Hi Had my 66cc for a couple of months now. Have since replaced the the standard pipe with SBP tuned pipe and the standard carburetor with an RT Dellorto knock off. I have also replaced the spark plug with NGK bh6s and the lead and boot. The bike has been getting progressively more difficult to peddle start and doesn't even fire with 'quick start' sprayed down the cylinder anymore. Last time I had it running, two days ago, I sprayed 'quick start' around the inlet manifold to look for vacuum leaks. I also sprayed on the joint of the crank case directly below the carburetor and engine revs went down with each spray. Waiting for the gear removal tool to be delivered so I can tear it down for a look. Has anyone else come across a leak in this location? And, would this issue prevent the engine from firing? I have good spark. Any feedback would be greatly appreciated.