Motorcycle specifications HondaCRF 450 RX 2017 Wings on the trail

How many years has it been since Honda last offered an enduro model in its official range? 10 years? Or even longer? For a long time, HM and then Red Moto were busy modifying and homologating CRs to satisfy the thirst of enduro riders. We're back, through the front door, with a 450 RX closely derived from the cross-country machine. It's ready to race with specific suspension, electronic fuel injection and engine mapping, a large-capacity fuel tank, an 18-inch rear wheel, a side stand and an original electric starter.

so for 2017, Honda has a brand-new competition machine in its off-road range, the enduro CRF 450 RX. This machine uses the engine and chassis of the 2017 CRF 450 R, the first complete redesign of this bike in eight years.

since its launch in 2002, the CRF 450 R has been considered one of the world's leading cross-country motorcycles.quilibrium between engine and chassis, with high but usable power, combined with a chassis that allows riders of all levels to make the most of every bit of that power. From the rider's point of view, whether amateur or competitor, the CRF 450 R has always been a machine offering both total control and the robustness and longevity for which Honda is renowned.

all these qualities made it the perfect platform for an enduro machine, giving the CRF 450 RX the DNA of a true motocross bike, in a way that allows it to be ridden in the most demanding conditions.all these qualities made it the perfect platform on which to build an enduro machine, giving the CRF 450 RX the DNA of a true motocross machine, so that it can tackle all types of enduro stages, from the fastest to the most extreme, with confidence and ease.

the CRF 450 RX is a truly special machine, not only for Honda but also for the world of enduro. It's completely new, its reactions are different, and the riding experience it offers is also different. And just like the new CRF 450 R, it's incredibly efficient.

mikio Uchiyama, head of development for the 2017 CRF 450 RX:

"The CRF 450 RX is an authentic competition enduro like Honda has never made before. It benefits from the high level of performance of the new CRF 450 R, and we've made no compromises in making this 'RX' version, which brings something completely new to specialists in this category. It's built to win right out of the box, and at the highest level of competition."

key features

the 2017 CRF 450 R has been developed with the direct support of the Honda teams engagedin the American AMA and European MX GP championships, with a new engine boasting 11% more power than its predecessor. The CRF 450 RX is virtually identical in every respect, but with a few crucial differences that make it a genuine enduro machine.

the front and rear suspensions are less firm, with softer compression damping and lower spring rate at the rear. It also features an 18-inch-diameter rear wheel, a side stand and an 8.5-liter fuel tank for greater autonomy.

mapping of the CRF 450 RX's PGM-FI electronic fuel injection system delivers more power and torque than ever before.power and torque characteristics than on the CRF 450 R to deliver a more precise feel for grip in difficult conditions. As on the CRF 450 R, the EMSB (Engine Mode Select Button) system on the handlebars allows the rider to choose between three different mappings: mode 1 for versatile performance, mode 2 for gentler throttle management, and mode 3 for more dynamic and instantaneous power delivery.

The electric starter is standard equipment.

detailed specifications

engine

the 449 cm3 single-cylinder engine of the CRF 450 RX shares the same characteristics as that of the new 2017 CRF 450 R, with maximum power up 11% on the previous model. Despite this, performance remains perfectly exploitable throughout the rev range. The volumetric ratio is set at 13.5:1, with fundamental bore x stroke values of 96 x 62.1 mm.

a new four-valve Unicam cylinder head with intake latch provides 10 mm intake valve lift, while exhaust valve lift is 8.8 mm. Intake valves have a diameter of 38 mm, while special machining of the valve seats facilitates gas flow. The configuration of the intake system ensures direct air access to the ducts.

In cross-section, the valve springs have an oval cross-section, resulting in reduced height and more compact dimensions. Valve angles are now narrower, at 9° and 10.5° respectively at intake and exhaust, compared with 10°/ 11.5° previously. A 4-nozzle oil jet replaces the previous two-nozzle model to reduce piston temperature and effectively manage the heat generated by higher compression.

to reduce frictional losses, the piston pin and timing pin receive a DLC surface treatment.receive a DLC (Diamond-like Carbon) surface treatment, a material with excellent longevity and abrasion resistance.

the motor uses a pump that distributes oil to the transmission and clutch under pressure rather than by vaporization, reducing friction, improving lubrication efficiency and limiting pumping losses. The oil capacity is 1,250 cm3 in a single sump that houses oil for the engine, gearbox and clutch.

