I have an animal engine that is basically new (about 15 minutes of run time after initial warm up). I noticed a strong vibration at about 5400 rpm, above that it is very smooth. The chain was disconnected to isolate the problem and it is the engine. It is so bad that the handlebars are uncomfortable to hold (engine is on a minibike). Is vibration a normal thing with these engines? Thanks
Yalipito
Yalipito