i am no expert on carburetors. when i buy an unfamiliar carb, i ask for the general recommendation based on the venturi, cylinder capacity, and anticipated rpm, and then buy at least three up and three down in jet sizes to have a range to test. there's no5oo way to know without testing. i had my race bike on a dyno one time, and the jets the operator recommended were three sizes too small for what i eventually set course records with. even now i may change jets several times a day based on engine behavior and RAD at the moment.right now i have 125’s, i just put in a wiseco 810 kit with the gpz750 cams. i have sizes down to about 110. not sure how the kit and cams will effect jetting . im looking to get 128’s thru 140’s just to cover everything. just in case. so thats 128, 130, 132, 135, 138, 140 times 4 times $$$$$. per jet. if someone knows that the ebc jets are crap, there you have it , ill go with keihin jets, i dont want to wreck a new race engine. but if the drillings on the ebc jets are correct maybe i cansave a little jingle. play on player
Real Keihin jets are getting harder to find. And even when you THINK you are buying Keihin brand jets, sometimes you find they are aftermarket jets...