I just finished a build, its a cranny with a 62cc dax motor, my questin is that this motor as well as other motors that i see around town that are less than 67cc seem to make a lot of engine noise, sounds like the bearings rattling but run very well, my oil mix is amsoil somewhere between 32 and 40:1, the reason i say somewhere is due to i already had some gas mixed at 50:1 for my other mb so i added some oil to the tank and shook it, its not to much oil, any one know why these little engines make more noise??? I hope all that makes sense...
Engine Noise with 62cc
- Thread starter wes
- Start date
Next time ya have it runnin, at idle, clutch in standing next to bike, firmly press on clutch cover... Bet it cuts the noise way down, some folks put rubber "Dampners" in between the fins on the cyl. makes a huge difference. Pirate cycle makes a kit pre-cut.
As Mac was mentioning, a lot of that "sketchy bearing sound" is coming from the clutch. The gear case cover itself acts as a resonator and amplifies what's already an annoying sound. I quieted mine down quite a bit by coating the inside of just the cover with a few coats of rubberized undercoating 
As for why the lil ones seem to make more noise... I think that might just be a random luck of the draw more than anythin' else.
As for why the lil ones seem to make more noise... I think that might just be a random luck of the draw more than anythin' else.
part of the reason the larger engine rattles more is because the larger the capacity the greater the heat build up so the more piston to bore clearance needed. basicly the 66 cc engine usually has more clearance betweent he piston and bore than say a 50 cc engine . also you have a larger piston rattling around inside there .my 66 is the same .
the 50 made a grinding noise only when you pulled in the clutch because the retaining screw on the flower nut was touching the side cover only when i pulled the clutch in .i put 2 gaskets ont he side cover and the grinding noise went away
the 50 made a grinding noise only when you pulled in the clutch because the retaining screw on the flower nut was touching the side cover only when i pulled the clutch in .i put 2 gaskets ont he side cover and the grinding noise went away
My bigger 67cc engines have less engine noise, the 62 does have more clutch noise and more general engine noise, the oher smaller engines that i see around town seem to be more noisy as well.
