really bad vibration
 

heres what i got a 1998 hawk w/ 40,000 easy mi. it was owned by a prof i work with. i have this vibration and grinding between 15-45mph worst at 33mph. it seems as if its coming from the frt spkt. the sprkts have 2500mi and i replaced the chain yeterday hoping thats what it was. i have balanced the wheels checked the wheel bearings repl the brakes and nothing works. im begeing to think its the countershaft bearings. i work at a bike shop and the mechanics r clueless. the vibration seems to be harmonic when u reach a certain speed its really bad. it dosent matter if the clutch is in or out either. its not constant but swooshes in and out and when im next to jersey barriers i can here grinding. its driving me nutz and i dont even want to ride the thing im fed up. please any info would be greatly appreciated. -ryan

Makes the noise @ the same speed no matter what gear your in?
Have you put the bike on a rear stand, wheel off the ground, have one guy run though gears and different speeds, and have the other guy try to isolate the noise?

Three bearings in the rear wheel, all three checked?

You can push the rear brake caliper in while it's on the bike to move the piston in and check if it floats on the shaft properly (single outboard piston.

While noise is there, front or rear brakes parcially on makes no difference?

That's all I can think of for now.
Let us know what you find.

~Jeffers

Re: really bad vibration
 

hey thanks for the reply but they did check out. im still not sure im getting a did chain.

sounds like the chain is too tight... simple, I know, but that's what came to mind.