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post #1 of 15 (permalink) Old 08-26-2005, 05:58 AM Thread Starter
 
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high speed wobble

Looking for suggestions from any one that has experienced high speed wobble and what they have done to cure it.

I have a 2000 zx9r and I notice that once I exceed 140ish, especially in slight corners, I start getting some wobble... almost like a very mild tank slap. Any suggestions on what I can do to cure it? The only thing I can think of is front suspension settings?

Anyone?
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post #2 of 15 (permalink) Old 08-26-2005, 06:06 AM
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Suspension, tire wear/balance, road surface, etc. Any number of things can contribute. Make sure your tires are in good condition and balanced, then perhaps check the suspension. Maybe take it back to the stock setup if you've changed it, and start fresh again. A steering damper would also help, but it's more of a bandaid on a bullet hole in cases like this, IMO. I'd rather find what's causing the problem and fix it rather than just try to minimize it.

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post #3 of 15 (permalink) Old 08-26-2005, 06:09 AM Thread Starter
 
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thanks for your input... I guess I should have been more descriptive in my post.

new tires 4K ago... front is flawless rear is showing signs of wear. The road surface was perfect, flat not cracks or imperfections... just paved last year and is still great. The tires should be in balance but I could check it again. I know they were balanced when I had the tires done. For some reason I am thinking it has to do with one fork being set or responding different than the other... would that do it?
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post #4 of 15 (permalink) Old 08-26-2005, 08:38 AM
 
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Tire balance is the easiest thing to rule out so do that first. The next thing to check is alighment of the rear axle. If you gotten it crooked while adjusting the chain the result could be the same.
Aeordynamics could be another culprit, but its hard to figure out. Do you have any broken fairings/tail section? It would have to be a pretty big crack. Or perhaps you had some cross winds? Run the same road in reverse direction immidiatly and see if the shake repeats itself.
Could one of the brake rotors be mildly warped? If so it would compress one of the forks more than the other.
4k miles on the tires is also enough for them to wear considerably.
Finally depending on how old your bike is, forks could be wearing unevenly. Diagnosing those gets expansive, start by changing fluid, and making sure that the settings are the same on both sides.



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post #5 of 15 (permalink) Old 08-26-2005, 09:31 AM
 
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I would definitely check tires, suspension and front forks in that order. My guess is a little uneven tire wear, like Vash said, 4k is plenty to see some wear.
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post #6 of 15 (permalink) Old 08-29-2005, 05:06 AM Thread Starter
 
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thanks guys I will look into this....

I am betting on either the rear tire is not aligned well enough or the forks. The tires look mint! The front appears new... and the rear is worn evenly not a flat spot on the top or anything.
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post #7 of 15 (permalink) Old 08-29-2005, 07:29 PM
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Tires. I seldom see much over 4k (except on the Dunlop D207). I had a bike just start doing all sorts of weird stuff and it turned out to be my tires.

Aside from that, ensure your suspension is set right, and that your fork oil has been changed within the last 15K or 3 yrs.

Dan
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post #8 of 15 (permalink) Old 08-31-2005, 07:27 PM
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DanQ u must mean rear tires, i can definetley say i never survied 4k on my rear tired even at times when i ride super conservative, but front tires, i mean i can vouch for seeing a front tire last 8k without showing any wear at all, and thats when i first started riding and was riding my bike very hard and in the florida heat

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post #9 of 15 (permalink) Old 08-31-2005, 10:58 PM
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First thing I would look at is the steering head upper and lower bearings. Not that they are worn on a bike that new, but those spanner rings that hold the bearings in place can loosen, I have had it happen on fairly new bikes. Simple problem with a simple solution. WARNING: do not over tighten the bearing rings!

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post #10 of 15 (permalink) Old 09-01-2005, 05:43 AM Thread Starter
 
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thanks for the info fuster... that's a good idea... I do a great deal of wheelies and I am sure that can contribute to them wearing.
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