After purchasing the 87'. The forks were pretty much non functioning. They had the RPM valves installed, but just did not work. I contacted Randy at RPM to diagnose the problems. After the conversation, we determined that the best course of action was to send the forks to RPM. Randy found a few problems, Mainly One fork leg would not compress at all and the other barely compressed, the oil had congealed and clogged up the valves, and some other worn out parts.
Randy replaced the worn out bushings, cleaned the valves, reassembled the forks and replaced the fork seals and sent them back.
After just a very short ride, I am extremely impressed with the transformation of the forks. A huge Thank You goes out to Randy at RPM.
Fred
Quote from: aviationfred on November 28, 2013, 09:53:02 AM
After purchasing the 87'. The forks were pretty much non functioning. They had the RPM valves installed, but just did not work. I contacted Randy at RPM to diagnose the problems. After the conversation, we determined that the best course of action was to send the forks to RPM. Randy found a few problems, Mainly One fork leg would not compress at all and the other barely compressed, the oil had congealed and clogged up the valves, and some other worn out parts.
Randy replaced the worn out bushings, cleaned the valves, reassembled the forks and replaced the fork seals and sent them back.
After just a very short ride, I am extremely impressed with the transformation of the forks. A huge Thank You goes out to Randy at RPM.
Fred
I would like to mention that I "flushed" and changed my fork oil a couple of times in the last 2 years. For "flushing" I would use about a qt of old dot 3 brake fluid and did all I could to get the tubes clean then I would put the new fork oil in. This summer I pulled the forks out and totally disassembled them and was surprised at the crap way down in the bottom of the lowers (vases). I still think "flushing" is good but I would recommend when you change fork seals (or upgrade to aftermarket fluid control valves) to go the extra step and totally disassemble the forks and do a good cleaning. Just an opinion and my experience.
George
George,
Why your choice of brake fluid as cleaner?
I've used kero before with good results.
Arnie
Quote from: Arnie on November 28, 2013, 06:52:13 PM
George,
Why your choice of brake fluid as cleaner?
I've used kero before with good results.
Arnie
I was wondering the same thing. I use diesel, then flush with hot soapy water and rinse with clean hot water. Blow dry with compressed air and re-assemble. Pete.
Quote from: Arnie on November 28, 2013, 06:52:13 PM
I've used kero before with good results.
Arnie
I've been using charcoal lighter fluid, and it works very well.
Yep, you gotta install them right with the right spring rate and the right oil and then they work really RIGHT.
Just like the RPM fork brace, i'm not giving either of them back.
Andy
Quote from: Arnie on November 28, 2013, 06:52:13 PM
George,
Why your choice of brake fluid as cleaner?
I've used Kero before with good results.
Arnie
My choice was because I looked into my cabinet of chemicals and paints and that's was in front. It was opened bottle from a previous repair over a year or two ago and I wouldn't use it in any brake application now anyhow. It needed to be disposed and I could see no harm in using it. It actually worked pretty good. Kero would probable be better for it's solvent value. I will use it next time :good2: Clean oil is good oil....
Did you ever think how archaic fork design is in these bikes ?
George
This whole refurbishment think I'm doing to my bike is getting to be more like work. I think about a book that I've read called "Zen and the art of motorcycle maintenance". Even though the book had very little to do with bike maintenance, it helps to just say to myself "the art of motorcycle maintenance". It helps.
I drove my bike a little, probably 5-600 miles before I tore it down. There was something -not good happening with the forks. I'm not going to deal with it now. I'll save that for some summer sunday when all is well. It's good for me to read your post on the subject and file it in the back of my mind and that is a little closer to what the book was about. Cheers joe
Ah, not all was well with my forks either. Did a complete rebuild with all of Randy's toys, and what a hell of a difference! It goes exactly where I think it now, not just the general direction. I'd suggest a winter rebuild would make a nice, relaxing exercise. (My only thing is wondering if we picked one-level too stiff of fork spring.) Dive in, grasshopper!
:empathy: