DR650 Shock Rebuild

Discussion in 'Thumpers' started by P-nut, Jan 14, 2008.

  1. P-nut

    P-nut Adventurer

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    For those of you that are interested a friend has been developing a shock for the DR650. He is using the body and the spring of the stock shock. Everything else is new. It has compression, rebound, and ride height adjustments. I rode his bike last week and it was a huge improvement. I saw the biggest difference on washboards on gravel roads. I just removed my shock and we are going to rebuild it tomorrow night. He already has a completely new shock for the KLR and some Ducatis. We are going to take pictures of the whole thing. I may need some help posting them.
    #1
  2. neepuk

    neepuk Such a drag...

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    Sounds cool. How much do you weigh? How are you using the stock spring with any success? Just seem to me that once a soft spring, always a soft spring... Try your new shock with a new spring too, unless you're very light:evil.

    Love to see those pix when you take them. :ear
    #2
  3. Rusty Rocket

    Rusty Rocket Life behind "Bars"

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    I'm staying tuned to this one.
    #3
  4. P-nut

    P-nut Adventurer

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    I weigh 175 lbs and the stock spring rate ( .470 kg/mm) is a little more than what is recommended (0.455 kg/mm)for my weight. I got these numbers from Race Tech's website. Keep in mind, I have already ridden a DR with this shock (using the stock spring). He was previously using the gold valve kit from Race Tech.
    #4
  5. BurnieM

    BurnieM Nipple boy

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    Are you sure that is right ?

    They sound like the fork spring rates
    .
    #5
  6. NordieBoy

    NordieBoy Armature speller

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    The stock spring rate is 6.5kg/mm for the rear shock.
    Most of us in the 180lb range are using 7.6kg/mm rear.
    0.47kg/mm is the recommended front spring rate for 180 odd lbs.
    #6
  7. P-nut

    P-nut Adventurer

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    Your absolutely right. I checked again. 5.4 kg/mm is the measured stock and 5.32 kg/mm is the recommended spring.
    #7
  8. P-nut

    P-nut Adventurer

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    #8
  9. NordieBoy

    NordieBoy Armature speller

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    This was my e-mail from Jesse and when I went to the RaceTech site it came up with the same numbers.
    I also wanted to see what weight you had to be to have them recommend the stock spring weight and it came out at 45kg :D

    They must have changed the site as it now it comes up with your numbers above - Weird...

    :EDIT: If you enter a 2001 bike it says it can't do shock springs and if you enter a 2000 year it comes up with my numbers.
    Looks like they have different numbers in their database for different years but the actual springs on the bikes didn't change - Weirder and weirder.

    Both Jesse Kientz and Norm Kouba recommended the same .47 fork and 7.6 shock springs to me.
    #9
  10. neepuk

    neepuk Such a drag...

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    I'm not trying to rain on your parade in any way. I'm excited to see how this whole thing turns out and I support your idea fully. That said..... You NEED to change the spring. You're gonna valve this thing soooo stiff trying to compensate for lack of spring, then when you get the right spring you'll be starting all over again.....

    Hell, I may not know what I'm talking about but I just don't see it working very well with the stocker.
    #10
  11. P-nut

    P-nut Adventurer

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    This is by no means my idea, I'm just the guinea pig lucky enough to try it out. I'll take the spring into consideration. The shock will be in and out of the bike a few more times in the next couple of weeks. We finished assembling the shock tonight. I took alot of pictures and I will try and post them as soon as possible. The plan is to ride it this weekend, then remove it again and get the body hard anodized. While it's out we will make anymore changes or adjustments if needed.
    #11
  12. radguzzi

    radguzzi The Journey is the Reward

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    Ditto... :lurk
    #12
  13. DRinda505

    DRinda505 I'm right behind you.

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    :lurk
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  14. NC Rick

    NC Rick Cogent Dynamics Inc

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    It's less $$ than a poor condition Trail 90:D

    I want one of those too1
    #14
  15. eakins

    eakins Butler Maps

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    i'm interested but also thing your spring rate is wrong.
    #15
  16. P-nut

    P-nut Adventurer

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    [​IMG]

    The stock shock.
    #16
  17. P-nut

    P-nut Adventurer

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    [​IMG]

    The spring removal.
    #17
  18. P-nut

    P-nut Adventurer

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    [​IMG]

    The stock piston and shaft.
    #18
  19. P-nut

    P-nut Adventurer

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    [​IMG]

    The salvaged body. This was in surprisingly good condition considering it has 20,000 miles on it. The body will be hard anodized next.
    #19
  20. P-nut

    P-nut Adventurer

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    [​IMG]

    The new head seal. The one shown is threaded. The one used in the DR is not. Other than the threads they are the same. We already assembled the one going into the shock so we used this one to demostrate.
    #20