Honda 2002 CRF450R


CRF450R
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2002 HONDA CRF450R Four-Stroke
Model Features

Honda unleashes long-awaited 4-stroke motocrosser
Specifications | Model Overview/Photos

The 2002 CRF450R is Honda's first four-stroke motocrosser ever, and is claimed to posses the best power-to-weight ratio available. The CRF is loaded with CR-inspired racing technology, including a new powerful Unicam engine and Honda's latest lightweight twin-spar aluminum frame.

Features & Benefits

Unique Features

Powerful new engine is claimed to churn out 55 bhp at 9000 rpm with 36 lb./ft. of torque at 7000 rpm. Power is produced across a wide rpm for maximum rideability.

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.

Auto decompression and hot restart system to make starting easier in all conditions.

Twin-spar aluminum frame and swingarm utilize Honda's CR aluminum frame design expertise to ensure compliance, rigidity and strength while providing a narrow cross section for excellent rider comfort and maneuverability.

Weight-saving measures include the use of exotic materials such as the titanium intake valves and exhaust header.

Class-leading 225-pound dry weight contributes to incredible acceleration and handling performance.

Engine/Drivetrain

Liquid-cooled four-valve SOHC 449cc engine produces more than 120 hp per liter while maintaining Honda's legendary dependability.

Compact, lightweight engine assembly weighs only 65.4 pounds.

Unicam valve train features a carburized single camshaft that directly actuates two 36mm titanium intake valves. The camshaft exhaust lobe actuates two 31mm steel exhaust valves via a forked, low-friction, roller rocker arm. A separate cam holder contributes to the compact design, which allows a remarkable 21.5-degree included valve angle and saves 13.3 ounces over a comparable DOHC system.

Lightweight titanium intake valves permit use of smaller valve springs, reducing overall engine height and saving 15.2 grams per valve compared to a steel valve design.

Unique, pin-rotation-type auto decompressor produces a lightweight, compact system that provides superb cold-starting and hot-restarting.

Crankshaft is made of high-strength, low-carbon steel with carburized main journals for maximum durability at sustained high-rpm.

F-1-type forged, 11.5:1 compression mini-skirt piston is 112 grams 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 and quieter operation for extended engine life.

Press-fitted spark plug pipe fits between forked exhaust rocker arms, further contributing to compact cylinder head design.

40mm FCR-type carburetor features four rollers on the flat slide, resulting in very light throttle effort, smooth operation, crisp throttle response and excellent rideability.

An 8-bit digital CPU incorporates the Capacitive Discharge Ignition (CDI), producing immediate data calculation and extremely accurate ignition for maximum performance.

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, and reduces the amount of circulating oil and the required size of the oil pump.

Vertically split crankcases feature a built-in oil pump, reducing weight 5.1 ounces compared to a conventional design.

Exhaust system uses a lightweight titanium exhaust header and repackable aluminum muffler with stainless steel pipe.

Dual radiators provide significantly more surface area and more effective heat dissipation compared to a single-radiator design.

Gear-driven balancer reduces vibration and drives the water pump. Eight clutch plates provide the surface area necessary to handle the engine's massive torque, while carefully matched clutch springs provide a light feel at the lever.

Durable five-speed close-ratio transmission matches the engine's power delivery.

Primary kick starting system allows starting in any gear.

Chassis/Suspension

Twin-spar aluminum frame is a third-generation design derived from Honda's CR series. Tall swingarm pivot plates and thin frame spars create a narrow overall frame cross-section for superb rider comfort and maneuverability.

Semi-double-cradle 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.

CR-type swingarm features a dual-axis, double-taper design with a large cast aluminum cross-member.

CR-spec front and rear wheels feature HRC works-type, lightweight aluminum spoke nipples. Compared to a conventional design, front wheel unsprung weight is reduced by 3.5 ounces. Together with a revised rear wheel, hub and spoke design, rear wheel unsprung weight is reduced 15.9 ounces.

Front wheel features large-diameter front axle and wide wheel-bearing span for excellent rigidity.

Optional 20-inch front wheel improves cornering traction and rider comfort.

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 is derived from the CR250R and features settings unique to the CRF. Featuring 12.0 inches of travel, 16-position rebound and 16-position compression damping adjustability, the inner surface of front fork outer-tubes and rear damper case are molybdenum-coated for smooth, low friction operation.

CR-type Pro-Link 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's damper piston diameter is 50mm for consistent performance under demanding riding conditions.

Compact dual-piston front brake caliper, anodized aluminum brake pistons and lightweight front brake disc minimize unsprung weight for improved turning and handling.

New HRC works-type rear brake system integrates the rear master cylinder and fluid reservoir, eliminating the rear master cylinder reservoir and hose. Together with a smaller caliper and smaller-diameter rear brake piston, overall system weight is reduced by 11.8 ounces compared to a conventional design and serviceability is improved.

Large, 240mm front and rear brake discs.

Additional Features

Design allows side covers to have larger air-intake ducts, contributing to significant airflow in the mid- and upper-rpm range.

Rider ergonomics are optimized by adapting the handlebar, the seat and the footpeg height to place the rider's legs at the narrowest cross-section of the frame, for improved comfort and handling feel.

Seat cushion uses multi-density foam construction that follows the shape of the fuel tank, providing a smooth transition to increase rider mobility and comfort.

Brake pedal and shift lever 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.

Cleated rear brake pedal and shift lever are made of lightweight aluminum.

Adjustable front brake lever.

Handlebar is rubber-mounted to reduce rider fatigue and improve comfort.

CR handlebar holders provide three different mounting positions: standard CRF450R holder provides neutral position and optional holder (CR125R-type) provides +/-3mm fore or aft position to match rider preference.

Works-type handlebar grips add to rider comfort.

New chain guide material offers improved wear resistance and service life is three times greater than conventional materials. Chain roller features a tough, double-sealed bearing.

Front disc brake cover helps protect rotor and caliper from damage.

Removable rear subframe allows easy maintenance.

Washable, two-stage foam air filter for optimal engine protection and easy maintenance.

Repackable silencer for maximum performance and minimal noise.

Comfortable, durable controls and high-quality fasteners.

Stainless steel clutch cable for long life.

Specifications

Model: CRF450R
Engine Type: 449cc liquid-cooled single-cylinder four-stroke
Bore and Stroke: 96mm x 62.1mm
Compression Ratio: 11.5:1
Valve Train: SOHC; four-valve
Carburetion: Keihin 40mm flat slide
Ignition: Solid-state CD with electronic advance
Transmission: Close-ratio five-speed
Final Drive: #520 chain; 13T/50T
Suspension
Front: 47mm inverted Showa cartridge fork with 16-position rebound and 16-position compression damping adjustability; 12.0 inches travel
Rear: Pro-Link Showa single shock with spring preload, 17-position rebound damping adjustability, and compression damping adjustment separated into low-speed (13 positions) and high-speed (3.5 turns); 12.4 inches wheel travel
Brakes
Front: Single 240mm disc with twin-piston caliper
Rear: Single 240mm disc
Tires
Front: 80/100-21
Rear: 110/90-19
Wheelbase: 59.4 inches
Rake (Caster Angle): 28.6°
Trail: 119mm (4.68 inches)
Seat Height: 37.2 inches
Ground Clearance: 13.0 inches
Dry Weight: 225.0 pounds
Fuel Capacity: 2.0 gallons

Color(s): Red
Available: October 2001
Suggested Retail Price: $6,299 (US)

Model Overview CRF450R

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