Low-speed wobble

[Atropine]

Hi all-
Just joined the VMax world. Picked up a 98 with 6200 miles last night. Overall, in very good condition. No 2nd gear slip, everything works, runs great, new tires, etc. paid $3400. No signs of ever being laid over. Owned by an older retired mechanic. Only one problem- on deceleration, if i just let it coast decelerate without applying any brake, at about 25 mph it starts to headshake pretty bad. As soon as I apply the front brake it recovers, but its pretty significant. If I decelerate while applying brake (either front or rear), it doesn't happen. I checked tire pressure (front 33, rear 36), fork air pressure (10), raised forks in clamps 1"; still no change. No free play in steering stem, but after reading on the forum about this issue, I still wonder if my problem is worn or loose steering stem bearings. I will check these asap, but I'm curious to hear from you guys if this sounds like the likely source of my headshake. Tires have only 300 miles on them and were supposedly balanced by shop. No wobble at speeds up to 70mph (as fast I test rode it). Wobble is ONLY on deceleration without the brake being applied.

 

[Traumahawk]

First of all check the steering head bearings.

http://www.youtube.com/watch?v=OW-CmACI5xQ

Thats the MOST likely cause.

 

[Atropine]

Great video. I'm ordering one of the steering bearing tools today. Thx!

 

[m-cman]

With only 6200 miles, I doubt you have any wear in any area of the bike. Just good adjustments should fix the problem.

 

[CrackerRican]

Mine would wobble only on the deceleration too, and at that time I had less than 10k miles on it. Had to adjust steering head , mention above, & it went away

 

[HyperPete]

I just removed an inexpensive windshield the previous owner had installed on mine and did away with the wobble on my bike...

 

[Miles Long]

Do all the checks and adjustments mentioned so far.
If you still have a low-speed wobble (mine was at 30-50 kph only), do the FURBUR FIX modification, but use a stainless steel washer, instead of an aluminum one.
I did this in 2008, after dealing with the wobble since purchasing the bike new (and checking and adjusting the steering head bearings several times).
Now , 68k kilometers after the fix, the bike is still wobble-free.
The "furbur fix" has been a controversial topic on this forum over the years.
All I can say is, it certainly worked for me, it may work for you, and even if not, you have nothing to lose. It's easy to do, and just as easy to go back to the stock (rubber washer) arrangement.
Cheers!

 

[SFCMcGan]

Great video...!

 

[Biker Dash]

Two very simple things to check. Tire pressure and preload in the forks.
Woona had been starting to act a bit squirrelly, and I checked the pressure in the tires and forks, and added as needed.

 

[naughtyG]

I would check the tire first! That's the most likely culprit. Badly cupped/worn front tires will do just that.

And then adjust the steering bearing according to the bounce test. Should be sorted then.

 

[[email protected]]

Mine would wobble only on the deceleration too, and at that time I had less than 10k miles on it. Had to adjust steering head , mention above, & it went away

+1
When my '06 had about 3K miles on it I developed a low speed wobble. If I took my hands off the bars while coasting it would get pretty bad. A quick adjustment to the steering bearings took care of it.

 

[Diablotin]

Bad tire, bad head or wheel bearings could be the reason. Simple check and replacement did the trick for me.

Sent from my GT-I9100 using Tapatalk 2

 

[sdt354]

Though I don't think this is our problem. Head bearings too tight can cause a low speed weave. I just thought that was worth mentioning. Most likely your tire is bad.

 

[Atropine]

Steering bearings were loose. Just tightened them up slightly like the video said, and problem is solved! Rides perfectly now with no wobble. Thanks everyone!