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2010 YZ450F suspention question

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Just bought a YZF450 2010. When I checked the sag I found it was 101mm does that mean the spring rate is right for my body weight???

It feels a bit soft, but maybe that is the way it is supposed to be, my other bike is from 04. I think I bottomed out the forks on a bad table top landing. felt kinda hard.

I weigh 84kg with gear on, last time I checked.

I have to say I get very little arm pump on this bike.

I will re-check the sag again tomorrow, it might be more after break in.

Any input would be appreciated.

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Just bought a YZF450 2010. When I checked the sag I found it was 101mm does that mean the spring rate is right for my body weight???

It feels a bit soft, but maybe that is the way it is supposed to be, my other bike is from 04. I think I bottomed out the forks on a bad table top landing. felt kinda hard.

I weigh 84kg with gear on, last time I checked.

I have to say I get very little arm pump on this bike.

I will re-check the sag again tomorrow, it might be more after break in.

Any input would be appreciated.

Everything that you need to know about initial spring selection is a function of sag to pre-load.

In other words, how much pre-load has to be applied to a given spring to achieve a given level of sag?

Ideally, we shot for a preload of about 8 to 12mm for about 100 to 105mm of sag (bike and rider).

Anything outside of this pre-load range usually means that you are outside of the operating parameters of the spring.

And certainly anything more than 20mm of pre-load on the spring and the spring will begin to destroy itself...for most shock spring.

This is why springs usually have a "maximum deflection rating" associated with them, which is different than "the compressed length".

:thumbsup:

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Eah ok,

so by pre load you mean. The amount of mm the adjuster nut is screwed down, from the beginning of the thread to the top of the adjuster nut on the shock? I only have about an hour of riding on the bike, and not too hard as I was running the motor in.

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Eah ok,

so by pre load you mean. The amount of mm the adjuster nut is screwed down, from the beginning of the thread to the top of the adjuster nut on the shock? I only have about an hour of riding on the bike, and not too hard as I was running the motor in.

Yes.

The free length is the length of the spring as if it was not installed on the bike.

The installed length, or pre-load length, is the length of the spring as measured on the shock, with the bike on the stand.

This will be a lot more helpful and beneficial then considering what the bike does or doesn’t do without the rider.

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Where would I find the actual length of the sring without taking it off the bike?

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Where would I find the actual length of the sring without taking it off the bike?

It's a KYB 50/16 spring so all of them should be 64x92x260mm. :banana:

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You could go to racetech.com and see what there spring calculations come up with for your weight and type of riding.

Intersting to learn about the overall length vs. preload mm's for 100-105 mm's of race sag. I think I may look into mine. Thanks.

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So I guess I am with in the 8-12mm

Spring length 260mm

Fitted length 252mm

Sag 101mm

Sorry but, whats static sag???

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When the bike is on the stand, measure from center of axel to the fender (A) and then take the bike down from the stand...push the rear once and let it extend slowly on its own...measure again (:banana: ....=>A-B=static sag

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