Another stupid thread on CEG? Neverrrrrrrr!
Anyone who says that 600s are too slow really needs a punch in the sack. Come ride with me someday. I'll introduce you to a few people who will decimate just about anyone on this board on their 250cc, 80 HP, 2-Stroke. Bring your R1kZX10 if you want.
Get what you can afford to fix. You'll die just as easy on anything and certainly break lots of stuff.
