softer? I was on McMaster and see you can get sheets of polyurethane in .060" (about1.5mm). Even if there was interference, with a bit of float fluid to aid, the rubber would deform and still slip on.
    http://www.mcmaster.com/#8824t125/=16mxmx
    Quote Originally Posted by saturnine
    that's the stupidest idea this side of pinkbike.

  13. #13
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    softer would be fine

    Quote Originally Posted by AL29er
    I have been considering this mod to my float. Rumor has it that fox doesn't make a low volume sleeve for the 8.5x2.5 version, so this type of fix is the only way to go. At any rate, you mention that it gets impossible to assemble with thicker plastic. Would you mind elaborating? Mechanical interference I would imagine, but does the plastic get knocked out as you assemble?

    Ever thought of using something softer? I was on McMaster and see you can get sheets of polyurethane in .060" (about1.5mm). Even if there was interference, with a bit of float fluid to aid, the rubber would deform and still slip on.
    http://www.mcmaster.com/#8824t125/=16mxmx
    Softer material would work fine, it is the thickness I speak of that would make it nearly impossible to get the sleeve back on. 1.2mm thickness works real well. I have tried in the 1.5-1.75mm thick and had to really push damn hard to get the sleeve back on. I would say 1.5mm thich as the max. Thing is at 1.2mm, you can always put in a wider shim. If it feels like too much boost at the end of the stroke, cut a few mm's at a time off and try it. The plastic does not get knocked out as you assemble with it being too thick, it just makes it almost impossible to get the sleeve back on. At 135mm in length the shim sits in the sleeve failry snug and almost clicks against itself as the ends meet.
    OUCH...!!!!!!

  14. #14
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    tried it

    I got a ride in last night with a shim like DGC shows. Amazing difference.
    This will probably work on all kinds of bikes and lengths of shocks for a couple bucks worth of plastic. I felt no difference in the first 3/4 travel and then it had the smoothest ramp up right at the end. At first I did not think it was working, with all the small bump mid stroke compliance still intact. This small bump mid stroke compliance is something that is super important to my riding, the dw-link has allowed for very light valving to be used so that the rear of the bike will absorb smaller bumps than anything I have done before and I don't want the mid stroke to be firmed up AT ALL. This mod just effects the very last bit of travel, at least in this size of shim. If someone bigger and faster than myself wanted more ramp up, they can either use a slightly thicker or slightly wider piece of plastic. It was so easy to install and with a sharp razor can be tuned perfectly. don't spend money on a small air can until you have tried a couple sizes of this. The small air can will radically alter your whole air spring, the shim in roughly the size DGC has created is an end travel adjuster.

    HDPE that can be had in sheets will work, but a cheap little trash can with thin walls from the Dollar Store works just as well, no shipping! I found that it was important to cut it the right length! If the strip is a little too short it will not 'pop' out tight and round on the inside wall of the XV sleeve which will make it grab the shock when I tried to slide the XV over the shock. If the sheet is a little thicker, make the strip a little narrower, simple.

    DT

  15. #15
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    So, this modification has always been curious to me as we've talked about offering something like this to our customers. I just happen to have one of these bikes here so I figured I'd check it out. Here are the results:

    The first graph shows the air spring curve comparison between stock and the DGC modification.
    The second graph shows the air spring curve comparison between stock and the PUSH bottoming system.

    Darren
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  16. #16
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    Quote Originally Posted by PUSHIND
    So, this modification has always been curious to me as we've talked about offering something like this to our customers. I just happen to have one of these bikes here so I figured I'd check it out. Here are the results:

    The first graph shows the air spring curve comparison between stock and the DGC modification.
    The second graph shows the air spring curve comparison between stock and the PUSH bottoming system.

    Darren
    Darren,

    Very interesting data, thanks for posting it!

    What are the two curves for each color? Is that hysteresis between the compression and rebound stroke or just different air pressures?

    Also, is the negative spring rate in the bottom set of curves at the beginning of the stroke or the inversion in the upper curves also at the beginning of the stroke a measure of the error bars on the graph? If not, how do you make sense of that behavior?

