I looked these up because I haven't thought about it in awhile and wanted to refresh my memory. Someone will have to double check my math because I'm getting old.

I rounded up or down to whole numbers.


'06-'07
Front: 11.2 inches = 284mm 1/3 = 95mm 10% = 28mm
Rear: 11.0 inches = 280mm 1/3 = 93mm 10% = 28mm

'09+
Front: 10.2 inches = 259mm 1/3 = 86mm 10% = 26mm
Rear: 9.1 inches = 231mm 1/3 = 77mm 10% = 23mm

 

Thanks. Is the 10% an acceptable variation either way?

 

10% referred to IDRIDR's post about static sag.. 10% of total travel

Here is how I understand the process...

- Measure bike on a stand with swing arm fully extended (Measurement one)
-Put bike on the floor and mount in your normal riding gear in your normal riding position (helps to have someone to hold the bike and someone to measure) , then measure in the same spot = (Measurement 2)
-get off the bike, hold bike upright and bounce the seat a couple times, measure in the same spot again = (Measurement 3)

(Measurement one) minus (Measurement 2) = Race sag, You're looking for roughly 1/3 of your total travel (adjust with spring preload)
(Measurement one) minus (Measurement 3) = Static sag, You're looking for roughly 10% of your total travel

You adjust Race sag with spring preload.
If you get your Race sag right, but then you don't have enough Static sag, you need a heavier spring. (You had to put in too much preload to get correct Race sag.)
If you get your Race sag right, but now you have too much Static sag, you can use a lighter spring.


So, on the rear of my '09, I want to shoot for around 77mm sag when I'm on the bike, and about 23mm of sag under the bike's own weight.

 

Thanks