I am a novice rider and was wondering if i should buy a 4 stroke or stay with 2. I ride like 2 times a week (around 4-6 hours track time) and was wondering if a CRF250r would bankrupt me in maintenance costs. A 2 stroke i can take care of most of the major rebuilds myself but i have never attempted it on a 4 stroke so i would probably have a dealer do any top end rebuilds. If i check the valves often can i get away with a top end rebuild once a season ?(10 months NYC). Or would i need to have it done more often Thanks for any opinions