tharper127 Posted October 16, 2005 I have a CRF50 with a TB 88 kit with carb, cam, etc. The whole kit. (view Garage) Anyway, when i get to a certain RPM range, i hear this kinda like grinding / vibrating noise from the motor. It stops when i pass that certain RPM range. Is this anything to worry about? ITS DRIVING ME CRAZY!!! Share this post Link to post Share on other sites
five0addict Posted October 17, 2005 same thing happened to me i thought the clutch was loose or something and it turned out to be the swingarm pivot bolt. REALLY weird because that bolt made the whole bike jerk to the side. really weird lol Share this post Link to post Share on other sites
03sik50 Posted October 17, 2005 i dont think its necessarily anything major to worry about. Like stated above it could just be a loose bolt or something along those lines, something vibrating at that rpm. Share this post Link to post Share on other sites
Jetster220 Posted October 17, 2005 Yea, as long as the motor seems fine at other rpm ranges and runs smooth, its probably fine. Only thing that would come to mind that could cause such noises would be from the clutch, but youll know when it definetly goes as itll typically make a loud slamming noise and send a peice through the cases. Just go over and check all your bolts, as your probably just hearing something like that. Share this post Link to post Share on other sites
Zorac Posted October 17, 2005 skid plate?? the skid plate on my buddies bike makes a horrible noise at just the right rpm, sounds like the engine is running poorly, when its just the plate vibrating... Share this post Link to post Share on other sites
mxgilmore061 Posted October 17, 2005 Ya, last week when i was in like high rpms, the bike was vibrating bad and making noises, and it just kept getting worse so i checked the bolts. The huge bolt on the top of the motor holding it the frame was like ready to fall off. Share this post Link to post Share on other sites
tharper127 Posted October 20, 2005 Yep, solved my problem the other day. One of my skidplate bolts was missing and this terrible sound was coming from there. Thanks guys. Share this post Link to post Share on other sites
50 Hucker Posted October 27, 2005 try some blue thread lock, being on the motor its gunna have alot of vibration. Share this post Link to post Share on other sites
