Alright, i want to set my quad up for mx, i know the suspension im going with, but im interested in swapping the motor, I seen on here about the yz400,yz456,yz250,cr500, ect, i want something that has good aftermarket part offerings, makes Alot of power to whoop up on them shee and 450 owners. I got a mig,tig, plasma cutter so fabing mounts isnt gonna be hard. I just want something reliable makes the power that i want to hit triples and pull on strait aways,and something i can get good parts for. i had a 660r and that was pretty nuts. What year make and model engine? and how easy is it to get a hold of?Let me know the pros and cons of the motors.