i did almost everything to my 660,then it gave me a slight increament of the power only.
like munpeng at the first, change spark plug,plug cable,3 in 1 downpipe, bigger muffler.
port polish, head skimming, fly whell lightening,open air filter,CAI.
had spent thousand riggit on it.
also think of sticking back of my ori engine.
but last change to L2s.
if i know the power only gain so little, then i will spend my money just to stranfer the engine better:emoticon_U:
advise to munpeng, want power change engine.that's it.
u will satisfied