640 Adv suspension settings

Discussion in 'Thumpers' started by Buckster, Aug 6, 2004.

  1. Buckster

    Buckster Banned

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    I am about to start playing with the suspension and was wondering what other folk had set theirs up to, I weigh about 200lbs, I think I need to up the front pre-load and the rear pre-load and maybe rear re-bound.
    #1
  2. Velocibiker

    Velocibiker Adventure Antagonist

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    IMHO - Suspension, like oil and helmets has too many opinions. I recommend you start with the factory settings from your OM and go from there.

    There's no way to attach documents to posts or I'd give you a couple documents I've aquired over the years that I've found beneficial. There are plenty of sites devoted to suspension set-up as well.

    Not much help I'm afraid....
    #2
  3. creeper

    creeper Still alive...

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    Adventures are under sprung for a 200 pounder. (Hell, they are under sprung for a 180 pounder) Without changing springs... you will need to up the compression a bit and back off on the rebound.
    Why? As I said, the springs are a bit too soft a specification; you'll need to up the compression damping to compensate. As to the rebound... you need to reduce damping... to compensate.
    The rear especially, will "pack up" over stutter bumps and ridges if you don't back off rebound.

    Try it... what do you have to lose?

    If your riding in anything other than sand, slide the forks up in the trees about 10-15mm, bike will steer better.

    Creeper
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  4. Buckster

    Buckster Banned

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    Don't know if the '04 or European model is different but the bike is not undersprung at the front at least, possibly the rear but even then unlikely, I find the steering fine and do not want to alter the rake.
    #4
  5. Rad

    Rad Done riding

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    I'm not a good suspension person and the 640 Adventure has far more adjustments that I've had on a bike before.

    It took me way to long to figure out the combo of more compression and less rebound :nod
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  6. paulsax

    paulsax Paul

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    This website might help a little.

    http://www.4strokes.com/tech/racesag.asp

    In a nutshell set your sag up for you and your gear sitting on the bike.
    Get a buddy to measure. THen set up you compression and rebound to your
    feel. THe results you get for the sag measurements will let
    you know if you need new springs. Once you know that and have
    your sag setting you
    can tweak sag if you want for occasional loads or fine tune
    your handling. On the compression and rebound clickers
    remember to never crank them tight (turn gently) and always
    count from full in. So a setting might be "4 clicks out" which is
    to say 4 clicks out from all the way in. In is usually clockwise
    by the way. SOme bikes are different like the PDS KTM rears
    but I don't think the 640 is PDS. FOr setting compression and
    rebound start with a reasonable setup like the factory recommended
    or maybe 1/2 way out on compression and 1/3 of the way out in rebound. Then go to a short section of trail or whatever that is like what you want
    to tune (optimize for). Ride over the section and try to notice
    what you are feeling. Make an adjustment and ride the section again
    and see what happens. If the section is short it's easy to compare settings.
    Too long and you forget what the last setting felt like. If you get your
    setting where you like them and sag is correct you can tweak your handling
    by small rear sag (couple mm) changes and or small changes in the fork tube height. Raising the forks 5mm in the clamps up front makes a big change in how things turn. Remember to torque the clamps correctly and if you
    want more that 7-10 mm correction up front look around because its getting a bit much. I move mine usually no more than 5mm. Tons of other info on the web as well.

    good luck

    paul
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  7. Velocibiker

    Velocibiker Adventure Antagonist

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    Nice, excellent advice. I'm glad you were willing to pound the keyboard :D

    I agree 100%. :thumb

    One other thing to consider if you plan on hanging bags for extended pavement rides and then drop the bags while riding in the dirt;

    I measured my sag both ways. Split the difference and that's where it stays. Now I just have to make adjustments to rebound & damping depending on if I'm running pavement twisties or desert trails. Overall I've found the WP suspension just fine for all my riding. Not undersprung at all...

    YMMV. Set it right the first time and tweak it from there. Then ride the snot out of it!!!
    #7
  8. ktmnate

    ktmnate Long timer

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    Yea, what he said. I found for the street the stock was OK. However for the dirt, when the compression was dialed up, was not fun. In the dirt the front would get choppy and start bouncing around turns. I didn't like that and ended up getting the suspension re-sprung and re-valved. What a diffeence. It's like riding a lincoln town car, only better.

    ps -I weigh 210# and need good suspension of offset my crapy riding.
    #8
  9. creeper

    creeper Still alive...

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    Or a nice suede seat... maybe? :lol3
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