My happy time is vibrating like crazy and sounds horrible. The first thing I checked was to make sure it was mounted good to the frame. The mounts have came loose and caused excess vibration in the past. Well, it is solid. The bearings must have took a dump already. I have no idea how you guys are getting 6,000 miles out of these chinese junk motors. I didn't even ride mine that hard. I cruised at 20-22 mph with the 44T sprocket, and 23-24 with the 40T. I mixed my fuel 20:1. Oh well. Time to buy another disposable motor.