CRF engine vs 450R engine

[Dale512]

I have a few questions concerning differences between the CRF and 450R engines.

What are the Cam Specifications for each motor? ie Lift, Duration, etc.

Valve Sizes?
Flywheel Weights?
Revlimit?

Thats pretty much it.

Thanks.

[xsr_racing28c]

kinda off subject, but did you ever round up that picture and time slip for your 9 sec sti?? thanks

[benwa450r]

There are several differences in engines. CRF has 2-ring 12:1 comp. piston where TRX has 3-ring 10.5:1 piston. Exhaust valves on CRF are 31mm where TRX are 30mm and intake valves CRF are titanium and TRX are steel. CRF has FCR carb and TRX has regular carb. TRX has beefier gears and double bearings on output shaft that CRF does not. CRF has higher rev limiter (around 1000 more) than TRX I think. This is off the top-of-my-head. Hope it helps.

[dn1911]

one of the big things is that the Head is shaped differently also. this is one of the big reasons for the power differences.