1. The-DMV

    Loud gear sound when revving?

    When I rev my engine, I get hear a loud gear sound that's almost louder than the actual engine. Any ideas of what it could be? Here's a video I took with my phone: After riding for 15 minute, it seemed to get worse.
  2. Marine One

    Engine Trouble Knocking at Higher RPMs

    Hello all and great site yall have. Long time lurker, first time poster. I recently bought my first 66/80 cc motorized bike, it came with 1 spare engine and most of the parts for another kit. The bike had a large crack in the frame near the bottom where you pedal but I already had a better bike...