Well I only have 2 miles on the Bill Blue Big bore kit and all I can say I is Holy Sh*t! 1. The quality of his work is Fantastic. 2. The power change is unbelievable. I believe If Kawasaki built this bike with a pumper carb- and a 331 bore they could double there sales. Pulling away from my house the front wheel was coming up in 1st-2nd and 3rd gear! Its one of the best mods I have made in the power department!!! Stop waiting and do it. you will be glad you did.