Motorized bike barely goes up hill

[Kajamaz]

Hey, so i'm having an issue, going across flat surface or down a hill is easy, the bike revs and you go lightning fast till the motor makes a rattle noise at max speed (i'm sure its because my chain tensioner isn't tight enough and the chain shakes and hits the bar holding the wheel although i'm not 100% sure). I have a question, what could make my motor not be strong enough to go up hill? Its new and its going through its break in, carb is open, gas is a flowing, and I adjusted the carbs idle speed (idk if its too low and because of that it causes it not to go up hill?). Its a 49cc motor. Please help! Thanks!

 

[crassius]

some older style motors take 60 to 80 miles to break in and get to full power - when going uphill if you can find a spot in the throttle where the motor starts to sound better and pull harder, then you're probably too rich and need to drop the needle a bit in the carb