2007 HONDA CRF250R
New for 2007
- New camshaft and cylinder-head porting improve power output above 8000 rpm.
- New intake valve springs match new camshaft.
- New crankcase venting for improved engine power.
- New exhaust header works in conjunction with new camshaft.
- New carburetor features new-styled accelerator pump and linkage for improved throttle response.
- New clutch basket features increased thickness for additional strength.
- New ignition map with 13,370-rpm rev limit.
- New link-type front brake master cylinder improves front braking power by 15 percent.
- New Dunlop 742FA front tire provides improved turning feel and traction.
- New one-piece cover protects throttle cable by keeping out dirt and water.
- Lighter rear chain guide.
- New front suspension valving for improved bump absorption.
Engine/Drivetrain
- Powerful four-stroke 249cc liquid-cooled four-valve Unicam(R) engine is designed to produce power across a wide rpm range for easy-to-
control operation. - Lightweight, compact, internal auto decompression and handlebar-mounted hot-start system provide superb operation, hot or cold.
- Compact, lightweight engine assembly weighs only 52.7 pounds.
- Unicam valve train provides the light weight of a compact single-cam drive and the optimum combustion chamber shape for maximum power at all engine rpm.
- Unicam valve train features a carburized single camshaft that directly actuates two 31mm titanium intake valves. The camshaft exhaust lobe actuates two 26mm steel exhaust valves via a forked, low-friction roller rocker arm.
- Lightweight titanium intake valves permit the use of smaller valve springs, reducing overall engine height.
- Crankshaft is made of high-strength, low-carbon steel with carburized main journals for maximum durability at sustained high-rpm operation.
- ACG cover, clutch cover and cylinder-head cover are made of magnesium to reduce engine weight.
- Forged 12.9:1 compression slipper piston and rings are lighter than a conventional design, revving quickly while maintaining excellent cylinder sealing and high-rpm power.
- Double-carburized connecting rod utilizes a big-end needle bearing for maximum high-rpm performance and durability.
- Nikasil cylinder lining is lightweight and provides cooler operation for extended engine life.
- Press-fitted aluminum spark-plug pipe fits between forked exhaust rocker arms, further contributing to compact cylinder-head design.
- 40mm Keihin FCR carburetor features four rollers on the flat slide, resulting in very light throttle effort, smooth operation, crisp throttle response and excellent rideability.
- Carburetor features a throttle position sensor (TPS) that helps maintain a linear throttle response throughout the range.
- Twin-sump lubrication system separates the oil supply for the crankshaft, piston and valve train from the clutch and transmission. This ensures a cool supply of oil to the clutch, eliminates clutch and transmission material contamination to the engine oil, reduces the amount of circulating oil and permits the use of a smaller oil pump.
- Vertically split crankcases feature a built-in oil pump, reducing weight compared to a conventional design.
- Dual-muffler exhaust system centralizes mass and reduces turning inertia to improve the lightweight feel of the bike.
- Dual-muffler exhaust system also increases low-rpm torque.
- Exhaust system uses a lightweight stainless exhaust header and repackable aluminum mufflers.
- Dual radiators feature a refined core area for improved heat dissipation compared to conventional dual-radiator design.
- Gear-driven balancer reduces vibration and drives the water pump. Eight clutch discs provide the surface area necessary to handle the engine’s impressive torque, while carefully matched clutch springs provide a light feel at the lever.
- Durable five-speed close-ratio transmission.
Chassis/Suspension
- Fourth-generation twin-spar aluminum frame is derived from Honda’s CR(R) series. Forged-aluminum steering head and tapered downtube section are designed to optimize frame rigidity. In addition, tall swingarm pivot plates and thin frame spars create a narrow overall frame cross-section for superb rider comfort and maneuverability.
- Frame design features a single, large-diameter tapered downtube. Two rugged box-section rails attach to the base of the downtube and support the engine. A forged-aluminum steering head provides a compact and extremely durable mount for the frame spars and engine downtube.
- The aluminum frame design is matched to rider ergonomics to maximize handling and control operation.
- Swingarm features a dual-axis, double-taper design with a large cast-aluminum cross-member.
- Front and rear wheels feature HRC works-type lightweight aluminum spoke nipples.
