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Alright, I'll do that when I have the time
I have a Chinese 50cc scoot (139QMB). Basically, I put in a 70cc kit so I changed the cylinder and the piston + rings. After the swap, whenever I...
Lextek exhaust off Amazon, didn't expect much improvement but needed to replace the old rusted one and it was cheaper than other replacements....
Right I'll change the jet back tomorrow and see what happens, cheers
But would the main jet cause such bad performance at the lower speeds? And the valves were fine beforehand but now they do tick so I will have to...
Could the problems be caused by a too big valve gap?
How would I go about checking the valve clearances? And what part of the mixture would I have to adjust, and how?
At the weekend I took the engine off my qmb139 scoot and swapped the cylinder out for a bigger one (47mm) Put it all back together, put a 90 main...
Soon I'll be upgrading my scooter and I'd like help on what size jet to get. It's a QMB139 Chinese import, currently standard with a #78 main jet...
