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Discussion Starter #1
I have 6500 miles on my 2001 R6. I ride almost everyday, and since I commute on a 2 lane road, I reach 100+ almost daily when I inevitably have to pass someone.

Friday, I was riding with a buddy on a rough, paved, highway. (Hwy 101 in WA) The road was straight with a slight downgrade. I wound it up to about 105 and was still accelerating when the handlebars began slapping back and forth violently. Happened for about 1 1/2 seconds. I immediately got off the throttle when it happened and it quit.

I've heard the expression, "high speed wobble"
My questions are:

1. Is that was I experienced?
2. What causes it?
3. Should I worry about it happening more?
4. Steering damper is the cure?

I've got years riding experience, but never experienced this on any of my cruisers. This being my first sportbike, I'm learning new stuff almost daily. This one was a little more exciting than I liked for that brief moment. I just want to know how serious a problem this is and what to do to fix it.

Thanks in advance
 

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That wobble is from the front tire picking up and getting barely any traction, yes you need a steering dampner and also adjust your suspension, so that there's more weight on the front end. Some people also lower there triple tree's a little.
 

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As for getting off the throttle Im not sure about that. I had something similar happen yesterday. I was riding a wheelie in second and tried to shift to third but wasnt quick enough. The front end came back down and touched about the same time I got it into gear. I stayed on it and hoverd about a 1/8 inch over the ground, I started to tank slap bad I left off and it was still doing it. I remembered something I saw here for some reason " when in doubt throttle out", and I reved up and dropped the clutch.The front end came up and back down with no shaking this time.
Shannon
 

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Dude, I have had the "speed wobbles" on two occassions in my short existance here on this wonderful planet....all I can tell you is that once I was going downhill on a skateboard and the other, I was straightline at around 80 mph on an enduro (Yamaha XT225). Basically if you through anything going in a straight line off balance and I mean unnatural balance, such as: trying to sit on the gas tank and screwing up.... the ends are going to want to swap.....best solution when it happens, let off the gas!!!!! Or if you're skating bail! It sux though! I've also heard that your wheels being out of balance or forks bent, can cause it too.......:D
 

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were you accelerating hard when this happened or a steady, gradual acceleration?

what you probably experienced is the "speed wobble" that shannon muse mentioned.
this occurs a lot more with the nimble powerful bikes of today, you pretty much have to get used to it. especially if youre going to accelerate hard. a steering damper will help, but you really shouldnt need one with the R6, with the bigger bikes, it is a must.

you should adjust your suspension on that bike if you havent done so already,
http://www.2wf.com/articles/how_to/673D0947-3FD0-417D-9671-8AD39F35A8E9.asp
...gives a great how to using the R1 as an example, but this is a universal process. all bikes should have this done after buying.
you'll notice a huge difference...
 

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Discussion Starter #7
I wasn't HARD on the throttle. I was accelerating gradually from 60 mph up to 105 mph when it happened.

(Accellerating gradually being defined as, kicking it down to 5th gear and opening it up to about 80% throttle.)

I've been scouring the internet for info on this...and learned basically what you said here.

1. check my tire pressure.
2. Adjust my suspension, ensuring that at minimum, the sag is set appropriately.
 

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The problem, Spiderman, was that you were on the wrong side of Puget Sound.:D

Look, there are already ten sportbikers over here - that's plenty. Stay on your own side. :D
 

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Discussion Starter #10
I was just passing through....

I live on the "right" side of the sound. ;) :p
 

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I am going to brief everything others have said:

You need to check the following
  • Your suspension (preload)
  • Your manual should suggest that you are to have the steering head bearings tightened on your first service
  • tire pressure
  • go ahead and get a steering stabilizer. It will help.
I have an R6, so I know what your experiencing. I had the same things happen to me. I found that the stabilizer and suspension adjustment fixed it just fine. When you have a light weight machine mixed with high speeds your going to experience some laws of physics.

As far as the preload adjustment, it sounds like it is too stiff.
 

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VYPIR said:

... your going to experience some laws of physics....
Don't anybody DARE!!!:D
 

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All that has been said has merit, especially on lighter bikes, and may be the cause, but another thing not mentioned is to pay attention to how you're anchoring yourself on the bike. If you're holding on by the bars, that will also aggravate headshake. When you hit a bump, shift your weight, etc. you can make an unintended steering input which can start a shake and then tightening up to try to "muscle" it out can make it worse. Just a thought.:)
 

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Spiderman said:

(Accellerating gradually being defined as, kicking it down to 5th gear and opening it up to about 80% throttle.)

I woudl say you got your font wheel off the ground a bit... except for the fact that according to your description, you were in 6th at 60MPH.. not a whole lot of kick there.. and then downing to 5th, still would not punch it all that much.
 

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A steering damper is a good thing to get but with your particular bike that shouldn't happen the way you described it. Don't go and lower your front end. There's no reason for you to do that. It won't transfer that much weight to the front. Sliding the front end down the fork tubes a little bit causes the front fork to sit at a steeper angle which makes the bike much more responsive. The side effect to this isless stability

You need to go to a shop and have them balance your front wheel. Always keep an eye on your tire pressure for you own safety. Its obvious that your front wheel is very unbalanced which will cause what you experienced.

P.S.
If you don't know what your talking about, keep it shut. Telling him to lower his front end, thats just plain stupid. Does he sound like he's trying to make his bike more stable or less stable? Come on man! Don't give advice if you don't know what your talking about.
 

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gipson said:
[BP.S.
If you don't know what your talking about, keep it shut. Telling him to lower his front end, thats just plain stupid. Does he sound like he's trying to make his bike more stable or less stable? Come on man! Don't give advice if you don't know what your talking about. [/B]
Hi New member I'll start off by saying blow me:finger:
Everyone I know has the triple trees lowerd to put more weight on the front end, they asked me when I bought the damn thing if I wanted it done (they would do it free). Thats at the kawi dealership by the way. Your can post YOUR opinion without the smartass attitude.
Shannon
 

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I agree with Shannon. Nobody wants to see you verbally slam people because you think that they were incorrect on a technical issue. There are much more intelligent ways to "correct" someone. By the way: You can not say that "It's obvious that your front wheel is very unbalanced...". There are many variables that can cause head shakes at high speeds. If this rider's tire was unbalanced, then there would be a gradual increase in vibration as a function of speed, not a sudden violent head shake.
 

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spiderman,
make sure and check all your bearings as well
steering head bearings, front wheel bearings,

ive had bad bearing buck me right of an F2 before, on the track, without notice, coming out of full lean...
 

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I had a similar problem on one of my bikes. My front tire had a tread groove right down the center of it and on certain pavement, it would cause it to wobble. I switched to a different tire and the problem went away...

Just food for thought...
 
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