I have 2 50cc scooters and live in the mountains in VA. One is a 2008 ATM50-A the other in a 2012 CY50-A. Both Chinese bikes with the GY6 motor.
Most hills don't give either bike a problem. The ATM50-A will start slowing down going up steep hills hits about 10MPH then the motor sounds like the RPMS raise up and then pick up to 15MPH till I get to the top of the hill. On flat land the bike will do about 43MPH. The CY50-A will handle most of the hills at about 20MPH but there are a couple of hills when start climbing them I have to get off and walk the bike up them. The motor never makes the sound of the RPMS rising, RPMS just drop and bike quits moving. Never had this problem with the ATM50-A.
Both bikes
Spark Plug Autolite 4194
93 Octane Fuel with 1oz to a gallon of Turbo 108
Stock Carb
Stock Coil
Stock CDI
ATM50-A
New CVT Belt. Even with the stock belt I didn't have any problems.
Thank you all for any help.