Fifty years ago, Honda changed the world of motocross with its 1973 CR250M Elsinore. Now, for 2023, Honda is celebrating those 50 years with a special edition of the CRF450R motocross bike. Let’s take a look at some historic highlights of Honda’s CR/CRF line before checking out what’s new for this year.
A Brief MX History
The original Elsinore, a 250cc air-cooled two-stroke single, was a light, lean bike, quite advanced for the time, though of course it’s decidedly vintage-looking today. Motocross was undergoing an explosive period of growth, and by 1981, Honda introduced its all-new CR250R, a machine which featured a much improved engine and chassis.
This was followed in 1985 by the mighty CR500R, an open-class liquid-cooled two-stroke powerhouse that put out a staggering 52 pound-feet of peak torque.
A radical evolution came in 1997 with the introduction of Honda’s twin-spar aluminum chassis. Five years later Honda took its next huge step forward with the 449cc four-stroke CRF450R, which was extremely advanced for the time with its unique compact SOHC four-valve cylinder head and a second-generation aluminum frame. The engine’s peak power numbers were in line with the two-stroke CR250R, but with a much fatter torque curve.
The next step, in 2009, was adding fuel injection, with a 50mm throttle body replacing the carburetor. The engine gained both power and tractability, while riders could tune both fuel delivery and ignition thanks to a special HRC kit. The chassis continued to evolve, relocating the engine lower for better weight distribution and a more compact general construction.
In 2019 the engine received an electric starter, and HRC developed a cylinder head that improved both torque and peak power. The bike also received HRC launch control. In 2020 the three-level Honda Selectable Torque Control (HSTC) gave the rider options to manage traction.
The New 2023 CRF450R
And so we find ourselves in ‘23, looking at the 50th Anniversary Edition of the CRF450R.
The mechanical revisions this year are aimed at making the bike easier to push to its limits and to allow the rider to go faster with less effort. Honda’s done this by rebalancing both peak power and low-end torque. The 96mm by 62.1mm bore and stroke remain unchanged, as does the Unicam valve gear. Compression ratio is a solid 13.5:1, but for 2023 HRC developed new cam profiles and new valve springs, along with some other major induction revisions. The inlet runners are longer, with a new profile and a smaller diameter to increase the intake charge speed. To that same point, the throttle body has a smaller diameter than the previous model, shrinking from 46 to 44 millimeters, again with the intent of speeding up charge velocity. As a result, the engine generates a claimed 10.7 percent more torque at 5,000 rpm at the cost of a 5 percent reduction in peak power. Honda figures, as do many riders, that this fatter midrange makes the bike easier to ride and aids in acceleration out of turns.
The chassis has also been revised to generate more precise steering response, more stability, and better suspension compliance. Frame rigidity has been increased by fine-tuning the thicknesses of the single-downtube joint and the rear shock’s upper mounts; the cylinder-head hangers have changed from aluminum to steel; the rear shock’s spring rate has been increased from 39.8 to 41.3 pounds per millimeter, and the shock has been revalved in accordance with the new spring ratio. The rear suspension offers 11-position rebound damping adjustability and six-position compression adjustment.
The new aluminum swingarm measures 23 inches center to center, while the wheelbase now spans 58.3 inches. A new 49mm Showa fork delivers a generous 12.2 inches of travel, with 13 adjustments for rebound damping and 15 for compression damping. Steering geometry is set at 27.1 degrees with 4.5 inches of trail. Claimed weight is 245 pounds wet including a full fuel load. Weight distribution front/rear is 49/51.
Electronic Rider Aids
As with streetbikes, electronic rider assistance systems are growing more popular on MX machines.
To that end, the CRF450R features a comprehensive electronics suite. Honda Selectable Torque Control (HSTC) lets the rider choose from three torque delivery modes to optimize the amount of wheel. HSTC Mode 1 intervenes more gently and after a longer interval; this is intended to make torque delivery easier to control out of tight corners. When set on Mode 3, HSTC comes in immediately and with a sharper cut of the torque to the rear wheel, better suited for riding on slippery surfaces. Mode 2 is of course the intermediate solution. Don’t want any interference from HSTC? Switching it off is also an option.
HRC Launch Control assists the rider at the start of a race, delivering maximum acceleration through the gears. Like HSTC, it also offers three levels: Level 1 is intended for professional riders and allows the engine to push up to 9,500 rpm; Level 2 cuts at the revs at 8,500 rpm and is intended for standard condition and average riders; and Level 3 drops the limit to 8,250 rpm to make life easier for novices. Finally, the electronics also include an Engine Mode Select Button (EMSB) allowing the rider to modify the character of the engine response according to three maps: Standard, Smooth, and Aggressive.
The 2023 Honda CRF450R has also been developed into the enduro/Baja-oriented CRF450RX. Most of the major componentry is similar; major differences are limited to an 18-inch rear wheel in place of the R model’s 19-inch hoop, and Dunlop Geomax tires in place of the standard Dunlop MX33s. The RX chassis also features different steering geometry and a slightly shorter 58.1-inch wheelbase. Suspension units and brakes are shared by the two versions.