261.5cc stock cylinder vs. 297cc 250R

[machwon]

68mm stock cylinder with ESR 5 pipe, 40.5mm carb, race cut stock head and cr ignition vs. 72.25 pro-x cylinder ESR 5 centermount pipe, 40.5mm carb, ESR race dome and cr ignition.

[8686]

Bob, did you build, port, and set up both of these engines? How aggressive would you say each set up is? Thanks for posting.

[machwon]

Tim, yea I ported and set up both of these motors. Both motors were ported between the dune and drag port, so yes fairly aggressive.

[chronicsmoke]

good numbers, thanks for posting.

How would your dune/drag porting perform in the bush or on a track? Would it be too aggressive?

[machwon]

chronicsmoke, it will really depend on the rider. The power curve is rather broad, but with that much power some complain of too much wheel spin and therefore associate the motor with a light switch powerband. The graph obviously shows otherwise. I have presonally used this motor build for my all around R on trails, dunes and at a local mx track for practive.

[Langbolt]

Which is which ? I'm assuming the 297 is the RED and the 261 is the blue....Just wanted to clarify

Thanks for Posting

:D

[machwon]

Yes, the red line is the 297 motor.