So how many of you guy have spent time messing the the FXDX adjustable forks?

I found that initially, the spring were way too soft. At one time I added another inch of preload which helped (2000 FXDX, I weight about 185-190). I pretty much left the compression and rebound adjustments as the were. That helped a bit but I still bottomed a bit. I used 10 wt oil. I later did the compression gold valve and went with the Racetech recommended spring. When I ran the web tool for the gold valve kit I got that I should use 0.9 kg/mm springs and they gave me a shim-stack for the valve. They said to use USFO 10 fork oil, FRSP2938 (0.9kg/mm) springs, C35 shim stack. 6 clicks compression 4 clicks rebound.. I later found out that the USFO 10 oil was closer to 5 wt oils and I used 10 wt spectro.. Forks were stiff but seemed to work well. I eventually added a zip tie to the forks to measure travel, and found that on a 100 mile ride I was using a little over 4 inches of travel. Total travel on these are about 5.75 inches if all the way into the physical stop. With the hydraulic stop, I'd guess usable travel to be about 1/2 inch shorter so say 5.25 inches. So.. Springs too stiff. I went back to the Racetech website and now they say use 0.785s with a different spring FRSP S3033(xxx).

I've changed to 5wt oil and noticed very little in high speed damping change except that the low speed adjustments could use a smaller setting to achieve the same low speed performance. The forks were still stiff but may picked up a couple tenths of travel on an average ride. About ready to blow come money on lighter springs..

What are you other guys using for tuning the front forks.

 

Hi Max,
Just a thought... In the grand compromise between brake dive and travel, I would ask, do you like the braking performance as is. I prefer a stiffer spring as it holds the front end higher under hard braking, but that's a personal preference. Having an inch of unused travel is like money in the bank for that bottomless pothole with your name on it.
That being said, have you tried a click or two less on compression damping as this would allow a bit more travel to be used in everyday conditions? Knowing your level of skill, I know your sag is set correctly, but oil level has a direct affect on how the forks behave, a lower oil level will reduce the "air spring" effect and also allow a bit more travel to be used as you won't be compressing as much air, by the same token brake dive will increase.

: Mike

 

I know nothing, but I enjoy learning. Subscribing.

 

 

Never messed w/ adjustables on a sled..., do have them on the MXs

So an expert on what you're asking..., I'm not



That said - 1" added pre load - all at once - is quite a bit..., typically I'll go up / down - in 1/4" increments till I get the feel I want

Bet you could reduce the spacer and get back more travel / soften it up

===================

Here's my suggestion

Compression / rebound adjusters are for fine tuning..., close tuning is achieved w/ spacer length

And because you stated it started off soft - then went to the hard side w/ the added 1" spacer

Leave the fine tuning alone for now..., and until you get it close

Cut three more sets of spacers 1/4"..., 1/2"...., and 3/4" shorter that what you have now (PVC is cheap)

Test each of those - again while leaving the current compression / rebound where they are

=============

My crystal ball says - 1/4" to 1/2" shorter will get you in the ball park

Hell for that matter you could go 1/8" spacer increment for even finer tuning

Ghost

 

Brake dive was really only noticeable when the the bike had stock strings. I should have mentioned that I have a way to measure springs and the stock ones came in at 0.61 kg/mm.. The 0.9 springs come is at 0.88 using the same methods.. Looking the spring rates forks lost a lot of brake dive when going to the 0.9s..

I've tried adding 4 clicks on the compression valving. I've tried adding 4 clicks over recommended 4/6 on both then 8 clicks on both compression and rebound.. Have done this with both 20 wt and 10 wt in the forks. At almost max opening, the forks start to feel a little mushy but I'm still not using all travel. I've been setting the oil at a lower level when I changed from 20 to 10.. Didn't seem to make much difference. I originally had the sag set to 25% but released all the preload and got to about 30%. That did help a little.

I thinking to order 0.8s and give them a try..

 

This is good stuff. As the forks are adjustable for preload, decreasing did help (about 3/8 inch) but based on the changes in recommended spring rate from the calculator at racetech, I think I'll change rates next.. The damping adjustments really don't do much and I suspect that it's because the spring rate is too high that the damping adjustments don't have much effect..

 

Hi Max
Sounds like the way to go, with what you have posted above I agree with you, you're a bit to stiff and a spring change will help
I'm running Works cartridges with triple rate springs in 49mm forks with an inch of additional preload, and Speed Merchant preload adjusters. 12 ounces of 7 wt. Bel Ray oil per leg, and 25% sag. With this setup rebound damping is adjusted with oil weight, compression damping can be adjusted by returning the cartridge to Works, spring rate can be adjusted by adjusting the crossover spacer engagement height. Under maximum effort braking I compress about 2 inches, general riding about 3 inches not counting sag, so I also have about an inch of "reserve" travel.
I have about a thousand miles on this set up and the suspension is just starting to break in, the only changes planned is 16 ounces of oil in each leg to try to get less braking dive, if that doesn't work then possibly a spring crossover adjustment.

Have A Great Holiday: Mike

 

I figure that the spring change will bring the shock to a point where the forks adjustment work better. I can still soften the high speed compression by pulling the pulling compression spring shims out of the gold valve. I have a set of 0.85 springs so if the 0.80s are too soft I can go to them.. They are in another set off forks so I can't pull them unless I have something to replace them.

It would be interesting to plot spring movement versus pressure on your works spring setup and figure out how the rates change with spacers.. Could probably do the calcs in excel.. I like and use works shocks but they tend to be a little on the stiff side tho they handle harsh bumps real well.. I was wondering if the Works fork cartridges used similar valving as the rear shocks.

Not sure I like 3 spring rates as it would seem to me that most forks with good damping only use single rate.. I seem to remember Works going from 3 to 2 one one of their cartridge kits tho it might have been the Bagger kit.

Back at you on the holiday..

 

Max,
Just curious if you happened to call RaceTech to speak to someone?
When it was time to order up my DX springs, I called and spoke to Louie. He was very helpful and seemed to know his stuff.
I have a '01 FXDX-T and the recommended spring on the website was quite different than the one Louie told me I needed.
Will post exactly what I received tomorrow night.
Haven't installed it but plan to tackle it this weekend, if time permits.
-G

edit: also 185-190lbs, so should be pretty similar.