For 2009, Honda shook up the off-road motorcycle world with the introduction of its radically changed CRF450R motocross motorcycle. This dirt bike signified a new direction for Big Red, incorporating many fresh features designed to increase its prowess around the racetrack. While there were certain aspects of this next generation CRF that we loved, there were also a few characteristics that we were less than enthused with. Honda has answered by fine tuning and delivering us an updated 2010 Honda CRF450R. Although the changes are minimal, they do equate to a better experience on the dirt—but did Honda do enough? We spent a morning riding at Southern California’s Race town 395 to find out the truth?
This year’s engine got a significant overhaul and remains essentially the same. The water-cooled lump still displaces 449cc via a 96.0 x 62.1mm cylinder measurement. Fuel is compressed to a respectable 12.0:1 compression ratio. Honda’s proprietary Uni cam design ensures a compact cylinder head by using a solo camshaft to actuate the mixed titanium/steel valve train.
he intake system uses a 50mm throttle body and a single 12-hole fuel-injector that is powered directly by the bike’s AC generator. Exhaust exits in an aesthetically pleasing stainless-steel header that wraps back into a short muffler on the right-hand side of the bike. The engine is paired with a 5-speed transmission augmented through cable-actuated clutch. Power is transferred to the rear wheel via a chain final drive that utilizes 13/48 gearing.
Maintenance and vehicle upkeep was also one of the areas engineers originally focused on. The engine retains its signature twin-sump lubrication system with separate engine and clutch/transmission reservoirs which reduces mechanical power losses and lengthens oil service life. Furthermore, the airbox features a larger opening which makes it easier to service the filter. The fuel tank also has a clever rubber tether so the top-end can be serviced without disconnecting it.
One of the features we appreciated the most in last year’s bike was the engine. (Read the review in our 2009 450 Motocross Comparison.) When tested it was extremely flexible, offering the riders the best of both worlds; bottom-end power delivery was soft, however it seamlessly morphed into a civilized, yet robust mid-range and a respectable top-end, only marginally off the class-leading Kawasaki.
For 2010, Honda has updated both the fuel and ignition maps, further enhancing an already friendly power band. The new mapping is also said to aid in starting via a revamped auto-engine-decompression system. While the ’09 bike was definitely finicky to start, we’re pleased to report that this trait has been eliminated with the ‘10 machine.
“Getting the engine fired was kind of a pain before,” states MotoUSA’s resident pro-level test rider Matty Armstrong. “It definitely took a couple of kicks before, but they’ve fixed the problem and now it fires right up on the first kick.”
