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Confused on static sag

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I have the 2010 yz450 and they say on these late model bikes that a sag of 98mm to 102 is reasonable and to have no more than 25mm or less of static.

Like the bike is (stock) I used my sag scale and marked a place on the number plate and set the scale at Zero. When I sat on the bike and had my friend to see where it went to it was 102mm and then we measured the static and it was 38mm.

I thought the shock felt stiff to me this past sunday at the track. It felt like it didnt want to squat any and it just wanted to stand up around turns and not soak up in the turn. Also when jumping this triple jump, when I landed it felt kinda hard.

The forks were stiff also and made my wrists hurt when landing off of big jumps. I could feel the ground through the grips.

Do I need to turn my shock counterclockwise (lengthing the spring) to make it a little softer in the rear? (but that would give me a smaller sag reading wouldnt it?)

Or do I need to turn the shock clockwise(shorting the spring)(more tension)

and make my static sag more toward the 25mm range?

I guess what I'm asking is ........ How do I get around 25mm static sag and have a race sag of 98mm-100mm

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Those numbers are saying you need a softer spring. The spring is stiff enough to hold you up with very little preload, which is why the static sag is so large. Sounds like new springs front and rear. Most of the suspension companies have online spring calculators.:thumbsup:

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This is for a 2004 YZ450 (below just as a example) , but the point being that there is a minimum and maximum on how much you can tighten or loosen the spring , if you go beyond those settings then you are compromizing the ability of the suspension to work properly , so you need to look at the manual(you do have a manual dont you??) and go by the settings it shows , if you weigh more or less than what the manual says, you will most likely have to re-spring the bike , if you follow the guidelines in the manual and check your sag and it does NOT fall in the guidelines when adjusting to either limit then you will have to re-spring for your weight , no other choice !

Stiffer → Increase the spring preload.

(Turn the adjuster 2 in.)

Softer → Decrease the spring preload.

(Turn the adjuster 2 out.)

Spring length (installed) a:

Standard length Extent of adjustment

249 mm (9.80 in)

*264 mm (10.39 in)

240.5 ~ 258.5 mm

(9.47 ~ 10.18 in)

*255.5 ~ 273.5 mm

(10.06 ~ 10.77 in)

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yes you need a softer spring, but only IMO one step down, and then i think you may still need a softer valving setup, how many hours you put on it?

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Those numbers are saying you need a softer spring. The spring is stiff enough to hold you up with very little preload, which is why the static sag is so large. Sounds like new springs front and rear. Most of the suspension companies have online spring calculators.:thumbsup:

I believe I should be able to adjust the race sag a little to come fairly close to the static sag couldnt I? Cause I was thinking that this 2010 yz450 was sprung for riders in the 175lb-200lb catagory.

Thats why I ask if I can fine tune my race sag to get a closer static sag? If so would I take the rear spring up the shock body to lower the static sag?

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yes you need a softer spring, but only IMO one step down, and then i think you may still need a softer valving setup, how many hours you put on it?

Just about an hour and a half.

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i would leave it at 102, you could goto 100 i guess to get better steering, and that would give you maybe 36mm static, which is closer, have you tried winding out the compression high and low speed?

it will not feel as plush as it can till about 10 hours riding.

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i would leave it at 102, you could goto 100 i guess to get better steering, and that would give you maybe 36mm static, which is closer, have you tried winding out the compression high and low speed?

it will not feel as plush as it can till about 10 hours riding.

Thats what I was thinking,but wasnt sure. I will try it at 100mm for the next ten hours and see how it does and soften up with the clickers some.

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I believe I should be able to adjust the race sag a little to come fairly close to the static sag couldnt I? Cause I was thinking that this 2010 yz450 was sprung for riders in the 175lb-200lb catagory.

Thats why I ask if I can fine tune my race sag to get a closer static sag? If so would I take the rear spring up the shock body to lower the static sag?

What is your static sag when race sag is 100mm? (Straight line from center of the axel to the rear fender). When you are measuring the static sag push the rear and let it extend slowly, then measure.

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I have the 2010 yz450 and they say on these late model bikes that a sag of 98mm to 102 is reasonable and to have no more than 25mm or less of static.

Like the bike is (stock) I used my sag scale and marked a place on the number plate and set the scale at Zero. When I sat on the bike and had my friend to see where it went to it was 102mm and then we measured the static and it was 38mm.

I thought the shock felt stiff to me this past sunday at the track. It felt like it didnt want to squat any and it just wanted to stand up around turns and not soak up in the turn. Also when jumping this triple jump, when I landed it felt kinda hard.

The forks were stiff also and made my wrists hurt when landing off of big jumps. I could feel the ground through the grips.

