13th August 2012
BMW Motorrad has launched the BMW HP4, the lightest 4-cylinder supersports bike in the 1000cc class to date. Based on the BMW S 1000 RR, the new sports motorcycle has an output of 142 kW (193 hp) and weighs just 199 kg (438 lbs) including Race ABS and a 90% full fuel tank (169 kg dry weight with Race ABS).
The issue of weight is normally associated with cars and planes but of course the same principles apply to other products. A lighter structure can help to improved fuel economy and allows the bike to accelerate faster with improved handling characteristics.
New finely wrought 7-spoke wheels in forged light alloy and a new, lighter sprocket carrier give the HP4 a weight reduction of 2.4 kg as compared to the RR.
The exhaust system is made entirely of titanium and saves as much as 4.5 kilograms compared to the RR, thereby contributing to the HP4′s enhanced handling qualities. The new exhaust system has an interference pipe between cylinders two and three, a controlled acoustic valve and a closed-loop catalytic converter. It has been possible to optimise the torque curve thanks to the new exhaust system, with the engine application adapted accordingly.
Launch control and Brembo Monobloc brakes with ABS keep the bike from getting away, while liquid cooling keeps the 193 horsepower engine from overheating as it accelerates from zero to 100 kmh in 2.9 seconds.