The Honda CRF450R

For 2010, Honda tweaks its new generation CRF450R motocross platform.The Honda CRF450R uses a twin-sump lubrication system with separate engine and clutch/transmission reservoirs which reduces mechanical power losses and lengthens oil service life. Last 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 Unicam design ensures a compact cylinder head by using a solo camshaft to actuate the mixed titanium/steel valvetrain.
Powertrain updates for 2010 are limited to a revised auto engine decompression set-up and new fuel and ignition maps. Together these changes make the CRF450F’s engine start on the first kick.The 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.The CRF450R’s ergonomics are well thought out for Armstrong’s 5-foot, 8-inch frame. This new generation CRF says hello to a radically altered chassis. It’s highlighted by a fifth iteration of the twin-spar aluminum frame that engineers designed with three things in mind: nimble handling, compact shape, and minimal weight. The biggest change is the steering head and front wheel being repositioned closer to the rider. Also, the space between the fork tubes and the steering head (triple clamp offset) was reduced down to 20mm, making the bike much easier to steer.A Kayaba 48mm AOS fork graces the front end. Honda’s Unicam solo camshaft design ensures a slim cylinder head. The space between the fork tubes and the steering head (triple clamp offset) was reduced down to 20mm, making the bike much easier to steer.The new generation CRF450R proves to be very sensitive to rider sag. Honda recommends between 104 and 108mm. The CRF450R is the lightest 450cc motocross bike on the market and you can feel its lack of weight in the air. The suspension balance front-to-rear still feels off on the 2010 Honda CRF450R. There are certain aspects of the CRF that we really dig. The updated fuel injection and ignition mapping has delivered an even more civilized engine that can be appreciated by all level riders. Although power feels softer initially as compared to its competitors, simply give the throttle a harder tug and within a split-second that thought vanishes faster than … well, you get the point. It’s also extremely easy to start now. It feels light both on the ground and in the air, plus it is exceptionally agile in slower turns. Not to mention the bodywork and some of the other hard parts are interchangeable with the all-new CRF250R . Here, Armstrong lofts the rear wheel into the corner proving the effectiveness of the CRF450R’s braking components.Everywhere else, though, it lacks stability, which ultimately limits how fast you can lap. Armstrong surmises it best: “The funny thing about the Honda is that its ergonomics are spot-on for a rider of my size, yet the suspension isn’t. The fork feels about right, but the rear shock is just way too stiff. If Honda could balance it out better I think they’d have a much better bike.”
The 2010 Honda CRF450R costs $500 more than the 2009 model and will be available in February, 2010 for $8099.
2010 Honda CRF450R Specs
Engine: 449cc liquid-cooled Single, SOHC, 4-valves Bore x Stroke: 96 x 62.1mm
Compression Ratio: 12.0:1
Fuel Delivery: Fuel-injection
Clutch: Wet multi-plate, cable actuation
Horsepower (2009 model): 48.1 hp @ 8100 rpm
Torque (2009 model): 31.8 lb-ft @ 7900 rpm
Transmission: 5-Speed
Front Suspension: Kayaba AOS 48mm fork, 16-position compression and 18-position rebound damping adjustment; 12.2 in. travel
Rear Suspension: Pro-Link equipped Kayaba, 20-position low-speed and step-less high-speed compression damping, 18-position rebound damping and adjustable spring preload; 12.6 in. travel
Recommended Rider Sag: 104 - 108mm
Front Brake: 240mm disc, double-piston caliper
Rear Brake: 240mm disc, single-piston caliper
Handlebar: Renthal
Tires: Dunlop D742FA 80/100-21, D756 120/90-19
Curb Weight: 237 lbs. (ready to ride)
Wheelbase: 58.7 in.
Length: 86.0 in.
Width: 32.7 in.
Ground Clearance: 13.1 in.
Seat Height: 37.6 in.
Fuel Capacity: 1.5 gal.
MSRP: $8099 Red, Avaliable February, 2010