Do I need to turn my shock counterclockwise (lengthing the spring) to make it a little softer in the rear? (but that would give me a smaller sag reading wouldnt it?)

Or do I need to turn the shock clockwise(shorting the spring)(more tension)

and make my static sag more toward the 25mm range?

I guess what I'm asking is ........ How do I get around 25mm static sag and have a race sag of 98mm-100mm

It's 38mm but I didnt push down (I dont think) after i took it off the stand.

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Should be OK. As mog said the shock will take a while to settle down. Try to open the high speed a little and one click from reb. Test test and more test

Jusa

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Being as the bike is so new, and to some extent even with an old bike, you're going to want to watch out for "stiction". That's the tendency for the friction in the linkage seals and shock shaft to hold the bike either artificially up or down from it's true static sag.

To check for it, take the bike off the stand, push down on the seat, and let it return slowly to it's static height. Measure. Then, lift the fender and let the bike back down to it's static height slowly. Measure again. There may be as much as 15mm difference in a brand new unit. The true static sag would be midway between those measurements, so if you got 38mm after pushing down, and 28 after lifting up, the true number would be 33.

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Being as the bike is so new, and to some extent even with an old bike, you're going to want to watch out for "stiction". That's the tendency for the friction in the linkage seals and shock shaft to hold the bike either artificially up or down from it's true static sag.

To check for it, take the bike off the stand, push down on the seat, and let it return slowly to it's static height. Measure. Then, lift the fender and let the bike back down to it's static height slowly. Measure again. There may be as much as 15mm difference in a brand new unit. The true static sag would be midway between those measurements, so if you got 38mm after pushing down, and 28 after lifting up, the true number would be 33.

I'll do that!

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Thanks Gray, that's what I needed. I did not think about the stiction. and to average the two. :thumbsup:

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Being as the bike is so new, and to some extent even with an old bike, you're going to want to watch out for "stiction". That's the tendency for the friction in the linkage seals and shock shaft to hold the bike either artificially up or down from it's true static sag.

To check for it, take the bike off the stand, push down on the seat, and let it return slowly to it's static height. Measure. Then, lift the fender and let the bike back down to it's static height slowly. Measure again. There may be as much as 15mm difference in a brand new unit. The true static sag would be midway between those measurements, so if you got 38mm after pushing down, and 28 after lifting up, the true number would be 33.

As you know my original race sag when the bike was new and had never been ridden was 102mm and 38mm static sag. I then rode the bike at the track last sunday for and hour and twenty minutes of riding time.

I remeasured the race sag awhile ago and it had fell to 100mm and a static sag of 40mm. I guess after the bike was ridden it kinda loosened up the suspension some.

So I wanted to reset my race sag and try to get it somewhat in the area of what they want the static sag to be and that is no more than 25mm.

So I turned the spring on the shock counter clockwise(where the spring went up the shock body) two full turns. and that gave me a race sag of 104mm and a static sag of 46mm.

The reason i increased my race sag was because I wanted the rear shock to be a little more soft so when I went around turns it would squat some and soak up a bit more on large jumps to where when you landed it wouldnt jar you as bad.

I checked for stiction with this 104mm race sag and 46mm static and found that when I lifted the rear fender and let the suspension settle back own its own I got 40mm so I guess the the true static is 43mm.

Does this spring sound like it will suit me at 197lbs(this is with riding gear on)?

I should be at the right weight for this bike cause I'm not over weight nor am I under weight.

i cant figure out how to get more with in the range of the static sag of 25mm.

Do I need to decrease my race sag by moving the spring down the shock body by putting tension on it? If so would a race sag of "say" 90mm be to little?

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You can get your sag numbers to 25mm an 100mm with softer spring. I think you can achieve better results with std spring and sag numbers around 35mm / 100mm. Always measure your sag when shock is cold. Your manual says to run 90-100 race sag. Minimum preload 1,5mm and max preload 18mm. 103 race sag is not a bad thing in sandy conditions.

std high speed 1.25, lc 8 and reb 14. Try these settings hc 1.5, lc 8 reb 15-16.

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The reason i increased my race sag was because I wanted the rear shock to be a little more soft so when I went around turns it would squat some and soak up a bit more on large jumps to where when you landed it wouldnt jar you as bad.

Try to get this:

Sag, no matter how you set it, has no effect on how hard or soft the suspension is at all. None.

All the sag does is set the height that the suspension sits at when loaded. The spring stays just as stiff or soft no matter how it's set.

If the bike is too stiff, you need either a softer spring, or you need to change your damping settings.

The race/static sag "rule", such as it is, is intended to give you an indication of how nearly correct the spring rate is, and by the old rule, yours looks too stiff as it currently is. But I'd wait for the recommendation of a professional tuner, as I have seen examples of other bikes where the 100/25 rule did not seem to apply.

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