  17. #17
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    Darren, how about a third graph showing the difference between an LV can and an HV can, with no mods to either.
    So it seems to me to be, this thing that I think I see.

  18. #18
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    Darren, very cool. The push bottoming obviously does a better job at the end of stroke without messing with the rest of the curve. For a falling rate bike it looks like the DGC mod would be better since it has effect over the entire curve.
    Quote Originally Posted by saturnine
    that's the stupidest idea this side of pinkbike.

  19. #19
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    Darren, that's pretty cool, but what would be even more cool is if you would finish working on my RP3 and send it back to me.
    ****

  20. #20
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    What are the two curves for each color? Is that hysteresis between the compression and rebound stroke or just different air pressures?
    It shows both the compression and extension stroke....if you focus on the upper part of the line that's the actual force on compression.


    Darren, that's pretty cool, but what would be even more cool is if you would finish working on my RP3 and send it back to me.
    Doh! Fed Ex didn't have any service yesterday due to the weather so it'll be leaving today.

  21. #21
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    Quote Originally Posted by PUSHIND
    Doh! Fed Ex didn't have any service yesterday due to the weather so it'll be leaving today.
    That's what you said Tuesday!

    edit: he actually called me!
    Last edited by Renegade; 03-27-2009 at 02:55 PM.
    ****

  22. #22
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    That is interesting.

    You know, I would love to see a graph of the pushed rp23 on a TNT 5.5 spot for comparison. Purty please!

  23. #23
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    Quote Originally Posted by PUSHIND
    It shows both the compression and extension stroke....if you focus on the upper part of the line that's the actual force on compression.

    So the difference in compression and rebound at any point is fricition in an air shock?

  24. #24
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    The cylindrical plastic lid of a blank CD-R spindle works well for the mod. Not as soft a plastic as p-tex but...
    Someone else suggested it on one of DGC's threads and it works great.

  25. #25
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    quite interesting

    Quote Originally Posted by PUSHIND
    So, this modification has always been curious to me as we've talked about offering something like this to our customers. I just happen to have one of these bikes here so I figured I'd check it out. Here are the results:

    The first graph shows the air spring curve comparison between stock and the DGC modification.
    The second graph shows the air spring curve comparison between stock and the PUSH bottoming system.

    Darren
    Darren,
    As i see the graph's, my shim gets progressive on a more gradual curve, where your bottoming system allows a more linear feel longer then ramps up hard at the very end. Thank you for posting this, cool to see.
    Here is a picture of another shim I have used in the past on the dhx-a. I am testing a version of this currently on the DW, the shim is 135x17mm with the added raised end.
    Anyways, thanks again for posting these graph's.
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    OUCH...!!!!!!

  26. #26
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    Interesting mod, DGC...and quite innovative and inexpensive

    The PUSH mod looks great too. I wonder if a rider can tell if there is a difference. Of course, knowing my inability to use sharp tools and my ham-fisted nature, I'd have to go with Darren's mod by default.

  27. #27
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    Darren, any idea how an AVA sleeve compares to the previous curves?

    I called a bud and inquired about a LV sleeve for an 8.5x2.5 and he did confirm that they don't make it at Fox. But he did have an older RP3 with AVA he is going to let me play around with.
    Quote Originally Posted by saturnine
    that's the stupidest idea this side of pinkbike.

  28. #28
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    Darren,
    As i see the graph's, my shim gets progressive on a more gradual curve, where your bottoming system allows a more linear feel longer then ramps up hard at the very end. Thank you for posting this, cool to see.
    Here is a picture of another shim I have used in the past on the dhx-a. I am testing a version of this currently on the DW, the shim is 135x17mm with the added raised end.
    Anyways, thanks again for posting these graph's.
    Yeah, it was cool to measure the results. As you see, there's definitely merit to what you're doing.

    Interesting mod, DGC...and quite innovative and inexpensive

    The PUSH mod looks great too. I wonder if a rider can tell if there is a difference. Of course, knowing my inability to use sharp tools and my ham-fisted nature, I'd have to go with Darren's mod by default.
    The results are large enough that you would be able to feel the difference for sure.