- Front wheel features large-diameter front axle and wide wheel-bearing span for excellent rigidity.
- Rear axle diameter of 25mm and large-diameter bearings provide significant rigidity to withstand torturous track conditions.
- Lightweight 47mm inverted Showa twin-chamber cartridge fork with aluminum dampers. The fork offers 12.4 inches of travel, 16-position rebound and 16-position compression damping adjustability. The inner surface of the front fork outer-tubes receives same honing treatment as works bikes for low-friction operation.
- Pro-Link(R) single-shock rear suspension system features a fully adjustable Showa rear damper and 12.4 inches of wheel travel, separate low-speed (13 positions) and high-speed (3.5 turns) compression damping adjusters and 17-position rebound damping.
- Rear shock damper piston diameter is 50mm for consistent performance under demanding riding conditions.
- Link-type front brake master cylinder provides strong braking while using a light weight brake rotor.
- Compact twin-piston front brake caliper, anodized-aluminum brake pistons and lightweight front brake disc minimize unsprung weight for improved turning and handling.
- HRC works-type rear brake system integrates the rear master-cylinder and fluid reservoir, eliminating the rear master-cylinder reservoir and hose.
- Large 240mm front and rear brake discs.
Additional Features
- All plastic body components (radiator shroud, sidecovers, rear fender, seat base, fuel tank, front fender and front number plate) offer a slim, aggressive style and light weight.
- Frame design allows airbox sidecovers to have larger intake ducts, contributing to significant airflow in the mid- and upper-rpm ranges.
- Rider ergonomics are optimized by adapting the handlebar, seat and footpeg height to place the rider’s legs at the narrowest cross-section of the frame for improved comfort and handling.
- Seat cushion uses foam construction that follows the shape of the fuel tank, providing a smooth transition to increase rider mobility and comfort.
- “Non-slip” seat cover for increased rider control.
- Dunlop 742FA front and 756 rear tires for improved traction and cornering.
- Cleated rear brake pedal and folding shift lever are made of lightweight aluminum and are designed to complement the riding position. Brake pedal features optimized ratio to match integrated rear-brake master-cylinder design.
- Wide, cleated, stainless steel footpegs are self-cleaning, resist corrosion, provide excellent grip and fold for extra ground clearance.
- Aluminum Renthal handlebar (971 bend) is rubber-mounted to reduce rider fatigue and improve comfort.
- Purchase of a new, previously unregistered Honda unit by an individual retail user in the United States qualifies the owner for a one-year complimentary membership in the Honda Rider’s Club of America(TM) (HRCA(R)). Benefits include online access to the Honda Common Service Manual, six issues of the bimonthly Honda Red Rider(TM) magazine, travel discounts, trip routing, MSF reimbursement, plus access to the HRCA Web site (www.hrca.honda.com). Look for the HRCA support team at select off-road events across the country. For details on the HRCA, dealers should call (310) 783-3958, 8:30 a.m. to 5 p.m. Pacific Time.
2007 Honda CRF250R- Specifications |
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Model: |
CRF250R |
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Engine Type: |
249cc liquid-cooled single-cylinder four-stroke |
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Bore and Stroke: |
78mm x 52.2mm |
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Compression Ratio: |
12.9:1 |
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Valve Train: |
Unicam; four-valve |
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Carburetion: |
Keihin 40mm flat-slide with throttle position sensor (TPS) |
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Ignition: |
CD with electronic advance |
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Transmission: |
Close-ratio five-speed |
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Final Drive: |
#520 chain; 13T/51T |
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Suspension: |
Front: 47mm inverted Showa cartridge fork with 16-position rebound and 16-position compression damping adjustability; 12.4 inches travel |
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Brakes: |
Front: Single 240mm disc with twin-piston caliper |
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Tires: |
Front: 80/100-21 |
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Wheelbase: |
58.2 inches |
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Rake (Caster Angle): |
27.50o |
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Trail: |
123mm (4.8 inches) |
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Seat Height: |
38 inches |
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Ground Clearance: |
14.2 inches |
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Dry Weight: |
204 pounds |
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Fuel Capacity: |
2.0 gallons |
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Color: |
Red |
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Consult owner’s manual for optional racing parts. |
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