KDXRIDER.NET

I just got done rebuilding a set of 2005 kx250 forks. I did the fork swap and read every post I could find on getting the valving right. I removed the bladders and took about half the shims out of the base valve. I didn't mess with the mid valve since I couldn't find any recipe anywhere.

Everything went together fine. I am running 135mm of 5wt oil. both screws are fully soft. I also checked to make sure there is no side pressure on the legs when tightening the wheel.

I don't have any experience with mx forks but am blown away at how little movement I can get from them at a stand still. Even when I roll the bike and hit the brake it barely moves. Sometimes it will even slide the wheel instead of compressing.

Is this normal?
Are the 250 springs that much stiffer than 125?
can someone offer a recipe to dramatically soften these things up?

springs on the 250 are much stiffer than the 125.
make sure you have the front end bolted in the correct sequence, it could be binding somewhere, could be a reason why they are stiff.
There is a post somewhere here on the proper method.

try loosening the lower triple clamps - see if it frees up - if not someone may have put stiffer springs than stock in the forks.... IMO the stock 250 springs should move just fine static - I'm running stock 250 springs in my kdx 220 and they work good for me at 165 lbs.
The triple clamps have a light torque value - 14.5 to 15 ft lbs... barely tightened, comparitively speaking.

a typical 250 runs .43 springs, the 125's run .41 kg/mm..... using 2001 as an example.

Also, loosen the axle pinch clamps to see if that area is binding the forks...always work the forks up and down with the brake on to position the forks on the axle before tightening the axle pinch bolts.

You should feel my 450f forks

casola - I had the same thing with my 450F forks. You need to install the wheel properly to prevent the forks from binding. Check an OEM manual - I downloaded one via google.

Wibbs - try revalving it unless you like taking a beating. Check out my TT thread.

http://www.thumperpud.com/forum/showthread.php?t=991787

http://kdxrider.net/forums/viewtopic.php?t=1107

or check that thread

thanks for the replies. I'll try retightening the forks in this sequence. I pretty much did it the same except for the spinning of the wheel stuff.

Anyone have any .41 springs?

On a side note. I just did an exploratory ride to aetna mountain in chattanooga today. 5 miles from my house. My word! freakin unbelievable.

When I did mine they were way to stiff at first. Much like the binding you are talking about. I tried all the different tightening steps with little help. I gave up and just rode it, after about a ride they were moving well and acting better. After you try the tightening steps if it still feels sticky try riding it some and see if that helps.

I replaced just the fork seals on a KTM and thought I had goobered up something badly.
1/2 hour ride and all was well. They did not leak any more, either.

don't waste your time revalving, etc until you put in the right weight springs.

I just put 0.42 main springs and 1.0 ISC springs into my 06 KX450 forks, and wow! what a difference. They now move when I sit on the bike to measure static sag.

(no, really, they didn't move at all before the springs, even with a revalve)

my .47's move when I get on

it might have been the extra 75 cc's of oil my syringe put in. 350 ml instead of 275 ml.