Front end shake

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Front end shake

Postby marco220 » 10:25 am Jul 03 2006

Went out yesterday and on some high speed runs I had some noticeable shake in the front end. The ground was hardpack covered with some sand. The tire pressure was around 10lbs on a soft terrain tire (forgot to check before taking off). I pumped it up to 14lbs and it seemed to get a bit better but it was still there. The bearings have 3 or 4 rides on them, the rim is true and the clickers are about half way out. It's a little unnerving to get squirrely full throttle in 5th gear.

I don't necessarily want to go with a damper since 90% of my time is in the woods so the shake is not an issue. And I've got a list of mods to do before a KX setup.

Opinions? Cures?
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Postby IdahoCharley » 10:55 am Jul 03 2006

Headshake can be because of too weak of a spring in your fork for your weight. Likely a problem with the bike you ride if you are over 160 lbs when dressed for riding. Assuming your head (neck) bearings are adjusted correctly.

What may help is to ensure your forks tops are flush with your upper triple tree clamp - increases the trail and allows the bike to be more stable at speed. You can also increase the rider sag on the rear - this removes some of the weight that the forks now see and changes some of the handling charteristics of the bike. (could be good or bad for your riding style - just don't know)

For long term fix ensure your neck bearings are adjusted correctly and that you have the correct fork springs for your weight.

FWIW - Quick turning dirt bikes normally have a fairly steep fork angle and thus trade off some high speed stablility in the process. :neutral:
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Postby Colorado Mike » 01:36 pm Jul 03 2006

Mine used to get pretty spooky at the top end, like 65-74. The damper fixed that. I mainly got the damper because I mainly ride in the woods though. :lol:

I would do what Charlie told you, and you can also consider balancing the wheels. A buddy's xr650 is set up for desert, the wheels are balanced and it's pretty stable at speed. It also goes a lot faster, around 95 or so :blink: . That's danged fast on a dirt bike.
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Postby canyncarvr » 04:39 pm Jul 03 2006

FWIW...some anecdotal BS..

My bike has never had the shakes..and I've run it close to 80mph for quite a distance..dirt, gravel, asphalt. Solid.

My riding buddy's KDX DID have the shakes at high speed. Never did get rid of it.

Certainly check the stuff you know can make it happen.

NOT wanting a damper because mostly you're in the woods is counter-thinking. They work there, too!

Good luck. Let us know how you fixed it! :wink:

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Postby marco220 » 08:55 am Jul 04 2006

I guess I was a little confused on the steering damper... I searched around a little and now I have a better understanding of what they really do. Maybe that will be put on the mod list somewhere down the road if checking the other things doesn't help.

Thanks!
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