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At a particular speed that may not be legal to disclose my bike wobbles from side to side. Anyone have any experience or could offer hints to cure it? Bike is bone stock no mods what so ever. Even have the ugly rear fender still on.
 

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sounds like an alignment issue.
 

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If your 190lbs + and haven't touched the suspension, perhaps this is adding to it at high speed?

Mine came pretty under spring from the dealer ( not that tightening made a big difference)
 

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+ 1 on alignment, then tire pressures. As an afterthought, are the forks evenly mounted in the clamps? (One isn't higher than the other.) Dealership setup isn't a 100% guarantee it's correct.
 

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Pay close attention to how much pressure you are putting on the bars. I know during some tracks once I got up over 100 I had to really pay attention and force myself to be light on the bars, the steering is very responsive as it is so if your holding on for dear life during hard accelerations you can induce a speed wobble. I had issues doing this coming out of turns and I would put uneven pressure on the bars while moving my butt back to center and the front end would get very shaky and wobbly the fix was to use my legs more and hands less.
 

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I'm 230. If I'm starting in 2nd gear and just take off to 100mph+ (on a closed course) with shifting, I usually get a wobble. If I'm in 6th gear already, and just pin it, I usually hit the limiter with barely any shaking.
 

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Front end is light. If you're hitting any little bumps in the road at 100+ while still accelerating you'll get some headshake.

Steering damper is a good idea if you're going to consistently run those speeds. I'm planning on getting one before the next track day. Speeds are averaging higher as I get more time on the track and I'm getting more headshake because of that.
 

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A while back I had intermittent issues with high speed weave, I think it was related to the soft suspension. After increasing preload and rebound damping all around, that issue dissapeared.

Then again I had a serious high speed weaving problem, a few weeks ago, which started after I installed a new front tire (does not sound like your case).

As part of the researching someone pointed me to this (old, yet still relevant)
, which explains quite a bit about high speed weave (start watching from about 4:10 into the video). The video points out 4 common causes for the high speed weave.

I found that sitting further back on the seat and leaning a bit more forward, helped reduce the problem drastically.
Ultimately my problem was tire related, and as soon as I changed my rear tire to a matching new tire my bike is totally steady, right up to the limiter.
 

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Suspension upgrades, dampner, and windshield totally smoothed my bike out. Before when I came out of corners hard in third, the bike would gyrate. . The long fork tubes don't help either.
 

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I'm thinking side to side is a weave. The first place to look for a high speed weave would be the neck bearing, and that it would be too tight. Lift the bike so the front wheel is slightly off the ground. Turn the bars their full range of motion. Pay attention for notchiness and binding. The notchiness would indicate bearings/races problems, hard wheelie landings can be the culprit for this. The bars binding would be too tight, and show itself in a high speed weave. The bars flopping from side to side is too loose, and would show itself in a low speed wobble.
 

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Pay close attention to how much pressure you are putting on the bars. I know during some tracks once I got up over 100 I had to really pay attention and force myself to be light on the bars, the steering is very responsive as it is so if your holding on for dear life during hard accelerations you can induce a speed wobble. I had issues doing this coming out of turns and I would put uneven pressure on the bars while moving my butt back to center and the front end would get very shaky and wobbly the fix was to use my legs more and hands less.

This.
 

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There is head shake and there is a low frequency oscillation at speed. I think you are asking about the weaving or hunting for a line feeling. I have experienced a slow oscillation at a high speed as well on different naked bikes. I have ideas to what it could be. One idea is, it could be caused by a "grooved" road surface. Such as a concrete freeway. Another idea is that most naked bikes seem to have the headlight and other assemblies mounted to the triple clamps which turn with the bars. I feel that the wind at high speeds influences the headlight assembly enough to move the front end around a little. I think body position (gripping the bike with your legs) and bike set up can help overcome it to a degree. But it seems that it is one thing that is common to the naked bikes I have ridden.

-Shannon
 
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