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Hi everyone! I have a GPZ 900 cafe/street fighter project in which I have swapped in a 1986 GPZ 1000 engine. I've attached some pictures if you're interested!

Anyways, the engine isn't running properly. The exhaust is a custom with duel 2.25 ID glass pack mufflers. The carbs currently have K/N duel pods as show in the attached images.

Due to the modifications to the chassis and battery relocation the stock airbox will not fit. In the spring I may fabricate an aluminum intake manifold that can fit in that space which will flow air "similar" to the stock system.

So here's my 2 questions:

1) What size jets would you suggest for the new exhaust and stock airbox?

2) What size jets would you suggest for the new exhaust and the k/n pod filters?

Thanks in advance!

anyone?

You can't just throw out an accurate answer to questions like these, there are far too many variables. Start with two sizes up from stock and make sure to use a sync tool when making adjustments. You should also raise the jet needles a notch or two as well.