Maybee even a rg500 motor, they are a little easier to get parts for. The only prob with this idea is that i race MX and it would make the already heavy shee heavier still, I might get a 450 then do it, if i did it that way I could use it for trail riding. Another Idea i have been thinking about, in an rgv250 motor. I already know a fair bit about them and they a a great motor.