Yet Another Fork Valving Source

[FJ1100mjk]

RPM Racing, Race Tech, and what I am having sent to me...

http://www.yssusa.com/products_yss_pdforkvalve.html

$135 USD / pair

[movenon]

RPM Racing, Race Tech, Ricor, and what I am having sent to me...

http://www.yssusa.com/products_yss_pdforkvalve.html

$135 USD / pair

Here is what I use .. http://www.motoparthub.com/24_0361_VTwin_41mm_Fork_Damper_Valve

Here is some more info on them. Not an FJ write up but the same valve... http://www.svrider.com/forum/showthread.php?t=112643

I did some slight modification by making an "adapter" for a good seal out of CPVC for less than 10.00.
George

[Country Joe]

As long as you are capable of tuning these valves and can get a variety of shims for them  that's cheap!

[movenon]

Here is a guide to tune the "RT" style of valves. No shims or other springs required for mine. Just adjusted the spring tension with the adjust nut.

http://www.racetech.com/page/title/Emulator%20Tuning%20Guide

Mine had a large range of adjustment. At 4 turns it was way to hard/firm and at 1 1/2 turns it was to soft.  From memory I ended up at 1 3/4 to 2 turns. Running 10-30 synthetic Mobile 1 for fork oil.  For me my front end is perfect.

It is so good that now I can feel the short comings in the rear shock. That's an adjustment project for this summer..
George

[FJ1100mjk]

^^^

George:

Tell me/us a little more about your front end set up.

1. Oil level in the forks?

2. Spring rate, and brand of springs?

3. Preload spacer length?

4. You're weight w/o gear on, and how you derived the spring rate (Race Tech or Sonic Springs calculator?)?

5. Why Mobil 1 variable weight oil?

6. Static sag on front end?

Thanks!

[movenon]

^^^

George:

Tell me/us a little more about your front end set up.

1. Oil level in the forks?

2. Spring rate, and brand of springs?

3. Preload spacer length?

4. You're weight w/o gear on, and how you derived the spring rate (Race Tech or Sonic Springs calculator?)?

5. Why Mobil 1 variable weight oil?

6. Static sag on front end?

Thanks!

Some spec's:
Bike 1990 FJ

I weight 220-230.  The Race Tech spring calculator recommended 1.0 kg .  I got a good deal on some new .95kg springs for 75 bucks so that's what I installed. The emulators  (Damper Valves as they are referred to on Harley sites)  are less than 50.00 for both. 

Oil level from memory 130mm down from the top of the tube with the springs out and forks collapsed.

Preload set at 15mm.   

The Race Tech PVC spacer was 45mm long BUT that's with the adapter I made that sits on top of the FJ dampener tube and the emulator sits on top of that.  FJ dampener valve was set to full open and dampener drilled open just like installing an RT Gold valve.  A picture might help. The picture shows one end of the CPVC adapter with a reducer just on one end. On the final adapters,  I installed a CPVC reducer to both ends of the adapter just because.



CPVC adapter details. CPVC (cold water PVC) parts were from Home Depot. 1" slice and 2 reducers, 1" to 3/4".  After gluing together I sanded off the embossed lettering on the reducers with 400 grit on a flat surface. Next take some sand paper and dress down the "adapter spacer" diameter until it falls down the fork tube under its own weight.  Not much sanding required.  Next open up the diameter on one end of the "adapter spacers" so the emulators fits in snug to loose. Not critical. I used a Dermal with a small sanding drum.  It is all self explanatory with the parts in front of you.



The adapter was made because I wanted the emulator to sit on different surface other that the sharp edge of the FJ damper tube and to fit more precisely.

On preload for the 88-90's there are 3,  5mm adjustment steps. On mine at the lightest setting I am at 15mm preload.  Second position is 20mm and third 25mm.  I run on the second step.  23mm free SAG and a total of 50mm SAG under load.  Forks are set to use about 5.8 inch's of travel before it hits the triple clamp. The hardest wheel hit I have had it still didn't bottom out and I had about 30 more mm before it would have hit.  That was an intentional hard hit to measure it.  I leave 2 wire ties around the fork tubes at all times.  Push them down to the top of the fork seal.  The ties will stay up at the top of the travel on the fork tube and serve as a marker.  One side I reset often,  the other I leave as a maximum travel marker.

Mobile-1 because that was on the shelf in the shop also wanted to use an easy to get fluid.  15 weight fork oil would also be a good starting point. I don't race or ride that hard so foaming and etc. is not a player for me.  Also for what ever it is worth the Yamaha service manual tell's me I can use that weight also. As it turned out I am happy with it.

Tip:  If you don't have one think about getting one of these http://www.homedepot.com/p/GrabEasy-Grabber-and-Retriever-PF0401/202505170 Makes it easier to grab out the emulators when you want to adjust them. 6.00 item.

Anyhow that's what I use. My thought was if the HD dampners (emulators) didn't work out I could always but some RT units. Just an option anyhow.
George