CR cylinders similar to current YZ's?

[skipn8r]

I have an '01 CR250 engine that runs great. But it doesn't seem to have the bottom end of a new YZ engine. Does anybody know which of the '92 - '01 CR250 cylinders has port timing (and power characteristics) most similar to a current YZ250?

 

[76GMC1500]

My 87 has some good bottom end, maybe you should consider riding one of those. The bottom end is like riding an XR400. The top end is like riding an early 4-stroke motocrosser. It's an interesting engine.

 

[darringer]

Of the '92-'01 cylinders, the '99 has the best stock porting for strong bottom. They do tend to run flat up on top though. I had to short-shift to get the most out of the motor. It was very good for the trails and for hillclimbing.