Re: China kits
Well tuned carb, free flowing exhaust, doesnt have to be a high dollar pipe as long as it flows good, deburring the intake and exhaust ports is a good idea for better flow, port match the gaskets so they do not restrict flow and in my personal experience and opinion the stock rag joint/coupler works just fine, been running them on my bikes since 2009 with several thousand miles of fast riding on rough dirt roada and pavement and never had a single failure or issue of any kind, I have bikes that cruise from 30 - 40+ mph none of mine are stock and make good power with good cruise speeds.
Nice sprocket adapters are nice but when you run multi speed rear wheels like many do, the stock coupler is the most common and affordable option and does a great job.
It really doesnt take a lot of real fancy stuff to make a good running china girl, good tuning and just a couple better performing parts makes for a nice running bike that will give a cruise speed of 30+ mph easily.
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