gearhead222,
I've been messing with motorized bikes for well over 10 years now and overall, I'd say the Chinese 2 strokes are much more problematic than the Whizzers.
Yes, some of the Whizzer's did come with a shoddy auto-clutch, but, the motors are well built and can be dead reliable with a minimum of tinkering.
I've built up several of the 2 stroke kits and can honestly say that they are hit or miss as far as quality. One motor (on the bike I built my father-in-law) is still going strong after all these years. Another motor I had self destructed after about 100 miles (wrist pin let loose and destroyed the piston/cylinder. Definitely not due to a poor installation.) I've known others who got a bad motor right out of the box.
Congratulations on getting one of the good ones.