Aprilia RS 250

The RS250 is that increasingly rare item: a current two-stroke production roadbike. Emissions legislation worldwide has made the large-capacity two-stroke engine a thing of the past, with its poor fuel consumption and excessively dirty exhaust emissions. But Aprilia's RS250 continues to provide some of the purest motorcycling performance available. The heart of the bike is a rather outdated engine, Suzuki's RGV250 motor, first seen in 1989. It's a V-twin two-stroke, with several advanced power-boosting features, including guillotine-type power valves, electronically-controlled 34mm Mikuni flat-slide carburettors and ceramic-coated cylinders.

Aprilia modified the RGV's exhaust and intake systems to produce a power increase to 52kW (70bhp) at the crankshaft, equivalent to 280bhp/litre: the highest specific power output of any current production roadgoing motorcycle.

The rest of the bike is more than capable of handling this impressive power figure. A twin-spar aluminium frame provides super-stiff handling, and the fully-adjustable Showa upside-down front forks and rear monoshock allow a wide range of adjustment for any track or road situation. Wide sports tyres provide amazing grip, and the front twin Brembo four-piston calipers offer superlative stopping power, especially for a bike weighing just 140kg (2241b).

While the RS250's engine is based around a design that's more than a decade old, the styling is undoubtedly modern. A banana-style upswept aluminium swingarm and twin side-mounted exhausts pay tribute to the Grand Prix technology behind the RS, as well as providing a unique look. Since Suzuki discontinued its RGV250, the RS250 has been unique in its class. The closest rivals to this mini-racebike are the four-cylinder 400cc four stroke machines like Honda's VFR400 and Kawasaki's ZXR400. But these heavier machines can't provide the ultimate cornering experience of the RS250, nor the exhilaration of the 250's screaming two stroke acceleration.