I installed a 80cc grubee on my road bike about a month ago. I couldn't get the sprocket from the kit to stay true on the hub, so I bought a 22 tooth sprocket from a bike store that threaded onto the hub. The bike flys when it runs like it should, but lately it seems to have no power. It will struggle to run one minute and then all of a sudden run great with lots of strenght. I'm baffled. I've never been able to get it past about half throttle without it flooding out, unless I have the clutch in. Several times it puttered out after running great and gas started pouring out of the carb. Do I need a better carb? Does it need adjusting? Why does it run great one minute and struggle so much the next?