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why is my static sag out?

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hey guys, after ringing many companys, bike tuning shops and suspension specialists i was told by countless to buy and install a 4.8kg/mm rear shock spring..

just finished installing it, and my static sag is at 48mm

unloaded on stand - 620mm

Loaded with all gear - 520mm

Unloaded OFF stand - 572mm

so i set my Race sag spot on 100mm

but my static is still out? and i had 7 companys (including racetech) tell me to get a 4.8kg/mm..

so whats the go? am i missing something?

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How much do You weight driving gear on?

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way too stiff you need 0.41 and 4.5

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Yeah but I'm mainly doing motocross so that's why alot told me 4.8... I'm guessing

How do I get it closer to 30 - 40mm Static? Adjust preload? Run 110mm?

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The static sag is not as important as rider sag, unless of course your bike rides around a lot without you on it. Rider sag sets the rear suspension in the right position within the travel arc so that it can maintain good tire contact. The comparison of static sag to rider sag is only a gauge of how correct the spring rate is.

That being the case, the only right way to correct the static sag is by changing the spring rate. However, the 100/25 rider/static "rule" is really just a guideline, and some will run a spring either lighter or stiffer than the one called for by the rule. In your case, you'd need to reduce the spring rate to get a lower static sag number. And frankly, 4.8 does seem a bit much for someone weighing 138 pounds in his riding gear. (What did these people say about your fork springs??)

Also, I've seen a number of posts here regarding Honda CRF250's (either model) that have noted rider static sags in the 30-40 range, so the linkage ratios and such can enter into the situation, too. Either try multiple rates, or take a recommendation you trust and go with it. But set the rider sag based on what makes the bike handle best, and don't worry too much about the static.

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I have .42 for the front..

And they bike wasn't bad before at 5.2 I got used to it. So it'll be better now I guess anyway

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Both sags are important. But if you must fudge till you get correct spring get rider sag correct. But you don't have right sring till both static and rider sags work out.

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How much pre load is on the spring ?

With him having 100mm race and 48mm free/static, I'm thinking, very little preload currently.

90-105mm is usually the recommended "range" of race sag, so put some more preload on it, bring the race sag down to 95mm and see how much closer that gets you to the free/static you're thinking it should be.

Readjust compression and rebound clickers if you need to.

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With him having 100mm race and 48mm free/static, I'm thinking, very little preload currently.

... bring the race sag down to 95mm and see how much closer that gets you to the free/static you're thinking it should be.

44mm would be my guess.

It occurs to me that with such a light spring and low level of preload, static friction ("stiction") may be causing a problem with the readings you're getting. When you measure static sag, compress the shock a bit and let it up very slowly, then measure. Then lift the weight off the rear and release it slowly, and take another measurement. In an ideal world, there would be no difference, but 5-10mm isn't unusual. Yours could be even higher.

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How does the bike feel with the new spring on it? I promise you know one will know your static sag is off when your ripping around the track. Try it.

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How does the bike feel with the new spring on it? I promise you know one will know your static sag is off when your ripping around the track. Try it.

Very true.. But I was just going by what I was told. I'll give it a few hours and some testing and adjusting and see how we go. Thanks very much guys.

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