950 SE rear shock.

Discussion in 'Dakar champion (950/990)' started by Pitster, Aug 17, 2016.

  1. alongat

    alongat Fesh Fesh

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    I need to dig up the details. I’ll post here later
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  2. Misery Goat

    Misery Goat Positating the negative Super Moderator

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    Does anyone know if this is a short reservoir? It has five rings and I think that means it is but I'm not certain.

    [​IMG]
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  3. Chalk

    Chalk Been here awhile

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    It’s the short one
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  4. alongat

    alongat Fesh Fesh

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    +1 it’s the correct one
  5. Misery Goat

    Misery Goat Positating the negative Super Moderator

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    Thanks, I'm going to check it out.
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  6. Misery Goat

    Misery Goat Positating the negative Super Moderator

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    Ok, I've re-read the thread and I think I've confused myself on the springs.

    My SE has stock 59 fork springs (running Safari tank), OEM shock and spring 140-215. I'm 5'10" 77KG without gear. I always ride with tools and roadside kits, and camping gear for longer trips.

    The only time my SE has felt right offroad is when it's fully loaded. I can ride much faster/more aggressive in this set up:

    [​IMG]

    When the bike is not loaded it's almost unbearable offroad, the rear bounces and doesn't maintain contact when I'm riding aggressive.

    I don't want to change the height of the SE if I can help it. I think that translates to a 130-265 Spring and thinner internal spacer? Does that sound right? Apologies for being thick.
  7. alongat

    alongat Fesh Fesh

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    Yes - the 130 is the lightest WP spring I’m aware of and sounds right for your weight. The only thing is that it will raise your seat height by about 10mm...but unless you crank the preload up, I suspect the height will be fine once you’re sitting on it.
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  8. skuikka

    skuikka Been here awhile

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    Ask someone who has a lathe to make you a 7,5mm spacer and use a 130-255 spring if you are worried about the height. This will give you stock height. I've had this setup for a couple of months now. Like it alot.
    I'm tall but I enjoy playing in Hard Enduro tracks so I want to get my foot down for kicking rocks and things. Raced one GNCC a couple of weeks ago, worked like a charm on faster stuff too.
    That is if a 130-255 spring exists. Alon?
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  9. alongat

    alongat Fesh Fesh

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    I’ve had zero luck finding a 130/255...agree that the internal shim (spacer) can be easily built up or remade to a thicker spec to limit the shock extension if required.

    The other way round this is to make a 245mm travel Adv shock which needs:
    1- one Adv shock with the short reservoir
    2- an Adv 130/140/150 x 225mm spring
    3- use the 10mm thick internal spacer instead of the thinnest one mentioned in this thread
    4- reuse the 25mm thick external spacer that the Adv standard shock comes with and add 9mm-10mm of additional spacer on it (very easy to find or have made)

    This is what I had made for @MultiDoc for his SE as he’s not particularly tall or heavy. His seat height ended up about 4-5mm below the stock height. The result is the same 9mm preload as with the long version. That still gives you nearly 16mm more of preload available to you to add via the preload adjuster.
  10. charlie264

    charlie264 Long timer

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    Misery, the longer the spring the more the intial give. Someone correct me, the 140Nm equates to 14kg/mm travel resistance.
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  11. Misery Goat

    Misery Goat Positating the negative Super Moderator

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    Thanks, I don't think 10mm will make much difference. I want to make sure I'm not lowering the bike and screwing up the geometry. I get confused pretty easy with suspension adjustments. I have a 32" inseam and like the height of the SE, I don't paddle or put my feet down much when I'm offroad.

    Ok, so going this route I could use the spring that comes with the 990 shock. Won't the 150 be a bit much for my weight and lesser weight of the SE? It'd be nice if I could use that spring. So I need a thicker spacer for a shorter spring. This seems counterintuitive to me.

