SE 950 rear springs/race sag info

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by Navin, Feb 5, 2012.

  1. Navin

    Navin Long timer

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    Got the old gals legs rehabbed, two stage valving up front replaced the goofy "what were they thinking" valving. Rear shock got some tweaks too and now I'm focusing on my race sag.

    My uses are all off road and mostly sandy at race speeds. With the stock spring I'm able to dial it back to one turn of the preload ring to achieve 2-7/8" of sag. I'm thinking I want at least 3.35", maybe even closer to 4". Stock truck spring has to go. Anyone else at around 200 lbs have experience as to what spring will give what sag #s?

    If anyone has a weight/sag/spring just add it here please. Hopefully this can help everyone dial them in with less guessing.

    Anyone running progressive spring too? Love them on my smaller PDS race bikes.

    Thanks!
    #1
  2. mousitsas

    mousitsas Long timer

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    You can calculate the spring you need.
    What matters for you is the difference between the bike sag and the bike+rider sag. This difference depends exclusively on your weight and the spring stiffness.
    If the current difference is Dstock and you want to achieve a difference of Dnew then you simply evaluate your new spring by the formula 140*Dnew/Dstock where 140 is the stock SE spring stiffness. Of course that's what theory says, because springs are never absolutely linear, and there is also a built-in 'progressive-ness' due to the geometry of suspension but it might be a good starting point.

    However, bare in mind that fitting a new spring may require new valving.
    #2
  3. trailtrick

    trailtrick goat trail rider

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    I run a 11 and 12 on mine before i swap to progressive 12.5- 15 .
    sag around 3"
    #3
  4. Navin

    Navin Long timer

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    Javier, what is your rider weight? Were you bottoming the 11 or 12 alot? Riding loaded up or 2 up? I ride solo 99%. You think 3" is enough sag?
    #4
  5. trailtrick

    trailtrick goat trail rider

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    ready the ride 220 lbs,iever bottoming the 12,i like the progressive better because o the feeling in outs and big drops in the desert,
    3 inchs was were i nlike it most , more sag and the front end din't stick like i like it,less than 3 inchs and the front end gets to twichy.
    #5
  6. Navin

    Navin Long timer

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    Was that you never bottomed the 12 or you were ever bottoming, like forever bottoming? Sorry buddy, hard to read that one! :ear

    It is hard to believe this pig can feel twitchy! :rofl3" sag it is I guess.
    #6
  7. crankshaft

    crankshaft Guns are for pussies

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    Looking forward to seeing how you make out, I was pondering my suspension this weekend. I did a stage rally in the sand and the big girl was was whipping the h-bars all over the place at 100MPH in the sand ruts. I think I was riding a bit high in the back and had to much steering. I pulled some compression out of the rear and slowed the rebound a bit on a service break and it got much better.

    I've got the SP suspension currently and I haven't really adjusted anything other than the rear shock and adding a few clicks of compression to the front.
    #7
  8. trailtrick

    trailtrick goat trail rider

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    the bike bottoms only in big g outs o square ruts were i was coming short .
    #8
  9. Navin

    Navin Long timer

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    Thank you TT! I'm hitting these numbers with the stock spring at my 200lbs

    One turn of preload on the spring
    35mm bike sag
    73mm race sag

    I'm looking at the typical recommendations that say to shoot for 1/3 travel, or around 85mm race sag, up to 1/10th or 25mm max bike sag and no more than 8mm of preload on the spring. I'm not going to get these numbers, or even close, with the stock 14 spring as it is zero preload now. How much softer should I be going to get in the ballpark or are these numbers useless on the SE?
    #9
  10. mousitsas

    mousitsas Long timer

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    I think in the SE is more important to set ride height correctly, rather than try to apply the general rules of off-road suspension setting. These ballpark recipes are made to work on lighter bikes with half the power.
    #10
  11. Navin

    Navin Long timer

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    I'd like to at least have the rear suspension go thru the stroke though. Right now I can barely move it. 73mm of race sag and if I bounce on it I doubt it moves beyond 74mm, it's like sitting on a barstool! :lol3

    I'd rather be bottoming it a few times a day than having it pound the front forks. I have no doubt the rear made the front feel worse than it really was before. TT has a few lbs on me, and I'm running a 2-1 FMF out back, no weight added out back ever. I guess somewhere sub 12kg is where I'm headed.

    Mousitas, what spring and sag numbers/weight are you getting?
    #11
  12. mousitsas

    mousitsas Long timer

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    About 3cm static and another 3cm when I climb (pun intended) on the bike. I weigh about 95-100kgs with gear.
    I couldn't take more accurate measurements as I was by myself, but will pm you them when I find a victim with the gift of common sense. Standard spring, twin akras and shock on sports settings. Up front -4 turns preload with stock springs and the adv-r valving.

    Works fine for me but I ride exclusively on asphalt and rocky terrain when off-road. Tried also a 130 spring, but I found it soft for my liking.
    #12
  13. Black Hills

    Black Hills Long timer

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    standard sag is around 5-10% of total travel for static sag and 25-30% for rider sag. I use these numbers on about everything and they seem to work very well.
    #13
  14. kanur

    kanur cu new er

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    Forgive my suspension noobness but where are you measuring the 3.35". I might get to 200# with gear on and like you said it is like sitting on a bar stool.
    #14
  15. Navin

    Navin Long timer

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    Measure race sag by getting the bike off its wheels, measure a fixed repeatable point from the swingarm to the fender for example. Now put the bike on the ground, sit in a neutral position and balance on tip toes or have a 3rd person balance the bike by the bar end, repeat measurment. Subtract that from first measurment and you have race sag. Measure again on ground, no rider, subtract that from first original measurment and you have bike sag. I bounce the bike between each step after I sit on it or exit.

    Conventianal wisdom dictates a rough starting point of 1/3 of total travel in the rear as a base race sag setting. We have 10".
    #15
  16. kanur

    kanur cu new er

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    Thanks Navin,

    My race sag is around 3 7/8" and bike sag is 2 3/4". These are rough measurements as I was by myself, I'll get the misses to help me get better ones.

    I have all the clickers set to the comfort settings plus a couple clicks and the forks are pulled up 3/4" in the trees. I have the spring preload backed off a lot but have not backed it off till loose, I need to do that and see where I have it.

    Again thanks for starting this topic, I'm finding it most useful.
    #16
  17. Navin

    Navin Long timer

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    You must be a big dude! I think getting a good measure by yourself is near impossible but if you pulled it off great!

    Stock spring (?) and your weight Kanur?

    I've got a 12kg on the way from TrailTrick. I'll post up my numbers when it gets here.
    #17
  18. kanur

    kanur cu new er

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    Not big at all, 180# in street closes. I'm pretty sure the spring is stock as I bought the bike from the first owner with 2000 miles on it and everything else was stone stock and he was a big guy.

    I'll have to check again when I have help. I'm lucky I didn't fall over while trying to sit on the bike backwards and measure it :huh:eek1:rofl:rofl
    #18
  19. Navin

    Navin Long timer

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    I think you may be off in your measurments then as I'm 20lbs heavier and can't get 3" of race sag with zero preload on the spring.

    2.78" of race sag
    1.37" of bike sag

    Even if you have stock rear dual cans compared to my 2-1 FMF we should be close in these specs. If not, you have a different spring or more gravity where you live! :lol3
    #19
  20. Black Hills

    Black Hills Long timer

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    rider hieght and where they position themself on the bike makes a big difference in setup. that is why you should take measurments in your normal riding position.
    #20