Well i have a rumbling sound when i hit around 3000 rmps. Sounds like something is loose and vibrating. Kind of annoying. Anyone else have this problem? Or any suggestion on where to look? Thanks guys/gals

 

I wouldn't call it a rumbling, but on mine the screws that hold the metal braces on the back rack tend to loosen off and cause a vibration noise at certain amplitudes.

 

check the rubber pad the head pipe is resting on. The heat and vibration where out the rubber and it rattles. the retainer springs will get loose when the pad wears. It happened to me 2 times

 

mine vibrates, I noticed a piece of rubber fall off one the header mounts recently.

 

RP700........
I've also had to change the rubber stopper which supports the exhaust by the head......After awhile the heat deteriorates the rubber and you end up with metal on metal.......Easy fix...........Poor design....
The other noise I have is on the top of the battery there's a small metal bar which holds the battery which I've noticed to be rattling recently.........Just a couple ideas.....

John