I have just bought a new 08 yz450f,i love trail 。I don't want take any competition, just for fun,so I need to reduce the power,and of course my yz450f engine would be more reliable. so i want to: 1.add a GYTR Off-Road Flywheel; 2.Replace my 08 yz450f exhaust cam with a 08 WR450 exhaust cam,not replace the intake cam. If just replace with a WR450 exhaust cam,need any jetting? Do I need to replace both intake cam and exhaust cam? Will the WR450 cam's Auto Decomp system cause my yz450f startup harder? grayracer513 could give any advice? thanks very much.