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Both of my fork seals are leaking. Does everyone just recommend get the OEM oil and dust seals? or is there an aftermarket one that works as well or better?

The guy I bought it off of said it had racetech internals (not sure if it is just springs or the valving as well). If it is valving, any idea of fork oil level and weigth to use? Thanks.

I used OEM seals. Worked fine. IF they had lasted only a riding season, guess I would've looked for something else. They lasted for years.

Re: 'If it is valving...' ??

Doesn't matter. Opinions/preferences vary on viscosity and height. I used Mobil-1 ATF (5w..or whatever it is)..and liked 110mm a whole lot better'n 100mm. Never got around to trying 115/120mm on the OEM forks.

One last question, I usually order from Ron Ayers and that takes nearly 2 weeks. Should I go ahead and get both bushings for $46 more or just wait and see what shape they are in first? Thanks.

My personal experience and all that disclaimer junk...but...

I had the bushings in hand (AND seals AND dust caps AND seal driver) before I started the job. My forks didn't come apart for diddle. By the time I got done slide-hammering the pee-wah out of 'em (yes...I'm familiar with the process, the idea of 'tapping' them..I've taken other forks apart without any trouble), the bushings were shot..screwed...blued...tattooed...beat up...ruined...

..BAD even.

I was glad I had 'the stuff' to put 'em back together.

**Your mileage may vary**

So I put in the new fork seals today. It looked like the Racetech valving was installed. However I think the springs may be stock. They were 472mm long and the metal spacer was 90mm. The measurement from top of spring to bottom of top cap without spacer (but with the two washer things) was 63mm so I guess that means a preload of 27mm? I thought the suspension felt pretty good before. I am going back with 5wt oil and 110mm oil level. I know everyone seems to change to XR springs and cut their own spacer. What kind of improvement does this give? Thanks.

Stock springs run around 470mm..but the length of them doesn't have anything to do with with the spring rate is.

Racetech valving (gold valves) is night and day difference compared to the OEM piston/shim setup. There is no possibility of wondering which is which.

Someone could have put a gold valve kit in and left the springs as they were. That would be a bit bass-ackwards of an approach...unless the PO weighed in at 130lbs or so.

Yep. The stock spacers are 90mm and OEM preload is around 30mm.

Never have understood the point of that.

Improvement? Correct rate springs in your forks is a 'modification' that rates up in the top of 'the best' things to do to a dirtbike. That the XR springs are longer? If the 90mm spacer is such a great idea, why not run 400mm springs and a 115mm spacer?

Springs are part of a working suspension. Steel tube in place of springs ain't.

Yeah, it definitely had the racetech gold valve. The guy that installed it must not have but locktite on the nut because when I took out the valve assembly on the bottom, all of the shims and the piston came out in pieces. Fortunatley nothing was damaged. I looked through the Racetech documentation and put the shim stack according to my weight and style (the one time use code in the instructions the guy I bought it off of worked on Race-tech, he must have just guessed at what shims to use). I went back with what I assume to be the stock springs and spacer. I will probably add XR springs soon. Racetech recommends .350kg/mm springs for my weight and says stock is .42kg/mm. Of course mine could be Racetech springs since I have heard they are short like the stock ones. But there is nothing written or stamped on them.

..shims and piston out in pieces.. Now that's a revalve job!! :snicker:


OEM KDX springs are not .42s. If that's what Racetech says..it's not the first time they've been wrong.

Most springs aren't marked. You have to test them to find out what they are. That's not too hard..involves making up a test 'jig' that will allow you to compress the spring (a dowel in it to keep it straight..or maybe put the spring in a piece of PVC..sepends on the rest of your setup) a given amount, say with it sitting on top of a good bathroom scale, do the math.

Or...take them to your buddy's place...the buddy with the spring rate machine.

OR...buy one'a these:



From HERE!

You wouldn't have to modify it TOO much to work on fork springs.