Random clunk while riding.

I have a 2007 with approx. 2200 miles on it. I have been getting these random clunks that I can feel in the footpegs from time to time. They coincide with driving over pavement cracks. The best way to descibe it is it feels like the tire is flat and the rim is hitting. Kind of like when you were a kid and your bike tire was really soft. Not flat but soft. I can't reproduce it consistently and it feels like it is within the frame or engine more than the tires.

The tires have plenty of pressure.

I can't feel it in the triple tree.

No signs of chain slap.

Brakes??

Feels like good size rock hitting the bottom of the bike. None around though. Clean pavement.

I checked the centerstand and it is pretty secure with the springs.

Any ideas??

 

Might want to have a look at the rear suspension linkage, but with only 2200 miles it's hard to imagine there'd be a problem there.

 

Is your tool kit, or anything else, flopping around under the seat?

 

Odd you posted this, my 1992 is doing the same thing, can't find a reason for the clunk either. Nothing loose under the seat, not chain slap against the swingarm, can't hear it but just feel it through the footpegs. It feels like the same 'clunk I used to get when my dirt bike forks would top out over sharp jumps.

 

My '97 does the same thing. I think it's the centerstand moving down just a bit when the bike hits the crack/bump and what we're feeing is when the cenerstand comes back up against the stop. Well, that's what I'm goin' with because I can't find ANYTHING else it could be.

 

I have something like this once in a while when hitting a good bump, but I am pretty sure it is the front suspension bottoming out....is yours all the way out maybe?

 

My guess is too much high speed compression damping inherent with the stock shock.

When the rear tire hits a sharp edged bump, the stock compression damping can't keep up with the instantaneous internal fluid pressure and it hydraulically locks the shock, hence the sharp hit or clunk you describe.

It could be the centerstand, but i'd bet against it.

 

|I agree with the other guys but one other thing to look at is to see if your chain may have been defective and thrown a bearing link. This would not coencide with bumps but revolutions of the wheel. My last bike (gsxr) did this... not noticable for the first 4 or 5 miles but when it got warm clunk... clunk... clunk... judging buy the syyptoms maybe not, but it cant hurt to check the chain over well. put it up on the stand roll the wheel, see if the chain changes tension and inspect the inner race of the chain after you make sure the center stand is secure.

 

I recently got to see what you describe up close. The original post indicated the clunk couldn't be reproduced consistantly. The description in the post about the clunk occurring when encountering pavement joints at speed, is a pretty good indicator that it is a rear suspension related issue....just my .02.....now, .04, but wtf do i know.

 

Mine does the same thing. It almost feels like the rear shock is hitting the top of
its travel.

 

I have peg lowering blocks on my 07 and the side stand used to rest against the bottom of the block (metal to metal) and I could feel it knocking over transient bumps.
I ended up wrapping some thin rubber around the side stand so it wasn't as noticeable.
Both of the stands do jump around a bit; In order to troubleshoot my clunking, I zip-tied the center and side stands so they could not move and took a ride; this completely eliminated any clunking.

Now that I know the characteristics of the stands, the clunking does not bother me; it really doesn't do it that often where I ride, and is really pretty subtle when it does happen.

I'm not sure if this is your problem too, but you could give the zip-ties a shot and at least eliminate the stands as a cause.

Matt

 

Are you sure it's not your teeth?? :biggrin: