Hi! I'm a new member thats looking at getting either of these two bikes. both are in good condition! The YZ is $428 cheaper than the CR (I live in SA so i converted the difference in to dollars)... I have only ever ridden a YZ125 and recently an old WR250 (both 2-stroke). I'm unsure on whether to stick to 2-stroke or shift to 4-s? I want to start racing in open motox races but i usually just ride socially. Any advice would be great!