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  1. #1
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    Anyone else had their pivots stiffen up?

    I was a bit disconcerted to find that the pivots on my XCE need a lot of effort to rotate, so I took the main one (BB) apart to inspect. There didn't appear to be any contamination (as I had initially feared), but the pivot shaft was almost stuck in the bushings, taking one out with it when I finally punched it out. I called Turner and to their credit they were very responsive and are sending me a new bushing/shaft set.
    The rest of the pivots turn a bit easier; none are "notched" or "crunchy", but still very "tight". The bike is very much broken in, all the pivots have been regularly greased, and the bike is only a year old. If anything I would expect the bushings to get looser as they wear, not tighter.
    This leaves me wondering how stiff the pivots should be, and how this effects the suspension. I had imagined that a suspension pivot would turn with approximately the same effort as a headset, but even the looser ones on my XCE are significantly tighter than that. It seems you would want the pivots on a FS bike to be as smooth as possible to maximize the effectivness of the rear suspension. Anyone have any thoughts/experience in this matter?

  2. #2
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    Good lord, I'll buy those pivot shafts off you. PM me. I'll take them.

    No, what you report is not the way the system is supposed to be. Barny's are what I would call perfect. Very snug, smooth, well dampened. Like a King headset packed with high viscosity grease, as you described. My XCE's main pivot is looser than that. It spins fairly freely. It is smooth and very even, but does not have that dampened feel. My other pivots are more or less like Barny's. My Spot is like my XCE: the main feels looser, the others "correct". Turner says their main pivot shafts are the same specs as the others, yet they also seem to recognize that the main pivots tend to run a bit loose for unexplained reasons. Perhaps they are 0.001-0.002" larger in diameter or something. Anyway, I like to find a "fat" shaft to run in the main pivot. If you want to unload your sticky ones, email me.

    BTW- did you ever get grease to cycle through your pivots, or were they dry looking with dry, dark smudges on the bushings when you took them apart? I think sometimes if you don't get a good coat of grease on them from the get go, they don't spread the lube evenly later.

    Good luck.
    My video techniques can be found in this thread.

  3. #3
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    Torque numbers

    Quote Originally Posted by miles e
    It seems you would want the pivots on a FS bike to be as smooth as possible to maximize the effectivness of the rear suspension. Anyone have any thoughts/experience in this matter?
    To quantify this is going to hard. The only way is to measure the torque that it takes to move the linkage (maybe one can use a torque wrench to do so).

    Having said that, intuitively a pivot should be at least as smooth as a headset. Something you can move with a finger with no effort given a lever of about 12". If you need to apply a lot of torque to move the pivot (headset) something is obviously wrong, as Turner-service told you.

    My pivots are "smooth" right now, whatever that means it takes little effoert to move them, my AMP pivots where similarly smooth, and so where the bushings of my GT and the bearings pivots fo the same GT. Something must have gone wrong with yours, maybe something as simple as dried up grease? On my right main pivot the o-ring is slightly out of allignment, a little "amount" of the o-ring is sticking out, probably due to a small error in assembling the at the factory (sigh) . Maybe a mis-assembled o-ring is the culprit in your case? it is unlikely that it would add much friction to the pivot but it is worth checking out.

    (In my case it seems to be causing some loss of grease from the right side, but I am not sure it might be normal to have a small amount of grease coming out after breakin in the bushings ...).

    PS a suggestion: sell the messed up pivots to the Turner-fanatic.
    Last edited by Davide; 05-03-2004 at 11:59 PM.

  4. #4
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    There was grease everywhere inside the pivots and coming out the seals, so I don't think that was the issue. Neither the bushing that came out nor the shaft showed any detectable wear (amazing considering how much friction there is between the two when installed), and the shaft rotated easily enough in the bushing when both were removed from the bike.

    I was able to push the bushing back in by hand (Turner said this was a good indication that the pivot shell was not the culprit), but I had to punch the shaft back in with a rubber mallet. I just can't imagine something that fits that tight can rotate freely enough to provide "active" suspension. I know the bushings run a bit stiffer than bearings (this can be good too I'm sure), but it seems like way too much on my XCE. My wife's XCE moves noticably more freely, and the brand new RFX frame is just a bit stiffer than that- I imagine it would be about the same as my wife's XCE once broken in.

    I guess my main questions are:
    -Should the pivot shaft be able to go in and out by hand?
    -Has anyone else had this problem develop over time, or is it just the fact that my pivot shaft outside diamter and/or bushing inner diameter were likely out of spec from day one?
    -Assuming a normal amount of "damping" from the bushings, how much less active is a Turner than a similar bearing equipped bike? I realize this is an apples to oranges question, but for a minute I was seriously considering going to a bearing equipped bike to achieve a more supple and active suspension (Now I'm going to wait to see if the new shaft and bushings help smooth things out).