    Thanks for the replies, I'd like to get this sorted, I've sort of fallen out of love with riding the SE since my trip as I don't have all this gear on the bike when I'm riding and it gets unpredictable at speed.
  12. alongat

    alongat Fesh Fesh

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    Yes - the 150 rate spring will be too stiff for SE+your weight. Either way, the 130 rate is the way to go.
  13. alongat

    alongat Fesh Fesh

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    Think about what’s going on:
    1- you have an internal spacer that limits how much the piston rod will extend out of the body of the shock. When this internal spacer is thick, the rod protrudes less and limits overall shock length which contributes to height and travel
    2- the external spacer is what Ktm stacked on top of the 225mm length spring to achieve the inherent preload they wanted when factoring the overall length / travel

    So for number 1, a thinner spacer allows more of the rod to protrude and when combined with the 255/265mm length springs, you achieve both the inherent preload (in this case, 9mm or so) plus the overall shock length / seat height / travel you want. If you use a thicker internal spacer, the overall length will be shorter because the rod won’t protrude out as much PLUS you’ll increase the inherent preload on the longer springs.


    Does that make sense?

    Also, don’t worry too much about your seat height going up 10mm. When you sit on the bike, your weight will push the bike down (rider sag) more with a 130 rate spring than it will with a 150 rate spring (you’ll have more sag; the difference between the bike’s height under its own weight vs the bike’s height with the rider on it as well) and you’ll end up where you want to be whilst riding.

    There is a general magic formula to follow when calculating desired rider sag and I’ll bet at your weight, you’re not even close which means the current spring’s rate is too high for you. I have the opposite issue with weighing about 26kg more than you :)
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  14. alongat

    alongat Fesh Fesh

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    And lastly, you will now have an easy preload adjustment on the Adv shock to increase preload when travelling with luggage or any damsels in distress you find trailside...more weight? Just crank up the preload up to an additional 16mm I think.
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  15. Misery Goat

    Misery Goat Positating the negative Super Moderator

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    Yup, that makes sense. It sounds like I should try the 130/265 spring with a thicker spacer and see how that goes.
  16. alongat

    alongat Fesh Fesh

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    What do you mean thicker spacer? The internal one? If you’re planning to use a 265mm spring then you need to use the thin internal shim (spacer) otherwise there will be too much preload on the spring.
  17. Misery Goat

    Misery Goat Positating the negative Super Moderator

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    Damn, I conflated my thoughts.

    Option 1 - 130/265 - thinner internal spacer and no external spacer
    Option 2 - 130/225 - thicker internal spacer and external spacer

    Is this correct?

    How thick is the OEM internal spacer that comes with the 990 shock?

    Edit - I need to look at this image anydavenow posted to keep things straight.

    [​IMG]
  18. Misery Goat

    Misery Goat Positating the negative Super Moderator

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    Ok, so I'm not certain about my previous post.

    I had my OEM SE shock made into a PDS, pin, valves, etc, a few years ago but the OEM spring has prevented me from appreciating it I think. So, in the mean time I've installed a 130/215 spring to see if that helps soften up the low speed handling. I'm at around 5mm of preload and I ran the bike on asphalt and it's noticeable softer. It's a little twitchy at >80mph but it doesn't go into the death wobble so I'm close I think. I wonder if this spring will be enough for camping gear though. I'm going to try to get out this weekend and test it if I can keep from melting. :D
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  19. Bonnie & Clyde

    Bonnie & Clyde Wishing I was riding RTW

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    I like my TT tractive Shock loaded or unloaded. Very adjustable and plush
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  20. charlie264

    charlie264 Long timer

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    Off topic. My £30 quid shock, need a lot of TLC...to the point of binning it. The high speed rebound was sized solid....and I broke the adjuster. Anyhows its now completely stripped and I'm assuming the needle valve should move in the bottom bush? Its been soaking in WD for over 24 hours and still wont budge. Its quite delicate so I don't want to damage it.....Anyone enlighten me please?

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