How to service (some) LC4 forks

Discussion in 'Thumpers' started by meat popsicle, May 7, 2008.

  1. Dolly Sod

    Dolly Sod I want to do right, but not right now

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    I would just disassemble and compare. It's not that difficult to get down to the point where you can see if a swap is possible.

    Also if you're just trying to reduce the travel of the SE forks, I believe that can be done just by adding some spacers internally. No need for a swap.
  2. mousitsas

    mousitsas Long timer

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    You are right on both counts.
    In the case of the spacer I would need shorter springs, a cost I would like to avoid if possible. How bad an idea is to cut the existing ones? What puzzles me a bit in this case is that if I cut them shorter, I will not have the nice flat top of the oem. How important is that?
  3. Dolly Sod

    Dolly Sod I want to do right, but not right now

    Joined:
    Aug 18, 2003
    Oddometer:
    18,873
    Location:
    Richmond, Va

    I know many people cut down fork springs. I know the flat spot is important because as your springs compress they twist. If you have a rough end on the spring it is going to dig in to whatever it is pressing against.

    At a minimum you'd need to grind the end flat, and I suspect you'd be best off heating the end and bending it flat to mimc the original. I've never cut a fork spring before. So I'd get a second opinion on this.
    mousitsas likes this.
  4. meat popsicle

    meat popsicle Ignostic

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    hey mousitas,

    I can't say if swapping internals might work or is a good idea. I do recall there was some chatter about cutting for springs... I'll have to look if it was a good idea or bad one. I do recall shortening the travel of a rear shock with dog bones is a bad idea, probably because it would put lots of preload on the spring, but again this is from memory. OK, here's one:

    http://advrider.com/index.php?threa...orks-have-i-just-bought.933312/#post-22743156
    http://advrider.com/index.php?threa...s-sign-in-please.35110/page-524#post-30731088
    http://advrider.com/index.php?threa...s-sign-in-please.35110/page-525#post-30740182

    Gunnerbuck is a good inmate - I trust him. Says that shortening the spring will increase the spring rate - that may or may not bother you, but its good to know before you bother.

    If you want to talk to some pros here's the best in my area: https://superplushsuspension.com/adventure-raising-or-lowering/ They do answer email and their phone; probably give you some advice.

    Quick search for ya:
    http://advrider.com/index.php?threads/the-ktm-690-enduro-thread.1048049/page-313#post-34354010
    http://advrider.com/index.php?threa...spension-related.422445/page-36#post-28444841
    http://advrider.com/index.php?threads/ktm-690-adventure-re-build.1016239/page-2#post-26259860