I have seen the chain morty has and compared it to the standard chinese chain the quality is far better than chinese. Would definately be worth upgrading once you have the motor sorted.
Actually, an afterthought....has your mate fiddled with the motor? i fixed a motor for someone once who's kid had been plaing with it....he took the piston rings out...someone told him it would make it go faster...
The things people do..Yeah, the bin, mate.
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