  5. #5
    No, that's not phonetic
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    Quote Originally Posted by miles e
    -Should the pivot shaft be able to go in and out by hand?
    No. I usually have to insert a 6mm allen into the pivot to engage the wrench flats inside the shaft and using a twisting movement I can break the shaft free and push or pull the shaft through. If you can get a shaft out or in using just moderate finger pressure, that sounds quite loose to me. Too loose. I have had to punch the Horst links out with a tool. Those suckers can be snug.

    Quote Originally Posted by miles e
    -Has anyone else had this problem develop over time, or is it just the fact that my pivot shaft outside diamter and/or bushing inner diameter were likely out of spec from day one?
    It is possible that the Igus bushings are out of spec and too small. They should engage the frame more tightly than the shafts, that way the shaft spins in the bushing and the bushing does not spin in the frame. That would honestly be my only concern. All the parts in the pivot are inert to water and grease so would not "swell". They must have been that way from the get-go. A pivot could stiffen if it were ridden totally dry, but that is the only scenario where I think that would occur.

    Quote Originally Posted by miles e
    -Assuming a normal amount of "damping" from the bushings, how much less active is a Turner than a similar bearing equipped bike?
    On yours, the stiction could become noticeable. With the shock removed and the rear end assembled, how much force does it take to move the rear end up and down? It should not necessarily sag under its own weight (no rear wheel), but it should move with gentle pressure. I would say it takes at most 1/2 a pound of force at the dropout to move the suspension. I weigh 195 with all my junk. When I ride over a bump I am applying hundreds of pounds of force to the rear end. I think that may give you an idea of how large the normal pivot "stiction" force is compared to the other forces: many orders of magnitude smaller. I really don't think even the Princess and the Pea could tell the diff between a bushing and a bearing. Add to that a platform shock which will contribute far more resistance to movement than the bushings ever could.

    An interesting experiment for you may be to rent/demo a bearing equipped 4-bar for a day and see if you can feel a difference.

    I head out for my summer field season in a week. Let me know if you don't want the old shafts. I could horse-trade you a derailleur hanger or something....
    My video techniques can be found in this thread.

  6. #6
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    Quote Originally Posted by tscheezy
    I have had to punch the Horst links out with a tool. Those suckers can be snug.
    Mine were so snug I needed to press them in. I plan on checking them out one day this week. See if they've loosened any.

    Quote Originally Posted by tscheezy
    I head out for my summer field season in a week. Let me know if you don't want the old shafts. I could horse-trade you a derailleur hanger or something....
    By the way, the derailleur hanger that you so kindly donated to me for my Saint experiment showed up yesterday. Thanks a ton.

  7. #7
    No, that's not phonetic
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    No problems, man. Turner sent me something like 5 spares as part of my "payment" for doing the maintenance site. I would need to crash a lot more to chew through all of those, so I figured I'd spread the wealth.

    Let us know how the Saint thing works out.
    My video techniques can be found in this thread.

  8. #8
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    Thanks for the help T. I could get the bushing into the frame infinitely more easily than the shaft into the bushing, so I hope it isn't the case that the bushing is spinning and not the shaft when the pivot moves. To clarify, how exactly do you "break the shaft free" with the allen key? Isn't it already "floating" inside the bushing? I don't see how an allen key could apply lateral force (moving it left or right out of the frame) to it, or how spinning it radially should free anything up that doesn't already pivot freely. Are you saying you just use the allen to twist the shaft radially as you apply lateral force with your hands?

    I'll update when I have the new shaft & bushings installed. If it looks like the shaft is indeed oversized it's all yours- go ahead and PM me your address and I'll get it out if that's the case. You're probably right about the force it takes to overcome the bushing's resistance being inconsequential relative to the forces being applied to the rear suspension, but I might try out a bearing equipped bike if I still have doubts after replacing the pivot.

    My main concern was that the pivot just wasn't holding up; assuming it started out good and went to bad, it could certainly go from bad to worse. However, it sounds like it just started off bad and stayed that way, so now I have little doubt that if I can get it to be "good" it will stay that way too.

