What size jet?

[geo0101]

Hey, I'm new to this 300ex. I just purchased a HMF slip on muffler and K&N filter, what size jet for the carb do I want?
thx
geo

[JParisi48]

i just put a 128 main in mine an it worked good, same setup as you

[bwamos]

With the stock header, I'd agree 128-130 should be a decent starting point with a vented airbox lid.

[geo0101]

Thanks guys I appreciate your help
geo