    Darren, any idea how an AVA sleeve compares to the previous curves?

    I called a bud and inquired about a LV sleeve for an 8.5x2.5 and he did confirm that they don't make it at Fox. But he did have an older RP3 with AVA he is going to let me play around with.
    You know if I recall correctly, the AVA fully closed is just slightly larger than the current standard volume air canister. I'd have to double check that one.

    Anyway, I'm on my way to Fruita/Moab until Wednesday with my 5 Spot in tow....I'd love to stay and chat, but got some riding to do!

    Darren

  29. #29
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    Would the shim size be the same for a 7.5 x 2 shock on the V2 Sultan?

    It's freakin pouring here, and I need a good garage project.

    Thanks!
    Whining is not a strategy.

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    My Tiny Contribution

    For those of you who find suitable plastic shim material that isn't exactly 1.2 mm thick, here's a simple formula for figuring out the width of your shim, based on the thickness of your plastic material.

    Width (in millimeters) = 24 Divided by Thickness (in millimeters)

    So for the CD stack cover I found that is 0.9 mm thick, width is 24/0.9, or 26.7 mm.

    Since I'm not super agressive, and am working with a shorter shock, I'll probably just try 20 mm to start with anyway.
    Whining is not a strategy.

  31. #31
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    Quote Originally Posted by wormvine
    The cylindrical plastic lid of a blank CD-R spindle works well for the mod. Not as soft a plastic as p-tex but...
    Someone else suggested it on one of DGC's threads and it works great.
    That was a great tip. Thank you!

    First ride on the shimmed HV RP23. Still not as progressive as I'd like it. I'll try to cut a wider shim.

  32. #32
    DGC
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    custom shim for a custom ride

    Quote Originally Posted by nybike1971
    That was a great tip. Thank you!

    First ride on the shimmed HV RP23. Still not as progressive as I'd like it. I'll try to cut a wider shim.
    That is the whole idea with the shims, make the size you want based on your riding. As you use bigger shims though you might start to feel a little loss of mid stroke plushness, but a few more mm's should be fine. Play with it and find out what works for you. I don't like the feel of air shocks when they are too linear long and deep in the travel then ramp up real hard, feels too punchy to me. But, that is me. Different strokes for different folks. That is the problem I had with the dhx-a on the TNT bike.
    The CD spindle idea shows what I said recently, there is all kinds of plastic out there if you think of it. The next one I am trying is a 1.5mm thick not as wide with a ramp on the end like I pictured above last night. It might get too much like the punchy feel I don't like, we'll see.
    Glad to see your trying this shim mod.
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    OUCH...!!!!!!

  33. #33
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    Quote Originally Posted by DGC
    That is the whole idea with the shims, make the size you want based on your riding. As you use bigger shims though you might start to feel a little loss of mid stroke plushness, but a few more mm's should be fine. Play with it and find out what works for you. I don't like the feel of air shocks when they are too linear long and deep in the travel then ramp up real hard, feels too punchy to me. But, that is me. Different strokes for different folks. That is the problem I had with the dhx-a on the TNT bike.
    The CD spindle idea shows what I said recently, there is all kinds of plastic out there if you think of it. The next one I am trying is a 1.5mm thick not as wide with a ramp on the end like I pictured above last night. It might get too much like the punchy feel I don't like, we'll see.
    Glad to see your trying this shim mod.
    DGC,

    I should have said this explicitly. That's a brilliant mod because it is so simple and so easy to customize. So, thanks!

    Could you explain the "ramp" at the end of the shim in the picture? I am not sure I understand it.

  34. #34
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    ramp

    Quote Originally Posted by nybike1971
    DGC,

    I should have said this explicitly. That's a brilliant mod because it is so simple and so easy to customize. So, thanks!

