Vintage_Mania
1979 Honda CB400T
In 1995 Honda re-entered the Paris-Dakar with a bang. The EXP-2 was a radically new and different motorbike, equipped with a revolutionary 400ccm two-stroke engine. After two weeks of racing the african dessert Jean Brucy finished 5th overall and first place in the under-500ccm class.
The EXP-2 was designed to inrease fuel economy, drastically reduce emissions and improve torque characteristics over existing two-strokes. The ARC termed system (Activated Radical Combustion) featured fuel injection and a variable exhaust valve which produced controlled auto-ignition at low to medium throttle settings (at high throttle settings the ignition was controlled by a spark plug). The effect was a thoroughly combustion at low revolutions, whereas in a conventional two-stroke engine unburnt gases would escape into the atmosphere.
A linear and wide powerband was the result, giving the EXP-2 a similar performance to its four-stroke competitors – but a substantially better fuel economy and lower emissions. By increasing the mileage of the bike, it could be raced carrying less fuel, which improved handling and decreased rider fatigue.
Specifications:
Type of engine: Water-cooled 2-stroke single cylinder engine (Activated Radical Control Valve)
AR (Activated Radical Combustion) PGM-FI
Engine displacement: 402 cm³
Maximum power: 54PS / 7000rpm
Dry weight: 155kg
Track record of the EXP-2:
1995: Rally Granada-Dakar: 1st place in the >500ccm class, 5th overall
1995: Baja 1000: 1st place in class 30, 7th overall
1995: Nevada Rally: 1st place in the class A3 (2stroke >251ccm), 8th overall
The EXP-2 was designed to inrease fuel economy, drastically reduce emissions and improve torque characteristics over existing two-strokes. The ARC termed system (Activated Radical Combustion) featured fuel injection and a variable exhaust valve which produced controlled auto-ignition at low to medium throttle settings (at high throttle settings the ignition was controlled by a spark plug). The effect was a thoroughly combustion at low revolutions, whereas in a conventional two-stroke engine unburnt gases would escape into the atmosphere.
A linear and wide powerband was the result, giving the EXP-2 a similar performance to its four-stroke competitors – but a substantially better fuel economy and lower emissions. By increasing the mileage of the bike, it could be raced carrying less fuel, which improved handling and decreased rider fatigue.
Specifications:
Type of engine: Water-cooled 2-stroke single cylinder engine (Activated Radical Control Valve)
AR (Activated Radical Combustion) PGM-FI
Engine displacement: 402 cm³
Maximum power: 54PS / 7000rpm
Dry weight: 155kg
Track record of the EXP-2:
1995: Rally Granada-Dakar: 1st place in the >500ccm class, 5th overall
1995: Baja 1000: 1st place in class 30, 7th overall
1995: Nevada Rally: 1st place in the class A3 (2stroke >251ccm), 8th overall
