Re: Where can a get a crank trued for a china girl??
You can true and balance a crank with some machinists vee blocks on pedestals, a shop press for the truing (they're often pressed together badly and bent from the factory), and a digital gram scale. There are some good online writeups for static balancing a two stroke rotating assembly, by putting the trued crank on the vee blocks and carefully weighing parts of it and using counter weights to test crank weight balance with the piston removed. After doing some math and geometry you will know where you need to take off some material to statically balance the whole reciprocating assembly, dynamic balancing is really involved and would cost 20x what you paid for the engine so I don't think its worth it, it's more useful for tuning out harmonics on high RPM racing engines.