My sons 98 cbr600f3 has a lean condition. It has no power in 5th & 6th gear & wont go over 6k in those gears. It has a 2 brothers exhaust & k&n air filter. My question is what kind of carbs do they have, what is the standard jet size & what size should i get for the mods on the bike. Does anyone know a good place to buy just the jets, instead of a dynojet kit for 120.00?

 

I think I remember seeing K&N making jet kits for sport bikes, maybe you should look into it.