Hey All, I just bought my first bike (91 F2 w/ 13k miles) about 3 weeks ago, I notice there is an engine vibration around 4k-5k rpms that I can feel in the handle bars, it's not really there any lower or any higher, the bike runs great and is not noise when it first starts or idles, just has that vibration, was wondering if that was just normal engine harmonics on these bikes or is there something I should check? thanks.

 

I remember when I first got mine and I noticed it alot. Now I don't really even notice it at all. I think there are some other posts on here about it but I think the consensus is the same, its just the engines frequency matching the resonance of the bike. Kind of a weird effect but thats my best guess.

 

My bike had brutal rumble and vibration through the whole bike.

What caused it? The gas tank.

Our gas tanks are bolted on the top and bottom, and those bolts are perfectly aligned. The tank can rock back and forth freely as the sides sit on the frame.

I fixed the vibration by adding a line of sticky sided foam strip along both sides of the frame where the tank rests. As well, the bottom of the tank vibrates against the back of the air box,I added some foam strips there as well (You may see where it is touching due to rub marks on the tank and the box)

After I did that, no more vibrations, and no more numb-fingers.

Hope this solves your problem, check it out and see if there are rub marks on your frame and airbox, or simply try squeezing the tank with your knee's when you feel the vibration start, if that dulls the vibration you have narrowed it down some!

 

thats interesting, my bike has two large portions of thin foam on the underside of the tank that appear to be from the factory. I would have just assumed something like that would be there, but maybe not if the bike has been repainted or something.

 

I fixed the vibration by adding a line of sticky sided foam strip along both sides of the frame where the tank rests. As well, the bottom of the tank vibrates against the back of the air box,I added some foam strips there as well (You may see where it is touching due to rub marks on the tank and the box)

^^^^^^^^^^ my airbox actually rubbed a handfull of pinholes on the bottom of my tank so I put those foam strips across the top and sides so it wouldnt rub anymore. Now that I think about it I dont notice much vibrvation anymore either[sm=smiley20.gif]

 

Glad I could help! It's a pretty goofy setup how they have the tank mounted, but I guess there's really no other way... The foam does the trick perfectly though

 

I don't have any "rumble" issues, but the engine's resonance does effect my right hand on a ride for any length of time...[:@]
RB

 

I have heard that heavier bar ends can solve vibration through the handlebars, maybe look into that?

 

Sounds interesting....Thanks!
RB

 

I did the foam on the airbox and tank/frame. Deffinitly helped, the rumble that was there is gone, I still get some vibration in the handlebars which I think is just the engine harmonics. Anyone ever try the heavier bar ends? wondering how well that works....thanks for the help.