  9. #9
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    Quote Originally Posted by miles e
    Are you saying you just use the allen to twist the shaft radially as you apply lateral force with your hands?
    Precisely. When the shaft is sitting statically in the bushings, it takes a little jab to get it moving. The easiest way is to use the allen to twist the shaft, and as soon as it is slipping in rotation, you can push it through laterally with much greater ease. As long as you are going at it sort of slowly, the 6mm allen will "hold" in the wrench flats with enough friction that you can spin the shaft quite a ways out just by continuously spinning it, with mild pushing pressure. Once you have enough exposed to grab it with your fingers or a rag, continue twisting (rocking back and forth) and pull with your hand also. The reason the Horsts are hard to get out is because they don't have allen flats to grab and break/spin them free.

    I do agree that it is worrisome that the bushings show a greater affinity for the shaft than for the frame. Look inside the frame's pivot shell and see if you can see obvious rub marks where the bushing was moving relative to the frame. In the end, if the new bushings go into the frame snugly and the new shafts go into the bushings using the same allen-twisting motion you used to get them out (not having to pound them), I think you are set.
    My video techniques can be found in this thread.

  10. #10
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    Quote Originally Posted by tscheezy
    Precisely. When the shaft is sitting statically in the bushings, it takes a little jab to get it moving. The easiest way is to use the allen to twist the shaft, and as soon as it is slipping in rotation, you can push it through laterally with much greater ease. As long as you are going at it sort of slowly, the 6mm allen will "hold" in the wrench flats with enough friction that you can spin the shaft quite a ways out just by continuously spinning it, with mild pushing pressure. Once you have enough exposed to grab it with your fingers or a rag, continue twisting (rocking back and forth) and pull with your hand also. The reason the Horsts are hard to get out is because they don't have allen flats to grab and break/spin them free.

    I do agree that it is worrisome that the bushings show a greater affinity for the shaft than for the frame. Look inside the frame's pivot shell and see if you can see obvious rub marks where the bushing was moving relative to the frame. In the end, if the new bushings go into the frame snugly and the new shafts go into the bushings using the same allen-twisting motion you used to get them out (not having to pound them), I think you are set.
    I've always wondered why Turner doesn't use loctite to keep the bushings from rotating in the frame. It seems to me that a little bit of loctite would ensure that the bushing is always fixed.

    What do you think? I know that I have to loctite my fuel bushings into the frame. It just seems to me that loctite would remove the "fear" of the bushing miving in the frame....causing wear.

  11. #11
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    I personally cannot see any reason why you could not use some loctite. I think I would use something with a lower hold strength than blue though. What did you use on your Trek?

    Assuming the bits in the pivot are the correct spec, I don't think the loctite is necessary since the bushings go in dry, and the shaft is greased. But if it offered peace of mind, I guess that is a reasonable reason to do it.
    My video techniques can be found in this thread.

  12. #12
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    Quote Originally Posted by miles e
    I was a bit disconcerted to find that the pivots on my XCE need a lot of effort to rotate, so I took the main one (BB) apart to inspect. There didn't appear to be any contamination (as I had initially feared), but the pivot shaft was almost stuck in the bushings, taking one out with it when I finally punched it out. I called Turner and to their credit they were very responsive and are sending me a new bushing/shaft set.
    The rest of the pivots turn a bit easier; none are "notched" or "crunchy", but still very "tight". The bike is very much broken in, all the pivots have been regularly greased, and the bike is only a year old. If anything I would expect the bushings to get looser as they wear, not tighter.
    This leaves me wondering how stiff the pivots should be, and how this effects the suspension. I had imagined that a suspension pivot would turn with approximately the same effort as a headset, but even the looser ones on my XCE are significantly tighter than that. It seems you would want the pivots on a FS bike to be as smooth as possible to maximize the effectivness of the rear suspension. Anyone have any thoughts/experience in this matter?

    Have not had my 5 long enough for that to happen, BUT one of the rear pivots did come very loose with in the first week and a half of getting the bike, and only 2 rides on, checked the torque on both pivots, - one side was over 40lbs and the loose side was like 10lbs - both are now set at 20lbs, even though the paper work that my freind has says they should be about 9-12lbs... shot a little bit of grease in all pivots.. and it is just fine now

  13. #13
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    Quote Originally Posted by tscheezy
    I personally cannot see any reason why you could not use some loctite. I think I would use something with a lower hold strength than blue though. What did you use on your Trek?

    Assuming the bits in the pivot are the correct spec, I don't think the loctite is necessary since the bushings go in dry, and the shaft is greased. But if it offered peace of mind, I guess that is a reasonable reason to do it.
    Trek recommends Loktite 290 if the bushing is a good fit (somewhat tight) in the frame or RC680 if there are any gaps.

    It just makes sense to me. I may use loktite when I eventually service the bushings. I don't believe that the loktite will damage the bushings....and I know it won't damage the frame.

