Bottoming front forks

My 01' 426 has five rides on it and I'm up to speed with this four stroke riding style and now I'm bottoming my forks 1 or 2 times a lap. I stiffened compression 4 clicks and its better but before I go with a stiffer rate spring I wanted some opinions. My last bike became a little harsh with the stiffer rate. How about 10 mm more oil. I'm 180 lbs. and ride 250 intermediate.

I'm at 100mm oil height, stock is 130mm I think. Raise the level so you can keep the clickers out. I am at 6-8 out.

I ride 40 Exp 200lbs.

I recently had my suspension done by MX-Tech (AWESOME) and they did not advise changing the fork springs for me (225, mid-pack "C"). The WR's use a .46, not sure what the YZ spring is though.

I would think an fluid level adjustment is what you need.

Also consider, that it's not bad to bottom on the same monster jump to keep the bike plush for the smaller obsticles on the track.



99 WR400f, YZ timed, MX-Tech suspension, Scotts steering damper, White Bros E-Series (12 discs), tapered header and a/f. Kouba T-handle for the fuel screw. Works Connection billet throttle tube and frame guards. Cycra Pro-Bend, triple clamp mount handguards. Thumper Racing rad guards, Renthal Jimmy Button highs, YZ Tank and IMS seat, YZ number plate, odo removed, EKP, 48PJ, 175MJ at 500-1000' Thanks James Dean!

I raised mine to 100 also and mine are actually a little stiff now, next oil change I'm going to 110. I am about 205 lb's with all my gear on...

One thing to remember when raising the oil height. The fork seals are suspect with these bikes. If you raise the oil height too far, it could cause enough pressure build-up inside of the fork to cause the seal to start leaking. Put oil in at 5mm per addition until desired results occur. I had to add 10mm of oil in mine to get where I like it.

Bill is correct when he says that an occasional bottom is ok. You just do not want it to do it more than maybe once or twice a lap. Personally, I would never go higher than 110mm from the top.


Range on the '00 is 80-150 mm. I have mine at 100 and I'm still on the original seals, no leaks yet... Mostly MX (about 25 races and about 15 practice nights).

I was bottoming my 00 forks a lot, raised the oil to 95-100 and they are much better now. That is the easy and inexpensive fix.

OR, a complete revalve if you want to spend more money and hopefully get a better ride.

Dave s

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