    Could you explain the "ramp" at the end of the shim in the picture? I am not sure I understand it.
    First off, your welcome. It can be installed in a minute or 2, very easy to do as you said, more people in here should give it a try.
    The ramp is for a pocket in the air sleeve. On the inside of the air sleeve there is a slightly machined 1/4 inch long pocket, it is very slight in depth. If there is a decent amount of lube in the air sleeve you wont even see the depression it is so slight. My feeling is if you fill that pocket entirely with a tight fit, you will get a slightly more progressive feel at the very end of the stroke. More bottomout protection. I have used black electrical tape, and layered it to get the effect i want. Now I am trying to make that 1/4 end ramp with pitex or something more solid.
    The picture shows i believe 2 layers of tape. I have before on the dhx-a crammed as many as 5 layers in there before, but that makes it real hard to get the sleeve back on the main air body.
    OUCH...!!!!!!

  35. #35
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    Rs

    Quote Originally Posted by Enel
    Thanks for that. I don't have a Sultan, but I do need to reduce the volume of a large can RS Monarch and I think that will do the trick.

    Apparently, RS makes "tuning bands" for the shock, but I have not found anyone who carries them.
    I called SRAM, 2 different people acted as if they never have heard of shims in an air sleeve before. Both denied RS making them. I have talked with someone outside SRAM who says they do have them and has seen them. Probably has not made it to the consumer end of the market yet, maybe it exists in the race department. I would bet they will have a few in a drawer at Sea Otter. If your Monarch has the external HV sleeve then make one as I have done here for the Fox.
    OUCH...!!!!!!

  36. #36
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    Quote Originally Posted by DGC
    I called SRAM, 2 different people acted as if they never have heard of shims in an air sleeve before. Both denied RS making them. I have talked with someone outside SRAM who says they do have them and has seen them. Probably has not made it to the consumer end of the market yet, maybe it exists in the race department. I would bet they will have a few in a drawer at Sea Otter. If your Monarch has the external HV sleeve then make one as I have done here for the Fox.
    Thanks for checking into that for me. That is pretty much the same response I got to inquiries. I have a pretty reliable source that says they exist.

    The Monarch is built a little different from the Fox. Here is a pictorial of it being taken apart.

    First let all the air out.

    <a href="http://picasaweb.google.com/lh/photo/Vrs2SdGjMW5j9X2FOHsvhg?feat=embedwebsite"><img src="http://lh4.ggpht.com/_krWgAPsu4g0/SdACiOUv4KI/AAAAAAAAGQ4/0quPJnnIMTs/s800/IMG_0926.JPG" /></a>

    Take off the O-ring at the bottom.

    <a href="http://picasaweb.google.com/lh/photo/_KoP8PlCQEm9rqBMev54Mw?feat=embedwebsite"><img src="http://lh4.ggpht.com/_krWgAPsu4g0/SdACjK67mUI/AAAAAAAAGRA/1UjgMSgnZRk/s800/IMG_0927.JPG" /></a>

    Slide the sleeve off.

    <a href="http://picasaweb.google.com/lh/photo/hzC57o6Ba2PiIDYYpvUQ6Q?feat=embedwebsite"><img src="http://lh4.ggpht.com/_krWgAPsu4g0/SdACkMIrYTI/AAAAAAAAGRI/is9g4VXbn7Q/s800/IMG_0928.JPG" /></a>

    <a href="http://picasaweb.google.com/lh/photo/_YpPOXmmD3rPlgsy0rhPJw?feat=embedwebsite"><img src="http://lh6.ggpht.com/_krWgAPsu4g0/SdACk3KS8zI/AAAAAAAAGRQ/gx5ECM-_Zt8/s800/IMG_0929.JPG" /></a>

    As you can see, the sleeve does not have the lip in it like the Fox. The lip is on the shock body. In some ways, this makes it easier to adjust the air volume with just some rubber bands.

    <a href="http://picasaweb.google.com/lh/photo/juSiaaWo1cfRDxqhjl9I1g?feat=embedwebsite"><img src="http://lh3.ggpht.com/_krWgAPsu4g0/SdAClyoHuFI/AAAAAAAAGRY/UgB_DrGQYYo/s800/IMG_0930.JPG" /></a>

    My shock was way, way too linear for my bike. Bottomed easily with correct sag. I added two layers of cut inner tube and a rubber band from some Broccolli. Ramps up nicely now. Seems a little less progressive than the small volume Fox currently on the bike. I suppose you could just as well wrap it with some tape.