the clutch has 7 lined discs and 6 smooth discs, each made of a special material. A 2 mm thick disc dissipates heat more efficiently, while an anti-dribble spring is fitted to maintain an effective connection with the clutch. The five gears of the gearbox are identical to those of the CRF 450 R, but the final drive is increased from 13 x 49 to 13 x 50.

the various rider controls are grouped together and positioned on the left hand side: ignition switch, EFI warning light, EMSB mode control, diode indicator and the original electric starter control, which makes starting much easier, especially in rocky terrain or on slopes.

honda EMSB (Engine Mode Select Button) is the key system for adapting engine character to rider demand. With the motorcycle static and the engine at idle, a simple press and hold on the dedicated switch for 2 seconds selects the next map in the sequence.

after a quick press, the LED on the switch indicates the current map: one flash for mode 1, 2 flashes for mode 2... If a new map is selected, the choice is also confirmed to the driver three times.

mode 1 is the standard mode, offering the most linear response to throttle opening, making the engine's power even more exploitable in a wide range of conditions. Mode 2 softens the engine's performance (a particularly welcome choice when you're tired), while mode 3 offers more responsive behavior, with more aggressive and instantaneous power, just like mode 1 on the CRF 450 R.

this is a genuine competition engine, and therefore requires regular maintenance. However, maintenance is straightforward, with oil change, oil filter change and valve lash adjustment every 15 hours. The engine does not need to be completely opened and reconditioned after a certain period of use.

cycle

The CRF 450 RX uses the 7th-generation double-beam aluminum frame, whose performance has been improved in terms of stability, rigidity and rigidity.performance has been improved in terms of front-end stability, rear grip and cornering agility. The new frame also improves rear-end steering, with a high level of feedback to the rider.

the main visual change is in the beams, which are now trapezoidal in shape, resulting in greater front-end stability, grip and feel. The lateral rigidity of the previous frame has been retained in its entirety, but torsional rigidity has been reduced by 6.8% to improve cornering ability and feel. All in all, the new frame weighs 9.14 kg, with the extruded aluminum rear buckle weighing 1,045 gr.

several subtle changes have been made to the geometry and dynamic parameters of the CRF 450 R frame. The center of gravity is lowered by 2.7 mm, the wheelbase is 1,477 mm, the distance between the front wheel axle and the swingarm axle is increased by 13 mm to 913 mm, while the distance between the swingarm axle and the rear wheel axle is only 564 mm. This new geometry transfers more weight to the rear wheel for improved grip.

the 959 mm seat height, caster angle and drag are set at 27.4°/116 mm, while the total weight is 118 kg.

the CRF 450 RX is a slim, compact and easy-to-operate machine, thanks to a very low center of gravity. Its geometry loads the rear tire for better traction, in line with the superior grip and feel claimed by the front axle, especially when approaching the limit.

the new CRF 450 RX is equipped with a "factory-style" inverted fork with ø 49 mm springs, a fully adjustable version derived from the kit supplied by Showa to official teams competing in the Japanese MX championship. The cartridge is 25 mm in diameter, with a ø 14 mm stem and a ø 39 mm secondary cartridge. As you'd expect from a suspension designed specifically for racing, the ride is smooth and progressive, offering total control.

compared to the CRF 450 R, the CRF 450 RX's fork uses less oil, with softer compression damping to deliver smoother reactions, and is more suited to versatile off-road use.

fully adjustable, the Showa rear shock absorber is positioned low and in line with the machine for optimum mass centralization and high-speed stability. Its setting is 52 N/mm (54 N/mm on the CRF 450 R), with an even softer compression damping. The result is smooth control.

at 599 mm long, the swingarm is 18 mm shorter than that of the 2016 CRF 450 R, with thinner arms.

at the front, a ø 260 mm petal disc combined with a 2-piston caliper ensures braking that's both powerful and easy to control. at the rear, it's complemented by a ø 240 mm disc with single-piston caliper. Aluminum rims (21 x 1.6 at the front and 18 x 2.15 at the rear) limit unsprung weight, and are fitted with Dunlop Geomax AT81 90/90-21 at the front and 120/90-18 at the rear.

an 8.5-liter plastic fuel tank provides good autonomy. Thinner, lighter cylinder-head mounts compensate for the extra weight of the tank and fuel. New, soft-lined plastic trim helps the rider to move around the machine with ease, the front end being particularly narrow, with a width of just 410 mm at the radiators and scoops. Last but not least, the shape of the front mudguard efficiently directs air to the radiators.

the forged aluminum side stand does not impede movement, and is secured to the frame at the level of the left footrest by a stainless steel bracket. As on the CRF 450 R, the cladding features new graphics covered by a resistant film that covers a large part of the surface.

News and media credits: Honda