As expected, BMW introduced the production version of the carbon fiber HP4 RACE at the 2017 Auto Shanghai show. To be produced in a limited run of 750 units, the BMW HP4 RACE claims a fully-fueled weight of just 378 pounds while its S1000RR-based inline-Four claims a maximum output of 212 hp when rated at its crankshaft.
Designed to be a track-focused weapon with no street provisions, the HP4 RACE claims performance similar to a World Superbike racebike, with BMW claiming it even surpasses Superbikes in terms of its suspension and carbon fiber frame. The claimed weight of 378 pounds with a full 4.6-gallon tank is already lighter than BMW’s factory race bikes, as WSBK regulations require a minimum weight of 370 pounds even at the end of a race after using up fuel.
The carbon frame is produced using a Resin Transfer Molding (RTM) process, which BMW claims is a first for motorcycles. The RTM process saturates the carbon with a thermoset resin in a closed mold which BMW says allows for a high level of quality with uniform physical properties. BMW claims the frame weighs just 17.2 pounds, or about 8.8 pounds lighter than the aluminum frame on the S1000RR. The frame is molded as one whole piece with no weak points formed by welds or bolt-on components.
The rear subframe is also made of carbon fiber, though it wasn’t produced using RTM. The subframe is adjustable, changing the seat height from a maximum height of 33.3 inches to a minimum height of 32.1 inches (the HP4 RACE comes preset to a height right in the middle at 32.7 inches).
The engine is based on BMW’s World Superbike and Endurance racing machines, spinning up to 14,500 rpm or 300 rpm higher than the standard S1000RR’s engine. The claimed 212 hp peak is reached at 13,900 rpm while torque tops out at a claimed 88.5 lb.-ft. at 10,000 rpm. BMW engineers altered the camshafts to increase valve lift, while increasing the length of the intake funnels. BMW also reduced the crankshaft’s weight by about 0.4 pound by drilling boreholes into the counterweights and primary drive wheel. Spent gases are fed through a 4-2-1 titanium exhaust system with a carbon fiber muffler.
The six-speed gearbox is optimized for the track, with longer first and second gear ratios and shorter ratios in fourth through sixth compared to the street-legal S1000RR. As a racebike, the HP4 RACE comes standard with a reverse shift pattern with BMW’s HP Shift Assistant Pro allowing for clutchless upshifts and downshifts.
The HP4 RACE also uses carbon fiber wheels, produced in a braiding method wrapping the fibers by machine in one piece. BMW claims the wheels are 30% lighter than conventional wheels with a 40% reduction in gyroscopic forces. BMW also claims the wheels are stronger, testing the theory by running the wheels over a small obstacle at 75 mph. Under this test, light alloy forged wheels broke while the carbon wheels absorbed the energy from the impact.
The front wheel is fitted with Brembo GP4 PR monoblock calipers. Its titanium pistons are treated with a friction-reducing coating for smoother movement through the nickel-plated caliper body. The four-piston rear brake caliper also uses titanium pistons.
Öhlins supplies the fully-adjustable FGR 300 inverted fork, offering 5.1 inches of travel. Steering geometry is adjustable using inserts to offset the fork bridge. The light alloy swingarm is paired to a Superbike-spec Öhlins TTX36 GP strut with 4.7 inches of travel.
BMW also equipped the HP4 with its latest electronics package, including dynamic traction control, wheelie control, launch control, a pit lane speed limiter and a 15-level engine brake function to customize the amount of engine brake torque.
The HP4 RACE is fitted with a 2D multi-function dashboard. When the engine is in gear, the dash displays pertinent information, including electronics settings, lap times and water temperature. When the bike is stopped, the dash switches to mechanic mode for use in the pits or during warm-up. Available when the engine is idling in neutral, mechanic mode shows more detailed information such as front and rear brake pressure, suspension travel, throttle grip position, throttle valve position and lean angle data.
Other features include various carbon fiber trim, a lightweight lithium-ion battery and a BMW HP Motorsport paint scheme. U.S. pricing has yet to be announced but reports out of Europe have the HP4 RACE going for 80,000 euros (approx. US$85,664). Production begins in the fall.
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