2004 Yamaha YZ450F Competition Model

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2004 Yamaha YZ450F Competition Model

Post by 4Strokes » Thu Oct 26, 2017 8:20 am

2004 Yamaha YZ450F Competition Model
Keeping our ears to the dirt has been critically important over the years, and we've been picking up some seriously strong vibrations ever since we built the world's first modern four-stroke motocrosser. Making improvements is how we continue to evolve a tighter, quicker, easier-to-deploy package. The YZ450F's high-revving counterbalanced 449cc liquid-cooled five-titanium valved 39mm Keihin-carbureted single is pure moto winning magic.

Upgrades for 2004 consist of a rigid 48mm fork with new settings for a smooth, compliant and progressive feel. New, titanium foot pegs and gripper-style seat cover material improve the crucial interface between man and machine -- and man, what a machine: 222 pounds of high-tensile steel-framed, loam-launching, terrain-following, thrill-seeking motocross machine.

Yamaha-exclusive five titanium valve head (three intake, two exhaust) reduces reciprocating mass and helps make 11,000 rpm a regularly recurring event. Bringing a 95mm piston to life against 12.5:1 compression can be hard work; YZ450F's genius auto-decompression system and hot start lever make it quite easy. And four speeds are plenty, given the YZ450F's seismic spread of power -- and a heavy-duty clutch that gets the power to the ground consistently. It's fast, it's furious, and it's Motocross Action magazine's 2003 Bike of the Year. Suggested Retail: $6,299 USD.

Engine Specifications
Type: 449cc, 5-valve (titanium) liquid-cooled, DOHC, four-stroke
Bore & Stroke: 95 x 63.4mm
Compression ratio: 12.5:1
Ignition: Digital CDI
Carburetor: 39mm Keihin FCR flat-slide w/throttle position sensor
Carb Jetting: #165 Main / #100 Pilot Air / #42 Pilot Jet

Transmission Specifications
Type: 4-speed, multi-disc wet clutch
Gearing: 62 / 22 (2.818)

Chassis Specifications
Frame: Semi-double cradle
Front suspension: 48mm Kayaba inverted telescopic fork, 11.8" travel; adj. compression & rebound
Rear suspension: Fully adjustable Kayaba shock, 12.4" travel; separate Hi/Lo compression adjustments
Rake / Trail: 27.2° / 4.7"
Front brake: 250mm floating disc
Rear brake: 245mm disc
Front tire size: 80/100-21 Dunlop 739
Rear tire size: 100/90-19 Dunlop 739

Fuel tank: 1.8 gallons

Dimension and Dry Mass
Overall length: 85.5"
Overall width: 32.6"
Overall height: 51.3"
Wheelbase: 58.5"
Ground clearance: 14.6"
Seat height: 39.2"
Dry mass: 222 lbs.

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New for the 2004 Yamaha YZ450F

Post by 4Strokes » Mon Dec 04, 2017 1:39 pm

  • A bigger, 48mm fork with revised internals for a smooth, compliant feeling throughout the stroke, while a special new coating reduces stiction.
  • New anodized triple clamps accommodates the larger forks and give that factory look while carrying the handlebar aggressively low and forward.
  • Brake calipers now contain light, aluminum pistons.
  • New, titanium foot pegs increase strength, reduce weight, and provide more grip.
  • New gripper-style seat cover material.

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