taco eater :
Derek Metal Ponies from Quincy, MA United States
Not all jets are created equally. Most PWK jet options, while very inexpensive, are total junk ("ball park" at best) which is unlike the carbs themselves (a great value). Jet orifices aren't on-center. Jet orifices are ovaled. I'm talking about brand new jets here. You're wasting your time/money if you're trying to build a tune around crappy fuel metering components. Now if tuning with crap components sounds counter intuitive...well that's because it is.
My bike ran no differently with a junk "105" and a different brand of junk "107". Popped a Polini 108 in - way rich. Polini 106 - still a little rich. Polini 104 - gravy. Fact is with these Polini jets, you can be confident that going up or down will do just that and in precise, intuitive graduations.
The accuracy and consistency you've been yearning 
