The 2020 Honda CRF250R and CRF250RX get most of the changes made to the CRF450 racing lineup, along with many much more significant 250-only updates. Let’s go over all the updates to the 2020 Honda CRF250R motocrosser and 2020 Honda CRF250RX off-road racing motorcycle.

1. The 2020 Honda CRF250R and CRF250RX get a new cam profile for the DOHC motor. To increase torque and horsepower on the top end—6000 to 10,000 rpm—the exhaust valves will be opening later for reduced valve overlap.
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https://ultimatemotorcycling.com/2019/05/07/2020-honda-crf250r-and-crf250rx-first-look-fast-facts/