Motorcycle specifications HondaCRF 250 RX 2019 Enduro de pointe

Enduro makes its way back to Honda. The all-new CRF 250 RX joins Honda's 2019 off-road line-up with its enduro design and features. While it shares its frame and main engine components with the cross CRF 250 R, it is perfectly adapted to its vocation with an 8.5-liter fuel tank, forged aluminum kickstand, 18-inch rear wheel and specific engine mapping and suspension settings. The new CRF 250 RX also features a three-mode Launch Control system directly inherited from the racing department.

key features of the Honda CRF 250 RX :

like the CRF 450 RX, the CRF 250 RX takes the proven base of the Cross version and adds all the ingredients needed for enduro use. It features an 8.5-liter fuel tank (like the CRF450RX), an 18-inch rear wheel, a forged aluminum stand and revised front and rear suspensions. Ignition and injection mappings have also been adjusted to deliver a smoother power delivery compared to the cross-country version.

the CRF 250 RX also benefits from all the improvements made to the 2019 CRF 250 R model: engine upgrades with extra low-end torque for better cornering (thanks to work carried out all along the intake line, from the throttle body to the exhaust), new front brakerenthal Fatbars handlebars and, above all, a 3-mode Launch Control system, directly inspired by the one used by HRC, to help the rider - whether beginner or expert - to extract himself instantly from the starting line.

let's take a closer look:

motorization

the most important thing for the engine specialists in charge of developing the 2019 CRF 250 R was to maintain their engine's beautiful power at the revs (+9% in 2018 vs. the 2017 version) but also, at the same time, to optimize low-end torque so that the bike emerges even better from tight corners.

this objective has been achieved at the cost of a number of evolutions, starting with a slightly different intake manifold.starting with a slightly smaller-diameter intake manifold (-2 mm to 44 mm) to accelerate the gas flow at low revs. The intake and exhaust ducts have been redesigned, while the closing profile of the exhaust cam has been reduced by 2° to improve torque.

the CRF 250 RX therefore benefits from the evolutions and performance of the 2019 engine - in particular its maximum power - but is distinguished by modified ignition and injection mapping to soften its behavior.

the fundamental bore and stroke dimensions are set at 79 x 50.9 mm, with a cylinder offset of 4.5 mm to reduce friction. The volumetric ratio is 13.9 to 1. The valves, whose springs have an oval cross-section, are made of titanium, ø 33 mm at the intake and ø 26 mm at the exhaust, with lifts of 10.5 mm at the intake and 9.5 mm at the exhaust. The angle between the valves remains fixed at 20.5°. Finally, the intake valves benefit from 2 vertical symmetrical ducts which are now shorter to improve responsiveness at high revs.

the piston, which has been reinforced in the form of a partition, converts the pressure resulting from combustion of the mixture into pure power even more efficiently. As on the Cross version, a five-nozzle oil nozzle replaces the previous 4-nozzle model to optimize piston cooling. Ignition maps have also been reworked.

the oil pump reduces friction and pumping losses at high engine speeds by evacuating air and oil from the crankcase and maintaining negative pressure. The engine oil, with a total volume of 1250 cm3, also lubricates the clutch and gearbox.

the primary pinion (which drives the oil pump), filter and oil lines are located on the right-hand side of the engine, making the lubrication circuit shorter and more direct. Distribution lubrication now passes through the cylinder head to the inside of the intake and exhaust camshafts, directly lubricating the contact surface between the rocker arm and the valve stem.

as for the transmission, the 5-speed gearbox drives an O-ring chain with a final gear ratio of 13 x 48.

the ignition switch, EMSB (Engine Mode Select Button) map selector, injection warning light and LED are integrated into a small comodo on the left of the handlebars.

borrowed from the 2019 CRF 250 R, the HRC-developed "Launch Control" start-assist system allows riders to choose from three start modes:

- Mode 3 / 8,250 rpm, particularly suitable for beginners and/or muddy conditions
- Mode 2 / 8,500 rpm, for advanced riders and dry conditions
- Mode 1 / 9,500 rpm, for expert riders and dry terrain

activating the Launch Control system is simple: just activate the clutch and press the starter button. An LED will flash once to indicate that mode 1 is active. If the starter button is pressed a second time for 0.5 seconds or more, the LED will flash twice to indicate that mode 2 is engaged. Press again and the LED will indicate that mode 3 has been selected.

at the same time, the EMSB (Engine Mode Select Button) map selector is used to adjust engine characteristics. 3 mappings are available to suit rider preferences and riding conditions: Mode 1 (Standard), Mode 2 (Gentle) and Mode 3 (Aggressive). The same LED also informs the rider of the selected mode.

cycle part

the CRF 250 RX uses the same double-beam aluminum frame as the CRF 250 R, a component that guarantees excellent feedback and optimum rear-wheel grip thanks to a low center of gravity.

globally unchanged from the Cross, the RX's chassis benefits from a new, lighter front brake caliper, with ø 27 and 30 mm pistons as opposed to 2 x 27 mm in the past. This evolution, combined with the adoption of a new low-expansion hose, improves braking feel and maintains power at a constant level. The new caliper acts on a ø 260 mm petal disc, complemented at the rear by a ø 240 mm disc with single-piston caliper.

renthal Fatbar handlebars help reduce steering weight, while increasing rider comfort thanks to their flexibility. The fork crown is designed so that the handlebar mounts can be moved 26 mm forwards or backwards. When the mounts are rotated 180°, the handlebars have an additional 10 mm of latitude, bringing to 4 the number of positions available to the rider.

caster angle and drag are set at 27.3°/115 mm, while the wheelbase is 1,486 mm. Kerb weight is 111 kg.

the Showa inverted fork ø 49 mm with springs is simply a version of the Showa factory kit supplied to official Japanese MX Championship teams. The main rebound cartridge is 25 mm in diameter, the stem ø 14 mm, while the secondary cartridge for managing compression is a 39 mm model. The Showa rear shock absorber is fully adjustable.

the DID aluminum rims (21 x 1.6 at the front and 18 x 2.15 at the rear) are now black anodized. Both are fitted with Dunlop GEOMAX AT81 Enduro 90/90-21 and 110/100-18 tires.

like the CRF 450 RX, the 2019 CRF 250 RX features an 8.5-liter plastic fuel tank. The radiator gills are specific, with a shape that allows the rider to move around the machine easily, while the narrowness of the front end and the shape of the front fender direct air more effectively to the radiator. Further back, the forged aluminum kickstand folds away discreetly when not in use.

the trim decoration is integrated directly into the plastic components, ensuring high resistance to friction.

finally, the engine cowling and fork protectors have been redesigned, the former to facilitate engine cooling, the latter to reduce damage in the event of impact.

News and media credits: Honda