DESCRIPTION:

NINE-PLATE CLUTCH ASSEMBLY

The CRF250RX uses a nine-plate design to improve durability and hookup. That means less slip at peak horsepower, better torque transmission through the clutch pack and greater durability. Plus, the clutch pull is lighter, and you get improved engagement feel.

DOHC ENGINE LAYOUT

The CRF250RX uses a double-overhead-cam (DOHC) engine layout with a unique finger-follower rocker design. Together with the rest of the engine’s architecture (bore and stroke, intake tract, piston, and more), you get more power and a higher redline.

BIG BORE/SHORT STROKE

The CRF250RX’s 79mm bore and short 50.9mm stroke let our engineers create a high-revving engine with plenty of room for large valves. The engine breathes and revs—the two keys to making power in the enduro world.

DOWNDRAFT INTAKE AND EXHAUST LAYOUT

The DOHC cylinder-head design let our engineers straighten out the CRF250RX’s intake and exhaust tracts. The intake is shorter and just about arrow straight, and the exhaust flows more efficiently too. The straighter ports also help boost low-speed and midrange torque as well as throttle response.

SINGLE-MUFFLER EXHAUST

Using a pressed-alloy design lets us shape the muffler for better rider ergonomics and lighter weight.

SINGLE-PIPE EXHAUST

Along with the single-muffler exhaust, the CRF250RX naturally uses a single-pipe header. It routes close to the center of the bike, and its light overall construction helps improve weight distribution.

WIDER WATER-PUMP DRIVE GEARS

Making the water-pump drive gear wider gives it more tooth-engagement area for longer component life.

UPGRADED CAM OILING

To help improve durability, we’ve re-routed the cam’s oil supply, as well as giving the CRF250RX a more rigid cam holder—better roundness and more oil means less friction and wear.

ENGINE MODE SELECT BUTTON

This simple handlebar-mounted button lets you dial in engine power delivery character with a push of your thumb. Choose between Standard, Smooth and Aggressive, depending on course conditions.

ENGINE OIL SCAVENGE PUMP

Deep in the engine, there’s a special oil scavenge pump that we’ve designed to be especially small and out of the way. While you may never see it, it helps keep the CRF250RX’s overall design compact.

SPECIAL PRIMARY AND TRANSMISSION RATIOS

To handle the fatter midrange power and torque, the CRF250RX gets special primary and transmission ratios. The ratios let our engineers use the same shaft centerlines as the previous design, so the transmission itself remains light and compact.

TWO-LEAD SHIFT DRUM

By changing from three to two lead tracks on the shift drum last year, we improved the shift feel between second and third gears.

GEAR-POSITION ENGINE MAPPING

Talk about smart: The CRF250RX features an ECU with special engine mapping for each gear. You can’t give an inch in this class, so having your engine deliver optimal power for each gear choice is one of the features that separates CRF250RX riders from the rest.

"H" SECTION CRANK

Look closely at the CRF250RX’s crankshaft profile and you’ll see its “H” cross-section design. Just like a structural “I” beam in an aircraft wing or a skyscraper, it boosts strength and cuts weight over a conventional crank’s shape—a big deal when you consider this part spins at over 14,000 rpm!

HIGH CAPACITY RESIN FUEL TANK

For longer enduro loops, the CRF250RX features a large resin fuel tank that holds over two gallons.

LITHIUM-ION BATTERY

Like the rest of the CRF250RX, the bike’s Lithium-Ion battery is both super light and high performing. In fact, it weighs less than half the weight of a conventional lead-acid battery.

SHARED ENGINE/GEARBOX LUBRICATION

The 2024 CRF250RX uses a shared engine/transmission oiling design. Combining the two systems shaves weight and helps make the engine more compact, especially when it comes to placing the right-side cam drive and the clutch so close together.

TITANIUM INTAKE AND EXHAUST VALVES

Light is right when it comes to a high-revving engine’s reciprocating masses. That’s why the CRF250RX uses titanium intake and exhaust valves with a super-narrow 20.5-degree included valve angle. Ovalized valve springs and long-wearing Diamond-Like Carbon (DLC) treated finger rockers complete the package.

TOTAL AIR MANAGEMENT

Total air management means complete attention to how efficiently air gets through the intake, through the head, and out the exhaust. Eliminate losses here, and you make more power everywhere. And the best part: It’s free horsepower—you just need a bike with smart design.