Sadly, the problems march on, and on.
Look for the following issues:
Blown head gasket
Loose head bolts
UN-believable head design [plug location, extra hole, small amount of small fins,bolt hole too near combustion chamber, etc]
Massive oil leaks
Excessive crankcase pressure
16 MM carburetor [jetted way wrong]
No right side lateral crankshaft support
Flywheel too small
Loose stator bolts
Wiring harness wrong at CDI plug [get a lot of calls about no fire]
Cylinder deck very rough [deep tool marks]
Head bolts stretch [grade 5]
ETC.
This is simply a ripped off Whizzer design with a bunch of quality issues.
Go ahead and buy them as they can be upgraded and made to work very well. Just don't hope to purchase the motor kit, Cruzzer kit, or whatever and expect it to be trouble free, because it is far from it.
If anyone needs information about fixing these motors, I will gladly supply it as I work on several of these motors every month. I will gladly offer DIY solutions to anyone who asks. I can also supply pictures of all the needed modifications & upgrades to make these motors stay together.
Just a quick fix for the defective wiring harness:
Pin 5 and pin 6 are reversed at the CDI. There are two sections to the plug, pins 5 & 6 are located in the small CDI plug with two connectors. Simply reverse the two pins in the plug, and motor should fire.
Have fun,