Hi dy2 theres not alot you can do with them mate,they are basically a clone of an old honda c50 cub engine with a starter motor bolted on there,i can tell you that they are made to run very weak to pass the eu emissions.so take the main jet out and either make it .10 bigger or buy a bigger jet so if it a 65 main jet then buy or make it into a 75 main jet.then you could get a 1 tooth bigger front sprocket for it this will give you more top end speed.Thats about it !i would personally put a 110cc pit bike engine in it if i had one and then it would be about the right power to weight ratio as these are a bike bike for such a small engine.you will find these chinese bikes to be a bit of a nightmare for spares and they often break down and parts break on them too.
adam bike doctor
May 2010
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