Yamaha has refined its distinct rearward-slanted cylinder design for the 2018 YZ450F engine – complete with a rear exhaust and forward-mounted downdraft intake system.
Watch Adam Cianciarulo's Main Event from round 17 of the 2017 Monster Energy Supercross Series in Las Vegas, Nevada.
Enjoy the carnage from the Revlimiter Extreme Enduro, held in Bridgeport, Texas, in hot, testing conditions.
Watch the full race replay of the 450cc Main Event from Rd5 of the 2016 AMA Supercross series at Phoenix.