Fork Oil change question

[blkbrdrydr]

I'm in the process of changing my fork oil while installing new springs and I have a couple of questions:

If I pour in the recommended amount of fork oil to begin with... why do I have to remove so damn much in order to get to the proper 143mm level from the top of the fork pipe when everything is fully compressed?

I connected a small tube to a metal ruler so that I would siphon out everything above that level and I sucked several syringes worth of fork oil out before I got to the recommended level

When I went to do the 2nd fork tube, I couldn't remove the bottom drain bolt. It just turned, and turned, and turned. Finally, I gave up and tightened it. Of course... that went perfectly and was easily torqued to 14lbs but... now I don't have any thread locker on the damn bolt.

Why did the damper turn with the bolt on one side and not on the other? Why was I able to tighten it back in but not remove it?

Thanks,

[SwampNut]

The bolt didn't come out because there was nothing to hold the internals. You got lucky on the other one. I use an air impact for this job, that's the easy way. The alternative is to push a shovel handle into the fork and have someone push on it while you remove the bolt. You could also try removing the bolt before removing the caps and springs.

On the oil level, it sounds like either you didn't remove all the old oil or you didn't burp the forks properly. Did you do this on or off the bike? If on the bike, did you pump them a lot while allowing them to drain, and repeat that a few times? If not, you didn't get all the oil out. Actually even then you would not get it all out.

After putting in new oil, did you burb the internals by working BOTH the fork leg 10 times (minimum) and the damper rod? If not, then you had air, and now your level is wrong.

[SwampNut]

Actually, now that I think about it, the shovel handle trick may not be good on our style of fork. Leaving the springs in may be the only alternative. Or cutting a piece of PVC pipe so you can use a fork cap to push on it. But air tools are the "correct" and easy way...