  14. #14
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    Quote Originally Posted by gritsngravy
    checked the torque on both pivots, - one side was over 40lbs and the loose side was like 10lbs
    When you checked the torque, did you check to see what force was needed to break the bolts free? If that was the case, you were measuring the thread locker's holding force (which seems excessive to me- the "green" they use is awfully strong) not the actual bolt torque. There really is no way to know the original torque when disassembling a bolt held with thread locker.

    Turner does recommend you check ALL bolt torques before EVERY ride. That's the lawyers talking.
    My video techniques can be found in this thread.

  15. #15
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    Quote Originally Posted by WarrGuru
    Trek recommends Loktite 290 if the bushing is a good fit (somewhat tight) in the frame or RC680 if there are any gaps.
    The shear strength of the 680 is 4,000psi. Can you get the bushing out again later? I guess it may not "grab" the Derlin or Teflon of the bushing very well. They obviously have piles of compounds. For instance, the 641 is described as "A controlled strength retaining compound that is ideal for cylindrical parts that require disassembly. Recommended for maximum diameter clearance of 0.008"."
    My video techniques can be found in this thread.

  16. #16
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    I had posted this in another thread, sounds like it fits here also.

    My SO has been trying to gain plushness on her burner, she's been questioning her propedal float, and bushings/pivot break in (she's coming off a bearing/fsr).
    When I was switching out the rockers(first ever disassembly) I really struggled with the pivot bolts, either that green thread lock is extra solid or the bolts had gotten some extra torque.
    Greased the pivots and reinstalled, torqued, and now she feels the bike is much plusher and she's liking the propedal more.
    Hard to tell what the torque was before with the threadlock factor, but that was an interesting experience and goes to show that suspension tuning goes beyond shock performance.

  17. #17
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    Quote Originally Posted by tscheezy
    The shear strength of the 680 is 4,000psi. Can you get the bushing out again later? I guess it may not "grab" the Derlin or Teflon of the bushing very well. They obviously have piles of compounds. For instance, the 641 is described as "A controlled strength retaining compound that is ideal for cylindrical parts that require disassembly. Recommended for maximum diameter clearance of 0.008"."
    I've now checked both the instructions for changing Sugar bushings and Fuel bushings. The wording is slightly different, but they recommend the same Loctite adhesives.

    290 is the adhesive used for almost all bushing installations. The RC680 is to be used ONLY when the bushings fit loosly into the frame. My guess is that the extra strength is needed when the gaps in the frame need to be filled....so the loctite 680 would need to handle significant loads in addition to holding the bushing in place..

    In the case of Turner pivots, I'd only use the 290. I may just do that. I can't see where it could hurt, but I can make a case for the opposite. Not using loctite could result in frame damage if the bushing turns in the frame.

  18. #18
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    I called Turner a few weeks ago to explain my dilemma and three days later they had a new set of pivot shafts, bushings, and pivot bolts to me- great service! Turns out it was the original bushings that were causing the additional friction- I put the new bushings in with the old pivot shafts and itís like butter. Iím sure the bushings must have been like this from the beginning, as they would develop play if they were worn, rather than tightening up. Perhaps the additional friction in these bushings was indistinguishable from the inherent friction of new bushings if/when the frame went through QC.

    Between racing my 29er, wet trails, and the bushing saga the XCE had been out of commission for a couple months, so I was very eager to get it back together and get back on it. I think the suspension is even a bit smoother yet with the new bushings, but Iíd been on my hardtail so long it was impossible to tell for certain. At any rate I was wooed all over again by the Turner ride. I also ran my seatpost a couple inches lower than normal (Iím 6í on a medium frame), which gave the bike a more balanced feel, even if I wasnít getting proper leg extension.

    With a renewed appreciation for the Turner ride and bushing system (remarkably there was no hint of contamination in the pivots after almost a year), and the realization that my XCE is a bit too small I have finally decided to build up my RFX frame. It is a large, which should fit me a bit better, and be more bike than Iíll ever need. You can find XCEís pretty regularly in the classifieds now, so I probably wonít even bother to post a link here when mine goes up in a week or two. I will post some pictures of the RFX when it gets put together though, as it seems to have quite the following. If all goes as planned Iíll even have a little surpriseÖ

  19. #19
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    Quote Originally Posted by miles e
    ...I will post some pictures of the RFX when it gets put together though, as it seems to have quite the following. If all goes as planned Iíll even have a little surpriseÖ
    ...oh, I know! You're going to give it to some other mtbr.turnerforum rat. How generous of you.

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