    I actually prefer the small volume Fox RP23 as far as the spring goes, and it requires no fussing. Nice to have the option to tune the spring though. No trail time on the RS with the more progressive spring yet.

  37. #37
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    Quote Originally Posted by PUSHIND
    You know if I recall correctly, the AVA fully closed is just slightly larger than the current standard volume air canister. I'd have to double check that one.

    Anyway, I'm on my way to Fruita/Moab until Wednesday with my 5 Spot in tow....I'd love to stay and chat, but got some riding to do!

    Darren
    Riding is overrated, just hang here and BS about our shocks instead

    Interesting on the AVA. I will give it a try regardless. If it doesn't do the trick then I will check out this shim deal.
    Quote Originally Posted by saturnine
    that's the stupidest idea this side of pinkbike.

  38. #38
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    would be interesting if Darren or DT commented on the upcoming boost valve version of the RP23:


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    I tried the mod on my Sultan. Very easy to do with DGC's instructions. Thanks.

    It worked fine, but I don't really think the Sultan needs it, maybe because of its lower leverage ratio compared to the Spot.

    I used a shim about 75% the volume of DGC's (135 x 20 x 0.9), and with 15 mm of sag, I no longer used full travel on a rough, technical ride where I normally gently feel bottom once or twice. If I were doing a lot of drops, I would slip that shim right back in.

    I need a shim that will make my March legs feel like they do in July!

    Thanks again, DGC!
    Whining is not a strategy.

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    Quote Originally Posted by PUSHIND
    So, this modification has always been curious to me as we've talked about offering something like this to our customers. I just happen to have one of these bikes here so I figured I'd check it out. Here are the results:

    The first graph shows the air spring curve comparison between stock and the DGC modification.
    The second graph shows the air spring curve comparison between stock and the PUSH bottoming system.

    Darren
    Hey Darren,
    I have the PUSH bottoming system on my Mojo (w/std air can). So does my shock have the same curve as you've shown? I have felt that it was too big of a change from the stock shock, i.e., it prevents bottoming too much such that I never use the last 8mm of shock travel, even on the biggest drops that I do.

  41. #41
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    Quote Originally Posted by MB24
    Hey Darren,
    I have the PUSH bottoming system on my Mojo (w/std air can). So does my shock have the same curve as you've shown? I have felt that it was too big of a change from the stock shock, i.e., it prevents bottoming too much such that I never use the last 8mm of shock travel, even on the biggest drops that I do.
    Darren, similar situation for me too. I've gotten a few rides in on the RP3 since you reworked it; I have the HV can with the P-bottoming system. The last 1/2 inch of shock stroke is unobtainable. What exactly is the Push bottoming system? Do you guys put a stiff elastomer in there?
    ****

  42. #42
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    The bottoming system that's installed in your shocks only effects the last 1/4"(6.35mm) of travel, so in both of your cases the bottoming system is a factor. Are you measuring the distance between the wiper and travel indicator o-ring to get your measurements? Unlike the SPOT, the MOJO is very linear in nature so it's uncommon to not get full travel. With the SPOT, it's mechanical nature is such that you get a lot of bottoming protection from the linkage so the bumper that is used is much softer.

    Darren

  43. #43
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    Darren, yes, I'm measuring from the wiper to the o-ring. The travel feels slightly linear untill the shock has compressed 1.5 inches, then it sofly but surely hits that wall. It lfeels just like your graph looks, but skewed.
    ****

  44. #44
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    Funny how it's a modification. I thought the large air volume was a mod from this to a more linear response. People used to complain about the increasing rate of air shocks. Now it's the other way around.

    That PushInd curve looks very sweet though. Kinda like a soft bottoming feature..IE like the rubber bumper on a coil shock.
    Last edited by lidarman; 04-08-2009 at 05:17 PM.

