Strange Noise and Vibrations...


New Member
Apr 29, 2019
So I've been riding my 80cc 2 stroke bike for a good 6 months now with minimal problems. But the other day on the way home from work it began to vibrate like heck. The muffler quickly loosened and fell off. Also the sound the motor is making has changed. When going 20mph is sounds as if it is going 40. It is almost like the rpm, is way too high for the speed it is going. But it is perfectly normal idling, and going up hill. Any thoughts on the problem? I am using a 6.4 oz to 1 gallon of gas fuel ratio. I also bought 91 unleaded gas, and a higher quality oil to what I was using, but to no avail. Thanks!

EDIT: Solution - Torque the heck out of every bolt on the engine.
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Well-Known Member
May 1, 2011
Newnan,Georgia U.S.A.
Welcome to the forum, you are right things get loose quick on a motorized bike. I don't know if you have a rear muffler hanger but it helps a lot. I do a check before every ride just to look at all the trouble spots, muffler, carb, engine mounts etc.