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Old 10-07-2011, 04:09 PM   #1
Rich-in-GA OP
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Dangerous front wheel wobble at high speeds.

I was driving home today from a 5 day trip and experienced a near disastrous and uncontrollable front wheel wobble at 92 mph. I had been cruising along between 70-80 mph with no problems, but I accelerated to over 90 to pass a truck when my front wheel began wobbling uncontrollably. I backed off the throttle and eased on the brake, and the wobble went away at slower speed. I pulled off the next exit to check the tire and wheel.....Everything looked fine.

I run TKC80's on my GS.....Is the high speed wobble due to the tires or wheel balance, or is it something else?
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Old 10-07-2011, 04:15 PM   #2
whisperquiet
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Are your saddle bags fully loaded and a lot of the weight up high? The trunk on many bikes, your body, and the windshield cause some weird riding dynamics at times and can cause a higher speed wobble. Most bike manufacturers have warning stickers on the luggage/top trunk warning against speeds over 80 MPH....
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Old 10-07-2011, 04:18 PM   #3
mattjw916
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How was your bike loaded, suspension set, and tire pressures? I generally wouldn't recommend doing over 90 with knobbies and a big load on the bike like bags and crap strapped to it...

My RS used to get all sloppy with the panniers on as well over 90mph regardless of how it was loaded...
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Old 10-07-2011, 05:00 PM   #4
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I had 34 psi on the front tire and 36 on the rear. Bike was fully loaded Vario side and top cases......Maybe the additional weight in the rear combined with riding on knobbies caused the wobbling.
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Old 10-07-2011, 05:51 PM   #5
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What you want is this

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Old 10-07-2011, 06:03 PM   #6
erkmania
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I agree with the others that mention heavy weight in the rear and some of that up high. You might try preloading the rear spring some to transfer more weight/force onto the front tire. If you have the adjustment then you might also want to increase your rear shock's compression setting.

The most likely cause, in my mind, is that the rear tire has worn more appreciably than the front during your trip (guessing 1750 miles or so) and the geometry has been upset a bit. I feel confident that new tires would eliminate the sensation also.

Now, slow down and smell the truck exhaust.
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erkmania screwed with this post 10-07-2011 at 06:17 PM
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Old 10-07-2011, 06:25 PM   #7
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Check your rear wheel, FD and swingarm bearings.
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Old 10-07-2011, 06:29 PM   #8
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Did you adjust your suspension to compensate for the weight?
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Old 10-07-2011, 07:48 PM   #9
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Quote:
Originally Posted by Boon Booni View Post
Did you adjust your suspension to compensate for the weight?
The suspension is set as frim as possible.....But it's the original OEM factory shocks and the bike has 20,000 miles, with about 25% of those miles off road. The shocks are worn. I'm looking to replace them with new Ohlins but I just don't want to drop the bucks right now.
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Old 10-07-2011, 08:10 PM   #10
marty hill
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I've never used the tires your using but your pressures seem way low for a loaded bike.
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Old 10-07-2011, 08:18 PM   #11
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Quote:
Originally Posted by Rich-in-GA View Post
The suspension is set as frim as possible.....But it's the original OEM factory shocks and the bike has 20,000 miles, with about 25% of those miles off road. The shocks are worn. I'm looking to replace them with new Ohlins but I just don't want to drop the bucks right now.
If you mean the preload is maxed out, it's not the same as "as firm as possible" and maxing out on the damping is not right either. Furthermore, you may well find that max preload isn't max any more - or even close. See here for details but check rear end for movement and check bearings as suggested and I suspect you'll find your problem. Agree that your tire pressures seem a bit low for high-speed heavily laden running but that shouldn't cause a high speed wobble by itself.
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Old 10-08-2011, 07:29 AM   #12
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Too low of tire pressures and suboptimal weight distribution get my vote.
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Old 10-08-2011, 11:20 AM   #13
Stegerman
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Quote:
Originally Posted by Rich-in-GA View Post
I had 34 psi on the front tire and 36 on the rear. Bike was fully loaded Vario side and top cases......Maybe the additional weight in the rear combined with riding on knobbies caused the wobbling.
Ding ding ding ding....we have a winner.
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