Twin Pipes, Electric Start & More. The 2018 Honda CRF250R Is Just Like We Said It'd Be.
Back in May, TransWorld Motocross traveled to Hiroshima, Japan, to get a first look at the all-new 2018 Honda CRF250R as it was being race-tested in Japan by Takeshi Katsuya in the IA2 class of the All Japan National Championships. We were tipped off several weeks prior that the bike Katsuya would be racing was a pre-production version of the machine that would land on dealership floors this fall, and lo and behold…the 2018 CRF250R looks to be exactly like the machine we showed you several weeks ago! Here are the official details from Honda…
The “Absolute Holeshot” philosophy that helped revolutionize the latest-generation CRF450R now makes its way to the all-new CRF250R, a model that has earned no fewer than nine AMA Supercross championships and two AMA Motocross championships over the years. Updates are aimed at achieving maximum power (particularly at high revs) and superb handling, the vastly updated four-stroke engine now featuring a dual-overhead-cam design, twin exhaust ports, and more oversquare dimensions. Mass is lower and more centralized, through vehicle-packaging updates like a titanium fuel tank and extruded-aluminum subframe brackets, while a lighter aluminum frame with optimized flex characteristics helps handling and rider feedback. An electric starter, powered by a lightweight lithium-iron phosphate battery, is now standard.
In order to achieve their powerplant development goal of increased power (particularly at higher revs), engineers gave the 249cc engine an all-new dual-overhead-cam design, using a finger rocker arm with Diamond Like Coating (DLC). The titanium intake and exhaust valves are larger and have a higher lift and narrower angle, while the valve springs’ coils now have an oval cross-section to keep engine height as low as possible. The engine has more oversquare dimensions, the cylinder offset has been increased, and the piston now features a bridge-box design–a first for a production Honda motocrosser. The intake system is now of a downdraft design for maximum efficiency, there are twin exhaust ports, and the dual exhaust features smoother routing and optimized pipe length. An electric starter is standard, powered by a small, lightweight lithium-iron phosphate battery. The end result of the copious changes is an engine with more power across the rev range, especially impressive at peak rpm.High-performance, 249cc single-cylinder engine with dual-overhead-cam design and higher rev limit.
- Cylinder offset changed from 4mm to 4.5mm for reduced friction.
- Finger rocker arm with Diamond Like Coating (DLC) maximizes valve lift while retaining a low engine height.
- Optimized bore and stroke, larger valves, and a narrower valve angle contribute to increased power and a higher redline.
- Oval-section coils on valve springs allow for increased valve lift while retaining a low engine height.
- Bridge-box piston converts combustion pressure to power with higher efficiency.
- Larger piston jet oil hole for weight reduction and reduced friction.
- New scavenging pump reduces pumping loss.
- Crankshaft with H-shape cross section enables weight reduction without sacrificing rigidity or inertial mass.
- Downdraft intake layout increases power and improves throttle response by reducing resistance, improving air-charging efficiency.
- Shorter intake length improves high rpm engine power and acceleration feeling.
- Dual exhaust ports improve air-charging efficiency.
- Compact dual muffler with more-gradual pipe bends smoothen exhaust flow.
- Electric-start standard for easy starting.
The 2017 CRF450R set new standards for vehicle packaging in a motocross machine, with highly concentrated mass and a very low center of gravity; the 2018 CRF250R follows suit, with weight reduced overall but particularly up high and at the ends of the vehicle. Layout is slim and low, and the machine has superb rear-wheel traction but minimal front-end lift–ideal for strong starting and acceleration. The main spars of the new-generation, lighter aluminum frame are now tapered to optimize flex characteristics and provide good stability and reliable rider feedback, while a shorter wheelbase improves overall agility. An all-new titanium fuel tank and extruded subframe end save precious weight up high, a new Showa coil-spring fork contributes a plush suspension feel, and a lower, more centralized shock location improves stability. Bodywork mirrors the design of the CRF250R’s bigger brother in form and function, with a minimalist appearance and in-mold film graphics. Dunlop’s superb Geomax® MX3S tires are standard.
- Shorter wheelbase for lighter handling.
- Lower center of gravity reduces front-end lift and contributes to better acceleration performance.
- Reduced swingarm length improves rear-wheel traction
- Lightweight aluminum frame with tapered main spars improves rider feedback.
- Extruded-aluminum subframe brackets contribute to reduced weight and lower center of gravity.
- Titanium fuel tank contributes to reduced weight and lower center of gravity.
- Showa coil-spring fork enhances plush suspension feel.
- Lower, more centralized shock location improves stability.
- Dunlop Geomax MX3S tires for superior bump absorption and grip in wide variety of conditions.
- Smooth bodywork layout eases rider movement.
- In-mold film graphics for added durability.
- Carefully shaped front fender allows efficient air path to radiator.
- Consult owner’s manual for optional racing parts
- Specifications subject to change
- More over-square bore/stroke dimensions
- Increased valve size/lift, narrower valve angle, oval cross-section valve springs
- Higher compression ratio
- Downdraft air intake
- Dual exhaust ports/headers/exhausts
- Electric start
- Lighter frame/subframe with optimized flexibility characteristics
- Revised chassis geometry for lighter handling, improved rear traction, reduced front-end lift
- Coil-spring fork
- Titanium fuel tank