Some of you may know that my fork seals were blown out from the Colorado Rally this year and I have never had the forks apart on ANY bike, but I was willing to give it a go and learn something along the way.
Initially, I was just going to replace the seals and bushings, but I talked myself into getting the Fork valves and R-T springs from Randy @ RPM while I was in there.
With Randy's help and advice, I installed the .80 springs.
Randy also told me about his damper rod holding tool, so I made one of my own out of a nut measuring the required 27mm across, and welded a piece of re-rod into the nut and added a t-handle to the top of it.
Along with that and a 10mm, 3/8 drive socket on my impact, the removal and install of the damper rod couldn't have been easier.
Figuring out the amount of preload I was looking for went like this,
With the valves and springs installed and the inner fork tube fully extended, I took the measurement from the top of the spring to the very top of the inner tube, which was 183mm.
Then with the fork cap set on the second detent, I measured it at 53 mm.
Take that away from the 183, and that gives me 130mm spacer length, which would put the forks at (0) preload.
I then added 20mm to that which brought it back up to 150mm, and this was the length I cut my spacers at.
Installed them as instructed and put the rest of the bike back together for the test ride.
Now the ride was something I know some of you have read about from others here, but until you try it out for yourself, you'll never appreciate the huge improvements that it makes to the old' FJ.
My ride started of by getting right up to speed leaving my driveway and I noticed right off, that the bike was super easy to turn-in on corners.
I wasn't expecting this!!
But I love it!
The front end also soaks up rough road like it you were riding on a pool table...VERY smooth and controllable at any speed.
And now, like others, the rear feels like a slap on the ass, compared to how nice the front is working.
My thanks to Randy and all he does for all of us with RPM.
Top notch fella!
Your new rear shock is next on my list, can't wait.
Now I need the new rear tire mounted and get my new chain and sprockets on!
Leon
Way to go Leon!
Glad you decided to go with the fork valves........Once you get the forks apart, and see how they work, it's not that difficult a project.
I know what you mean about the rear shock.
Riding this year during the Colorado rally, I could tell the front end felt nice and solid, and the rear end felt wishy-washy. My tired rear shock is adjusted all the way to max, and it certainly doesn't have the control I would like.
I wish Randy's valves were available 2 years ago, when I decided to do my front forks. I went with the racetech valves, and 1.05 springs(I'm heavier), but so far, I'm happy with those.
Any idea when Randy's rear shock for '90 model will be available? and approx cost?
No word on the rear shock as of yet, Alan.
The RPM Fork valves are designed to use a lighter spring.
I actually had ordered the .90 springs, but talked with Randy before he sent my order, and he suggested I go a little lighter on the springs to allow the fork valve to work as designed, instead of being bound up to tight.
This is based on his on-going feedback he is getting from riders current using these valves.
He said he's still working on the recommendations for the correct weight of spring based on rider weight, combined with any gear the bike is loaded with.
I'm about 220 and rarely have any extra gear on the bike, so based on that, Randy recommended the .80 springs.
And from my inital impressions, I think Randy hit it pretty damn close.
The spacer length can also be used as a tuning tool, by either making it longer or shorter.
Congratulations Leon,
Your experience is what I experienced as well, including the softer spring rates.
And I am also waiting for a rear shock.
Randy & RPM really do a lot for FJ owners.
And based on our one day of riding together in Gunnison, Randy thought my riding was acceptable...
Well, I suppose I'm in for it now...
Keep up the good humor,
Mike Ramos.
Quote from: 1tinindian on June 30, 2012, 09:03:53 PM
Figuring out the amount of preload I was looking for went like this,
With the valves and springs installed and the inner fork tube fully extended, I took the measurement from the top of the spring to the very top of the inner tube, which was 183mm.
Then with the fork cap set on the second detent, I measured it at 53 mm.
Take that away from the 183, and that gives me 130mm spacer length, which would put the forks at (0) preload.
I then added 20mm to that which brought it back up to 150mm, and this was the length I cut my spacers at.
Installed them as instructed and put the rest of the bike back together for the test ride.
Leon
Couple of questions, how did you work out that these figures would give you zero preload?
Where did you get the figure of 20mm to add on from?
Cheers
183mm from teh top of the spring to top of the fork tube. 53mm from where the top cap tightens on the fork tube, down to where the spring preload surface is. Screw the top cap into the fork and you'll have a 183mm-53mm (130mm) gap.
Add 20mm to the spacer (now at 150mm) to get the desired initial preload.
DavidR.
Quote from: nurse on October 23, 2012, 01:27:19 PM
1) Couple of questions, how did you work out that these figures would give you zero preload?
2)Where did you get the figure of 20mm to add on from?
#1) Already answered by David
#2) That is then spring manufactures recommended preload of the spring.
All those questions will also be addressed in the installation instructions included with the valves & springs.
Randy - RPM
I think i got it now!
Cheers folks
:good:
Leon thanks for the update and feedback on the fork valves and springs.
Kurt