Rob666
New member
I have a 90 yamaha phazer II and it has an old PSI aftermarket exhaust on it. I know that you have to go to a larger main jet, but how much? It has the stock (143.8) main jets in it and im wondering if anyone knows how many steps up I need to go? Is a 145 enough? I just put a fresh top end in it and would hate to melt it! Any help appreciated
thanks
rob666
thanks
rob666
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