Re: Top Speed, 80cc Chinese motor? what is the record?
There are additional methods available to reduce vibrations in a China Girl, which is one of the biggest limiters of RPM & speed, such as internal balancing. Most of us reading this do not have the equipment, knowledge base or skill set to do this ourselves. You might take your motor to a reputable machine shop with experience in 2 strokes or just purchase a prebalanced assembly from Dax, Arrow or CR Machine. Some have reported varying degrees of success by lightening the piston by drilling holes in it. But unless you have experience in rebuilding motors, I wouldn't recommend it, as it is far too easy to remove too much or cut the wrong location, resulting in a junk engine that will never run again. I tried using a lightweight titanium wrist pin & I can report that while it did ease vibrations, it didn't last, the titanium alloy used turned out to be too soft, it deformed within 10 miles & resulted in internal damage. At present, I'm awaiting FedEx to deliver me a new top end kit that I bought last week.
By the holy power of Love, Life & Laughter, I commend you to Go Forth & Be Awesome!