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  1. #1
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    Modifying U-turn Travel?

    I was wondering if it is possible to modify the travel of a Pike from the stock 95-140mm to lets say 65-110mm and have the u-turn and other adjustments still work? Where would one get the fork serviced like this, if even possible? I am looking for a very short travel fork for doing mainly trials with and some urban. Thanks

  2. #2
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    XSL_Will mentions unwinding the spring where it stops on the adjustment to let you wind it down farther. It looks do-able.

  3. #3
    Meh.
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    It is possible, but it's super time consuming. You have to uniformly heat the spring and spread out the bunched spring in the middle. This bunched section is what prevents the spring from winding down into the u-turn plate any further. If you're interested, I have a spare medium spring that I can start on. I've only done one so far. It increased his max travel too. But as I said, it's super time consuming.

    The travel is pretty much 0-160mm after I'm done. I duno, I wasn't real happy with the other one I did. It did what it was supposed to do, but something felt off to me. The owner was ecstatic though.

  4. #4
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    I think that'd be sweet to have.

  5. #5
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    heating the spring, does it become softer in terms of springrate?

    as springs are specially tempered, thats why they are so...springy?

    i know heat + automotive springs causes bad mojo.

    but this is interesting none the less. Take pictures for a DIY/how to next time around?

  6. #6
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    Well, at 160mm it'd be softer, and then at say 20mm, it'd be much stiffer.

  7. #7
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    granted, but comparatively speaking, 20mm may be as soft as OEM 85mm at that point. Heat can do crazy things to springs

  8. #8
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    stealin the glory for my ideas will? didnt i explain to you how to do it when i did it for jj?

  9. #9
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    oh yeah, to clearify about the spring rate changing. it wouldnt make that big of a differnce, the area that you are stretching out on the spring is the last couple inches of the spring. youd be then turning the plastic ...guide thing that actually adjusts the height of the fork in to that area that you un wound. very little, if any, of that unwound/heated and cooled spring would be compressed ever. so no the spring rate and stiffness would not realy be affected presuming you only fvcked with that small area of spring, and only heated it as you needed to.

    another way of accomplishing the same thing is to just cut off that compressed bit of coil. you loose the upper end of you travel (max travel would be roughly 90-95mm) but you'd eliminate any concern for messing up the spring rate or spending two hours with an acetaline torch.

    i'm kinda lost as to what psyber optix and stab rider are talking about. if your talking about the differnce in spring stiffness when your fork is at 160mm vs when its at 20mm there is no differnce. in u-turn forks there is a rod that bolts to the bottom of the lowers. then at the top of the rod there is a "threaded" plastic peice taht sits inside of the spring. the spring is then connected to the top cap that you turn ot adjsut your travel. so as you turn you "wind down" yoru travel you are actually winding your fork down. you turn the spring around the plasic piece that pulls the crowns and everything down. i'l try to find some pictures that explain that all better. but essentialy the bottom of the spring never touches anything, the spring is braced against that plastic peice so no matter where in the travel it is it will give the same stiffness. where thats a good thing or not is up to you. hope that explains everythig. i'll try to explain it again later if anyone needs....

  10. #10
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    actually it makes sence, i was thinking preload adjustment but didnt realize that it was just adjusting the position the spring holds in terms of travel.

    thanks for clarrifying


    ...i learn something new every day

    but pictures would still be cool to see.


    Off Topic: i worry my fork may be damaged as there is a good amount of oil coming up by the seals that seem to collect a whole bunch of dust. is this normal, or is there a seal busted internally somewhere? it keeps making rings of grime deposites on the stanchions.

  11. #11
    Just Ride
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    here ya go this kinda explains the spring alittle more
    Attached Images Attached Images

  12. #12
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    Quote Originally Posted by zerossix
    stealin the glory for my ideas will? didnt i explain to you how to do it when i did it for jj?
    When did you do it for JJ? You never told me about it. To be honest, I did get the idea from somebody else, but I don't think it was you.

    The first (and only) one I did was many a month ago.

    Heating it can change the physical properties of the spring. I cannot guarantee it. If it fails, I will not be held liable or accountable for it.

  13. #13
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    Quote Originally Posted by XSL_WiLL
    When did you do it for JJ? You never told me about it. To be honest, I did get the idea from somebody else, but I don't think it was you.

    The first (and only) one I did was many a month ago.

    Heating it can change the physical properties of the spring. I cannot guarantee it. If it fails, I will not be held liable or accountable for it.

    i'm pretty sure i told you about it a while ago. i was playin around wiht it for jj. i made one for him and everything he never ended up using it or anything i still have it. it was definitley many months ago.

  14. #14
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    Nice pic and info, thanks!

  15. #15
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    what has to be done to the spring exactly?(diagram would do) and for what reasons?

    the reason i ask is im wonderin if would it be possible to have custom springs designed and built that allows you ro have un limited travel adjustmeant but not risk reliabitly probleims?

  16. #16
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    the spring has to be stretched. if you look at the picture i posted you'll see that there is a small area, three coils, of the spring that is 'bunched up'. what you need to do is take an acetaline torch or similar torch and heat it up alot. then just take a screw driver or something and spread em apart. its kind of a timely/invovled process but it works. this needs to be done to allow the little plastic threaded thing to wind further through the coil.

    in theory you could create a spring that would let you easily go from whatever the max on the fork is(cant get any longer then that) to zero, with whatever stiffness or reliabitlty risk. it would be very difficult because you'd need to attach it to the top cap which the spring is kinda scrunched around. if you look at the picture, again yo ucan kinda see this.

    hope taht answers your questions man. lemme know if you got anymore

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