No.1 for me was the SDG seat. No more slipping off the back! No.1.5 braided brake line.Improved the stopping power by 100% No.2 was yoshimura pipe. Aussie wr pipe is very restricted. No.3 suspension revalve and shock spring. No.4 fuel screw. For fine tuning. No.5 works connection clutch lever.Its a lot lighter. No.6 yz timing and home made powernow.450/426 riders are amazed with the Snap!