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Rear Suspension Question

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First, I'm by no means a suspension expert and this is in fact the first time I've tried to tune my suspension myself.  Working on a new-to-me 06 200XC with about 100 hours on it...

 

I've watched several how-to videos of getting the static sag set by adjusting the preload on the shock as well as followed the manual step-by-step.  I've adjusted the ring so that I have 35mm of static sag.  My question is the manual states that there should be about 0.2 inches for a "standard preload", however to get my shock's static sag set to 35 I've really had to crank it way down.  I have about 1-1/2 inches to the TOP of the ring which, to me (the non expert), seems like a lot.  Could there be something else going on with the shock that would cause me to have to make such a large adjustment on preload just for the static sag?  There's not apparent oil leaking or anything that would visually appear to be wrong with the shock.  Also, I did not reset the rebound or compression back to factory recommended settings before working on the sag.  It doesn't seem like they'd be related but there's a strong chance I'm completely wrong about that!

 

I haven't made the last measurement yet to determine my riding sag but I'm 99% sure I'm going to have to move up to the heavier spring.  I weigh about 170 + gear so I'm almost positive a new springs are in order, front and back.

 

I'm not a beginner rider but I'm also not a pro, don't race, and don't plan to, so sinking a ton of money in to the suspension is not something I plan to do.  I merely am trying to get the factory recommended setup for ME on this bike.  Any advice on getting a basic setup on my ride would be very much appreciated!

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I believe that .2" standard preload on the spring is actual preload on the spring, meaning, from the point at which screwing the nut down contacts the spring and then screwing it down another .2" from there to get standard/minimum preload.

The 35mm static is how much the bike sags under it own weight only. You measure that by making sure the rear suspension is completely extended, like when the bike is on a stand, then measure from the rear axle up to a reference point on the fender. Then take the bike off the stand, hold the bike upright and let the suspension sag under the bikes own weight. Take the measurement again from the same two points. It should be around 35mm less. "Thats your static sag" .

With the nuts cranked down on the spring like you're talking, the bike probably doesn't sag at all under its own weight, zero static sag.

Once you have the nuts adjusted to give 35mm static as described, sit on the bike, feet on the pegs, hold yourself upright by holding onto a wall or something and have someone take the measurement again for you at the same to reference points. The difference between suspension fully extended to you sitting on the bike is your race/total sag. I don't know what the recommended figure is for a 200 but I'm guessing its around 100mm.

You adjust the preload nuts to try to get as close as you can to both the static and total sag figures. When your spring is not the right rate for your weight, you compromise with your sags. Like with you being 170lbs, the spring may be too light for you, so to keep the rear from bottoming on you, being too plush, you may have to preload the shock more, making your static less than 35mm..

When a spring is too light, you can preload for the total amount of sag you want or for static sag, one or the other. As I said, its a compromise, get them as close as you can and ride it til you can afford to spring it for your weight.

Edited by Trailryder42

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Maybe I didn't explain this well enough. I started with about 47mm of static sag and I got that by the exact method you described...measured on the stand, took it off compressed the shock once and then measured again under its own weight just like the manual says to. I then adjusted the ring down until the difference in the 2 measurements were 35mm. The suspension certainly has the correct amount of sag however I really had to crank it down to get it "properly" adjusted. So does that mean anything is wrong with the shock? Since I had to make a big adjustment just to get to the right static sag?

Thanks for your detailed response!

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You have 1.5 inches to the top of the ring, which I assume you mean the top jam nut, "from where"? You gave one point of reference for your measurement, the top of "the ring" , whats the other point of measurement?

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That's a very good point, I should have also explained that better.

 

Here's where I've adjusted it to.

 

20140526_200413.jpg

 

And me trying to hold a tape while also taking a picture....

 

20140526_200509.jpg

 

My 1-1/2" (+/-) measurement is from the top thread to the top of the jam nut as pictured.

 

My first time trying to post pictures so hopefully this works.

 

Thanks again for your help, I really do appreciate it!

Edited by wesc

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I see different colored threads about 1/4" above the lock ring. Is that where it was when you had 47mm static sag?

Is that what you're calling really having to "crank it down"?

You're right, not having backed off the comp or rebound has nothing to do with setting sag. If the shock action is controlled and doesn't act like a pogo, there's most likely nothing wrong with it.

For an '06, Its possible the spring has been swapped by a PO at some point, maybe even the wrong spring. But I don't think that 1.5" is anything to worry about. Its pretty similar to every other shock I've ever dealt with.

Is there a number stamped/printed on the spring that we can look up and verify what spring it is?

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Yes and what I should have said was that, to me, the total preload both before and after my adjustment is cranked down. I believe I turned the lock ring 4 full turns to adjust the 12mm out of it.

The spring is a 72-250 which according to the manual is the stock spring. Like I said, fairly certain I'm going to have to respring but before I do that I wanted to make sure this large preload isn't an issue.

I'm still going to do the final measurement for the racing sag but I believe it's going to tell me to bump up the spring.

Thoughts?

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these bikes like more sag, 120-135 for race sag, 35 for static. Your idea of if something is wrong may be bad lower bushing for the shock to swingarm or no gas in the shock. The minimum shock ring preload is 2mm not inches. For your weight you will need heavier springs both ends. The above described way to measure race sag is not fully explained. If you are a sit down rider then do as above, if you are a standup rider then measure while standing on the pegs. Measure the fork sag by putting a zip tie on top of the chrome tube and sit on bike, it should sag about 1/3 of travel.  

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Yes and what I should have said was that, to me, the total preload both before and after my adjustment is cranked down. I believe I turned the lock ring 4 full turns to adjust the 12mm out of it.

The spring is a 72-250 which according to the manual is the stock spring. Like I said, fairly certain I'm going to have to respring but before I do that I wanted to make sure this large preload isn't an issue.

I'm still going to do the final measurement for the racing sag but I believe it's going to tell me to bump up the spring.

Thoughts?

I agree, new springs of the proper rate for your weight would be the ticket, but no worries about the amount of turns it took to preload it another 12mm. It won't take that much with a stiffer spring.

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Thanks again for the help.

One last question, any recommendations on where to buy the front and rear springs?

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