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Discussion Starter #1
Kind of a curiosity question since the reason doesn't have to matter:

When you look up the setup info for the forks for a 916 the Racetech.com site makes a point of stating that the fork oil level should be measured with the springs in....whereas the forks on my '05 GSXR are to be measured with the springs out. The internals on the two forks are almost identical, so why do think there is that difference? I just find that bizarre....
 

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You should measure with the springs in. A stiffer springs should have more material which means less volume available for fluid or air. Yes, spring material (density), design, temper, etc can all impact this, but I digress. The amount of fluid really doesn't matter (obviously within reason) since it's essentially incompressible. The remaining volume for air is what changes the fork's characteristics, so that's what you need to keep constant, unless making such changes to intentionally modify its properties.
 

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You should measure with the springs in. A stiffer springs should have more material which means less volume available for fluid or air. Yes, spring material (density), design, temper, etc can all impact this, but I digress. The amount of fluid really doesn't matter (obviously within reason) since it's essentially incompressible. The remaining volume for air is what changes the fork's characteristics, so that's what you need to keep constant, unless making such changes to intentionally modify its properties.
Sweet! Wanna come over to help do the 888's forks? :D
 

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Discussion Starter #5
nearly every spec for a showa i've seen is springs out. quite a lot of the ohlins are spec'd spring in, not 1198 ones from memory. it's just a convention.
Try using the Race Tech Suspension site's spring rate calculator and it specifically states to measure oil level with the springs in. All the other bikes that I entered into the "calculator" don't say that, and all the web searches seem to imply that springs-out is the most common way to measure. I have Racetech gold valves so I am using their setup info as a guide.

I was just curious if there was a reasonable explanation for not taking into account the change in volume of new springs (like nine16 states) with one model of fork but not with others.
 

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You should measure with the springs in. A stiffer springs should have more material which means less volume available for fluid or air. Yes, spring material (density), design, temper, etc can all impact this, but I digress. The amount of fluid really doesn't matter (obviously within reason) since it's essentially incompressible. The remaining volume for air is what changes the fork's characteristics, so that's what you need to keep constant, unless making such changes to intentionally modify its properties.
:yeah:
 
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