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240 Landmarks TopMotorcycles > Yamaha YZ400F
 Yamaha YZ400F
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The first model that overturned the idea that a 2-stroke engine is best suited for a motocross bike. In contrast to lightweight and high power 2-stroke engines, the 4-stroke engine of the YX400F had a wide power band, and starts linearly from very low speeds in response to the opening of throttle. These characteristics prevented unnecessary wheel spins and dramatically improved rear traction. This ease of handling reduced rider fatigue and allowed the rider to exploit the potential of the bike even in motocross races lasting more than 30 minutes. Due to the greater efficiency and power of the 4-stroke engine, a YZ400F was ridden to the overall championship in its first AMA season. In an instant it became popular throughout the market, and now 4-stroke motocross bikes have become the mainstream.
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Storage location:YAMAHA COMMUNICATION PLAZA
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Year manufactured:1997
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Manufacturer:Yamaha Motor Co., Ltd.
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Classification:Mass-production vehicle
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Current status:On display (static): operational
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Vehicle name / Manufacture
Vehicle name:YZ400F
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Model:5BE1
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Company name:Yamaha Motor Co., Ltd.
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Vehicle type/usage:Motorcycle for off-road competitions
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Location of actual vehicle/replica:Communication Plaza
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Year manufactured:1997
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Model / Weight
Style:Motocross bike
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Passenger capacity:1
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Weight:107 kg (dry)
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Body / Size
Overall length:2176 mm
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Overall width:827 mm
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Overall height:1303 mm
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Headlamp type:None
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Tire size (front):80/100-21
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Tire size (rear):110/90-19
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Body / Axle / Driving / Others
Frame:Steel pipe semi-double cradle
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Suspension type (front):Telescopic
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Suspension type (rear):Swing arm (Mono cross)
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Wheelbase:1496 mm
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Vehicle height adjustment:
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Steering:Bar handle
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Brakes (front):Hydraulic single disc
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Brakes (rear):Hydraulic single disc
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Damper (front):Oil damper
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Damper (rear):Gas charged oil damper
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Engine/ Size / Power
Type:Water-cooled 4-stroke DOHC 5-valve
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Cylinder arrangement:Single cylinder
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Valve train:DOHC 5-valve
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Carburetor:FCR39×1
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Bore x stroke:92.0×60.1 mm
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Displacement:399 cm³
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Ignition system:CDI
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Max. power/r.p.m.:40.4 kW (55.0 ps)/9000 rpm
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Max. torque/r.p.m.:45.7 kW (4.67 kgf・m)/7000 rpm
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Lubrication method:Dry sump
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Start method:Kick
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Fuel tank capacity:8.0 L
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Drive-train
Transmission:Continuously variable transmission 5 forward speeds
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Power transmission method:Gear (1st), chain (2nd)
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Clutch type:Wet multiple disc
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Performance
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Features:The first commercial motocross bike with a 4-stroke engine with the power to win races.
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