Front Suspension Race Sag - Sticky Forx??

My front suspension doesnt sag much (30-40 mm) when I sit on the bike, back suspension sag is just right. Small hits seem to cause the front end to bounce off, but large hits are absorbed OK. Otherwise the bike seems to handle pretty well.

Any suggestions as to what may cause this ?

I bled the forks of air already but I havent had the courage to open up the suspension yet.

I believe the stock springs are still in the front and should be about right for me (95 kg with gear). Its a second hand bike and as the rear is OK I'm assuming the previous owner didnt mess with the front to cause a front rear imbalance.

The Missile


The Missile

'99 WR400F

Airbox Lid - gone

Throttle Stop - shorty!

Plastics/Tank/Seat - One Industries

Street Legal

when I had my forks re-valved by Pro Action, the technician told me the Yamaha seals are excessively sticky.

Maybe a track with solid whoops/rockers, and 13 hours of hammering them, would loosen up those sticky seals... :)

As a side benefit, you would end the day with Popeye sized forearms. :D


'99 WZ/YR (you choose!) with ALL YZ mods, de-octopused, DSP Doug Henry airbox w/ velocity stack, FMF PowerBomb header, Stroker SX-1 silencer, SS front brake line, OEM YZ tank, IMS YZ seat.

My philosophy is that the suspension have to work as much they can.

I set the compression of my suspensions by putting a nylon strap around the axle of the shock absorber and the forks, so that i can se the max. travel of the suspension. Soften it till u use the full travel.

You may harden it a bit for big jumps or whoops (or bumps in the acceleration area).

Nevertheless the Yamaha fork is a little stiff in the begin of the travel.

Good luck.

¤Yn@hg¤ do I stiffen/un?stiffen my suspension without changing the springs? On my mountain bike I have a preload winder that precompresses the spring to increase or decrease the force needed to start spring travel. Is there some mechanism on the WR to do this ? I understand about the compr/rebound clickers and they do not do this, they just change the speed at which the fork rebounds or compresses.

In any case I can uncrank the compression clicker to see if this softens up the front end on the smaller hits.


the missile

ynahg is right (i think). on the front you should look at some point for the forks to bottom out. to check this simply put a zip tie around your fork leg, go for a ride and go look. usually at some point in a lap your bike should be fully compressed-jump off the eiger and find out!

anyway, if you feel that your bike is generally behaving well but doesn't bottom out your springs will be too stiff. my 99WR came with .042 springs for a 75/80KG rider. i weigh 95KG and my .046 springs are perfect.

the internals on the Y2K were improved vastly and the springs brought up to .046.



Just a thought, but has the suspension fluid ever been changed? I had about 900 miles on my '00 when I had Mx-tech revalve/rebuild my suspension. They said my rear shock oil was totally trashed as the shock seems to get twice as much use (one spring/shock vs. two). I don't really jump much, either-mostly trail ride. They also said my front fork oil was also in pretty bad shape, not quite as bad as the rear but certainly would have caused excessive wear if I went too much further w/o having the oil changed.

All these particles could be clogging the valving enough to cause more sticktion than normal. Plus the wear I mentioned above. Yes, the '00's have lighter, less sticky internals but the '99's where pretty good, too and should perform nearly as well.

But I think your symptoms are pretty normal--the forks simply are harder to dial in and be pleased with than the shock. That's true on almost all bikes. Try reducing the rebound one click at time to reduce the bouncing feeling. Then reduce the compression to reduce jarring. Definitely use that zip-tie to determine how much travel you're using. Believe it or not, it's OK to bottom on the toughest obstacle. I'm right around 1" from bottoming when I ride, and about 1/2" when my faster friend rides it.

Hope that helps, don't forgot about the suspension fluid.

I thought my '00 suspension was pretty good, but wasn't pleased with the stiff action and the mid-range wall you hit. After the revalve, the bike felt lighter, turns waaay better, absorbed everything without tossing me offline (a steering damper helps, too), and was 10,000% more comfortable. The jarring action simply is gone. .46K springs at 195lbs + gear.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now