Just picked up a 1995 cbr 900rr about 2 weeks back. Im having this sound (sounds like a marble hitting a wall), coming from my carburetors. Im wondering what I could do to stop the noise. A friend tells me its something lose like the valve. Another friend is telling me the timing might be off. All I know is when its idleing you can still here it. When I ride, it rattles more. It feels fine but the sound is so irritating. Can anyone figure out what this noise is?? Also forgot to mention my bike has aftermarket carburetors, and no air box.

 

It sounds like you have a rattling & loose Cam chain, the tensioner needs to be replaced.

 

If this is the problem is it possible for me to replace it myself? Or do I have to go to the mechanics? And where would I find a part like this online, any suggestions?

 

Its a common problem, do a search for it here on the forum, I have not done it myself, but its supposed to be pretty straight forward & you can do it yourself.

 

You should have post this in the 900 section; alot of experts in there. Maybe the mods can help to move it.

Sounds like cam chain tensioner to me. Unless you are mechanically inclined, I suggest you get her to the shop. A good thing will be to check with the previous owner too.