Topic: Front fork fill

[chrisf]

Hi All:

I finally got around to changing the oil in my forks. 35 year old oild is some interesting, stinky stuff. Anyway, I filled the back up with 200cc's of oil (I hope this is right because the Honda manual is pretty confusing in this area). To move the oil around, I left the upper sealing bolts off and moved the lower fork up and down. Now, when I sealed them up, I still hear a squishing sound when I move the forks up and down.

I now think that I introduced too much air into the damper, or is this normal and goes away with riding?

--Thanks, Chris

[Jonesy]

You did the right thing by pumping the forks a few times to get the excess air out of the lower portion, where the oil does the dampening. The noise is from the oil being pumped through the small orifices in the fork pistons. This is how the dampening is accomplished. My bikes do it too, with fresh oil and rebuilt forks.

[CBGBs]

 Yeah, Chris I think your alright there. 200cc sounds just right. So what wieght and oil did you use? AT?

[crazypj]

The damper is at the bottom of fork leg so any air will be at top eventually.
 The 'piston seal' on damper rod doesn totally seal so any air migrates to highest point.
 Its still a good idea to work forks through their travel though
 I gave up on oil quantities years ago.
 Better to get an oil level gauge and set fork oil level instead.
( I use a big syringe with a piece of stainless steel tube)
Between 6" to 7" from top, springs out, fork compressed.
Higher levels increase spring rate at end of travel (the air gets compressed and acts as spring)
Its the way motocross bikes have been done for decades.
Bit of a pain when you have to remove bars first but worth it to fine tune forks to your riding style
PJ