Handle bars oscillate(left to right) at high speeds, kind of scary

[amdderik]

This generally only happens on rougher roads but sometimes it happens on smooth roads too. The handle bars start to oscillate from left to right when I am going faster than 65MPH. The other day I was on a fairly rough country road, going 80MPH and to keep the handle bars from going crazy I had to keep constant pressure on the grips, basically pushing the grips equally with both arms so that they wouldn't get out of hand.

Do you guys have any ideas as to what the problem could be?

Thanks,

Derik

[Jon-D]

It sounds like your rear tire has low pressure (or low for the speed you are riding at). Same situation happened to me on my road bike when I hit 80 + mph. The bars would swing violently back and forth and from my prospective I thought it had something to do with the front end. A buddy of mine who was ridding beside me at the time said the bike's rear end was bouncing back and forth, not the front. Although I thought I had enough air pressure, after adding some more (up to the limit of the tire) it cured the problem. Give it a try and let us know if it worked for you.

[motomonte]

Maybe you should check your geometry (the bike that is)if you lowered or raised your bike that could be the problem,also installing new tires may cause that problem.In fact I have that very same problem right now,and it started after installing new rubber.IT IS SCARY.I just have to seat as back as possible to lessen the effect.( maybe the new rubber sits lower than the previous one even when the tire ratio is supossedly the same as the ones replaced?) Just my two cts. be sure theres some guys here that know much more,be patient,they know.....

[pigryder]

Dude have you set your race sag? How bout tightening your headset?

[slomotobug]

Buy a scotts setup, you can do 110 and not even touch the bars! before that though, try moving your fork tubes down in the triple clamps and tightening your headset, and like they all said check your tires and rear sag.

[amdderik]

Sweet thanks for all of the good info.

A couple of weeks ago I did tweak the handle bars when I crashed off-roading, could that be affecting this situation?

The only problem is that it did this before; however, it might be doing it worst now.

Thanks,

Derik

[slomotobug]

Sweet thanks for all of the good info.

A couple of weeks ago I did tweak the handle bars when I crashed off-roading, could that be affecting this situation?

The only problem is that it did this before; however, it might be doing it worst now.

Thanks,

Derik

loosen everything up in the front end after a crash, t-clamps, headset, front axle, bar mounts, and make sure everything gets realigned, after a crash, the forks, bars, and axle can twist in the clamps and cause funny handling and feel like bent bars, try to realign everything in the front first, and try running the forks lower in the clamps with the headset a little tighter.

[Chas_M]

Check sag, steering head bearings, tire air pressure and wheel bearings. Also, especially at those speeds, tires must be balanced.

[chicagobikefan]

My '05 XR650L has a completely stock front end and is pretty stable at 80. The advice already given sounds good.

[XR_mad]

i was doing 68mph in 5th up a hill didnt feel the front end shaking because it wasnt on the ground ?, ive never ridden a bike that could do that before ?

[GUMBYXR400]

Here is a good site for tuning your suspension:

http://www.off-road.com/dirtbike/tootechp1.html

Read the very last paragraph for head shake.

Also at speed if you push your elbows out more, like your gonna hug someone it will help at higher speeds.

[captb]

You can check the rear wheel alignment sometimes the marks are off on the chain adjusters, some use a string, I used a lazer line mounted on a block on the rim (rear) to shoot a line on the floor one side at a time and checked the distance on the right and left of the front wheel (should be the same) my CBRXX was bang on but the XR was 1 inch off left, I adj both adjusters exactly the same amount now after compensating so I don't have to recheck it. It track good now I am at freeway speeds (75 to 80) alot and no problems.

[motomonte]

Hope you find your problem and fix it.It would be helpfull if you let us know if you fixed it and what you did,thanks ?

[gnarly sprockets]

Holding on too tight can increase the wobble.