  45. #45
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    Quote Originally Posted by PUSHIND
    The bottoming system that's installed in your shocks only effects the last 1/4"(6.35mm) of travel, so in both of your cases the bottoming system is a factor. Are you measuring the distance between the wiper and travel indicator o-ring to get your measurements? Unlike the SPOT, the MOJO is very linear in nature so it's uncommon to not get full travel. With the SPOT, it's mechanical nature is such that you get a lot of bottoming protection from the linkage so the bumper that is used is much softer.

    Darren
    Yes, measuring from the wiper lip to the 0-ring, I can use only 43mm on the bigger drops. It does feel like your graph. Before the bottoming system was installed, I would bottom the shock a bit too often.

    >Mojo, Pushed RP23 w/std air can

  46. #46
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    Wow, this is such a huge resource of information.... one question though... how do I do this on a standard PR23 that I am constendly bottoming out when I run the recomended 15mm sag on my Mojo... I need the Boost at the end of the stroke thing...
    I weight about 86kg.

    Thanks

  47. #47
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    It's tough to diagnose over the internet. I would say for Renegade and MB to just shoot my an email or call so we can discuss it further....or in Renegade's case just swing up with your bike!

    That PushInd curve looks very sweet though. Kinda like a soft bottoming feature..IE like the rubber bumper on a coil shock.
    That's a big part of it...see photo.

    Darren
    Attached Images Attached Images

  48. #48
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    Darren

    Can the guys at TF-Tuned do the bottom out thing for me?

    I will be sending my Rp23 over that way at the end of the month... is there anything specific I should ask for to get teh best performance fof my mojo?

  49. #49
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    Great discussion going on here. Any experience with DT-Swiss shock? I'm on the Mojo and do aggressive riding. There are no HV sleeve to take out, but injecting grease into Air chamber may work.
    Anyone tried this?
    I used to run tubes like you are, but then I got thorn in my wheel.

  50. #50
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    Great idea DGC like others have said quite cool, Iíve gone with the CD lid plastic setup, and went a little wider 25mm vs 20mm since Iím heavier and a little out of shape at mo but gym will get me back there hopefully In few months, one of reasons Iím playing with my air shock, Iíd rather be running a coil Avy etc, [no new bike stuff till working again] I do have a Romic which is working out surprisingly well but thought this would be fun to try, since its lying around.
    <o></o>
    Iím using a DHXa, and it was slightly in stuck down mode which was weird because it did extend and function properly on the bike, but was slightly shorter in stroke than it should have been, because it worked fine I thought it must have been swapped for wrong stroke in the beginning as mine was a warranty replacement for being stuck down since new! But no some air must have gotten in the negative chamber, either that or the grit and crap that had built up in there had been the issue as there was some crap in there not much but ya only need a little!
    <o></o>
    So for the outer can 25mm width by 135 in length was perfect fit and I got the can fitted again no probs!
    <o></o>
    Like you say itís very simple to do, so easy everyone should try it, nothing can go wrong, just follow the above, basically the same as the ownerís manual anyways.
    <o></o>
    So I definitely feel a difference in initial stroke and then some nice ramp up, it does feel more progressive, Iíve not set my normal air setting so I could still cycle the shock through enough of its travel to get a feel in static mode, nice definite difference, still need to do a proper ride though to prove the setting and shim is right Iíll make some smaller and wider now and see over time how much difference they make, be nice to get rid of that crap mid stroke run a little less in the main chamber for smoother initial bump feel and more sag but with ramp up at end without over doing the bottom out adj on the bor knob or extra psi in the piggy back!
    <o></o>
    So will report over some time, my wee get back on the bike loop has a bit of everything itís a perfect test loop, berms roots lots of downs and climbs too 2ft drops lol whoops, Iím not up to jumping at normal riding so true bottom out ramp up will be some time off yet, but I was getting full travel on this trail with 220psi in the man chamber previously so I had to ramp up the bottom out resistance knob, so be interesting if I can use less air in the main and dial back the bor on the piggyback with the shim mod in there!
    Last edited by trailadvent; 04-14-2009 at 11:02 PM.
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