A call to diagnostic gurus...

4 replies to this topic
  • KerryT

Posted May 06, 2002 - 01:04 PM


My '99 WR400 doesn't seem to want to go straight. While trying to go straight on a hard packed trail it has a tendency to want to turn a little to one side then flop back to the otherside. It doesn't favor one side, but like a gyroscope where you feel the inerta build up and then it wants to go left then you bring it back straight, the inerta builds up and them it wants to go right. Recent changes to the bike:

Small crashes but nothing major. I bent the front brake rotor where it was rubbing on the pad but I bent it back straight and that didn't fix it.

Lowered the fork tubes down a little to about 1 centimeter from the top.

Reduced the rear sag to about 3 3/4 inches, which is about an 1 1/4 inches less sag that it had.

Installed a Scotts damper but it had this problem before this mod.

Any ideas to what could be going on? Anyone else has this issue? Do I have bad balance?

I've crashed it about 100 times before and never had this issue!

Thanks in advance :)

  • Tony_Miller

Posted May 06, 2002 - 01:52 PM


Did you have the steering stem bearings apart? After I greased the steering stem bearings on my WR200 I noticed that the bike handled a little peculiar, kind of how you describe. It turned out that I needed a little more preload on the bearings. Don't know if this will help, but thought it was worth mentioning.

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  • moto_madman

Posted May 06, 2002 - 02:32 PM


I would check the head bearings. There was a thread about this in the YZ 426 forum.

  • MX_Tuner

Posted May 06, 2002 - 04:39 PM


What is your front tire pressure at?

  • KerryT

Posted May 07, 2002 - 07:07 AM


Well this is one of the neglected parts of my bike. I have a confession: I've never greased my headset bearings! To put the Scotts stabilizer on with bar risers you have to take off the headset nut. And after putting on the stabilizer last week it seems to be making a sqeeling sound from the headset when you turn the bars back and forth. Before I put the stabilizer on it did not make this sound.

The torque specs were off the chart on my torque wrench so I gave it some extra elbow grease when tightening the headset bolt. Do you think I over or under tightened the headset bolt and this could cause the problem I described?

I was running about 13lbs in the front tire.


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