I just changed the fork seals on my '83 750E. When reassembling the forks, the manual didn't indicate which way to install the tapered damping valve piece that fits in the bottom of the fork slider. I installed it with the narrow end up, as it seemed that it should fit inside of the slider and close it off. It fits the other way, too - but it just seemed to go the way that I installed it. On the first leg, I didn't pay enough attention to the disassembly to see which way it came out, but it wouldn't have helped - it all just dumps out of the leg after you jerk the slider out to pop the teflon bushing from the top of the tube, leaving you with a small handful of miscellaneous parts to dump out when you pour the rest of the oil out.
Everything went back together well, but when I topped the legs off with oil, they both took FAR more than the volume of oil listed in the shop manual (304cc, I believe). They took roughly 450cc each to get the level up to 170mm from the top (the book gives a volume vs. measurement either/or listing).
After reassembling the forks and remounting them to the bike, I filled them in place with the springs removed, and no weight on the forks - as I had done before during a fork oil change. The only thing I did differently this time was to bounce the fork legs a little bit to get any air bubbles out and let the oil settle. Well, it kept settling, and settling - I had to top it off a couple of times. The way I took the oil measurement was with a large veterinary nursing syringe - I installed a length of tubing so the total length was 170mm, then topped off the fork leg and used the syringe to suck out the excess oil.
But now I have a problem - the front end has almost no play at all. If I grab the front brake and try to compress the forks, they give about an inch - but no more. And they're near rock-hard.
My guess is that I've over-filled the legs (even though the oil level is where it should be by measurement, but the volume of oil is too high), or I've installed the damping valve backwards. Is the oil level supposed to be measured with the fork legs off of the bike and the sliders fully compressed? I've done fork seals on other bikes before, and have always refilled them on the bike with the bike jacked up so there is no weight on the front end (sliders fully extended).
Any advice would be GREATLY appreciated, especially before I tear the forks apart again and risk damaging the new seals. I'm supposed to go on a ride next saturday with my local group, and I'd like to make this one after having the bike apart for the last month or more.
Thanks in advance,
-Q!
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