RE: CRRC 40cc kit
I ordered one of these out of curiosity since I enjoy building and tinkering with engines.
Out of the box, all parts seem to be of fair quality. Actually, better than expected for a Chinese product.
One problem from the start, however, the female side of the prop shaft that screws onto the crankshaft is tapped with fine threads and the crankshaft is course threaded.
If my guages are accurate the crankshaft pitch appears to be 1.25 and the prop shaft is a .8 or 1.0.
Apparently the prop shaft was tapped incorrectly at the factory.
I contacted the dealer I bought it from and he examined several kits in stock and found the same problem.
I am awaiting the solution as he is contacting the factory tomorrow.
Will keep you posted.