Honda EXP-2

The Honda EXP-2 was an off-road experimental prototype motorcycle, designed in 1995, with a fuel-injected 400 cc two-stroke engine. It was intended to serve global markets that still relied heavily on two-stroke technology while complying with increasingly strict emissions laws. With a redesigned exhaust port valve and the ARC, Activated Radical Combustion, system engaged, the engine would produce a pre-ignited combustion effect at low throttle that completely burned all the fuel in the chamber, in contrast to a conventional two-stroke, which loses part of the intake charge. The result reduced two major drawbacks of two-stroke technology: incomplete combustion of fuel at low engine revolutions and the expulsion of unburned fuel at high revolutions. The EXP-2 ran in the 1997 Granada-Dakar rally.