I bought my first motorized bicycle kit from boygofast right off the bat I knew something wasnt right with the engine, it knocked terribly loud, it would randomly make loud hissing sounds like it was leaking compression but it wasnt it had at least 185 psi of compression, and i could seriously pedal faster than the engine could push me. But if I let it sit for a min and cranked it but up it would take off like a bat out of **** then bog right back down to 15 mph. I was taking it easy though to break it in good but then it started knocking loud and made the loud hissing sound again and locked up! and my back tire started sliding. I pedalled as fast as I could and jumped and landed on the seat to put pressure on the back tire and popped the clutch at the same time and the back tire just slid. I emailed the guy I got it from and told him what happened, hopefully he will send me another one. What do you guys think about this? I know the casting is cheap and but are the internals of these engine really that crappy?