The HP4 screams racebike when equipped with BMW's competition package, as shown here.
The HP4's dash has new options to accommodate the bike's added levels of adjustment. Notice here the bike's TC is set to -7, which is one of just 15 options.
A new rocker switch on the left clip-on allows on-the-fly TC adjustment when the bike is in Slick mode.
The HP4 comes standard with a lightweight, all-titanium exhaust. When equipped with BMW's Competition Package it also comes with adjustable rearsets, blue metallic wheels, a longer carbon fiber belly pan, hinged brake and clutch levers and a sponsor sticker kit.
In addition to revised ABS parameters, the HP4 comes equipped with special brake pads and Pirelli Supercorsa SP tires.
The right leg of the HP4 fork is equipped with a spring but no damping valve, whereas the left leg has a damping valve but no preload adjustment.
The electromagnetic valve in the shock is the same as used in the fork. It's also the same valve used in every M series car BMW builds.
The HP4 feels lighter on its toes thanks to the forged aluminum wheels, and also more active mid-corner as a result of the constant DDC adjustments.
BMW has dominated nearly every literbike shootout it’s contended since the introduction of the brutally quick S 1000 RR back in 2009. No amount of victories or praise seems to be sufficient for the Bavarian manufacturer however, as evidenced by the company’s recent release of the HP4, a more sophisticated version of its S 1000 RR. With the bike’s showroom debut now in sight, we headed to the Circuito de Jerez in Jerez, Spain, to see exactly how far BMW has raised the bar for 2013.
The HP4 is the fourth High Performance (HP) model to be offered by BMW but the first to use a four-cylinder platform. In terms of improvements when compared to the RR, the bike boasts BMW’s Dynamic Damping Control, IDM-developed Race ABS, launch control, a more customizable traction control system and improved wheelie control intervention levels. The refinements don’t end at the HP4’s ECU however; the bike also benefits from a titanium exhaust system, a lighter battery and forged aluminum wheels sporting Pirelli’s sticky Supercorsa SP tires. The result of BMW’s all-in tactic is a claimed curb weight of 438 pounds. Compare that to the lightest four cylinder contender in our 2012 literbike comparison, the Kawasaki ZX-10R, which weighed in at 442 pounds with a full tank of fuel.
The HP4 makes use of an untouched S 1000 RR engine and thus isn’t hurting in the power department. All 193 horsepower (measured at the crankshaft) are tuned to stretch your limbs, plus there’s an added punch between 6000 rpm and 9750 rpm for enhanced midrange excitement. What’s more, the HP4 isn’t restricted in any of its four riding modes, meaning you have access to every last horsepower in Rain, Sport, Race and Slick mode. For improved control on wet or slippery surfaces, BMW has altered the torque and power curve of Rain mode between 2500 rpm and 8000 rpm for a smoother buildup of power.
More impressive than the HP4’s over-the-top power figures is its Dynamic Damping Control (DDC), which pulls data from various sensors to provide semi-active suspension adjustment in real-time. The system itself is a first for production sportbikes, although not new technology for BMW, who’s been using nearly identical equipment on its M series vehicles for years now. When compared to Ducati’s electronic suspension, the HP4’s setup is different in that it provides damping adjustment on-the-fly, without rider input.
The HP4’s DDC system operates off a designated ECU that analyzes such parameters as lean angle, lean angle rate of change, acceleration, speed and spring travel. Upon crunching these various numbers, the DDC manipulates suspension rates at an astounding rate by either closing or opening internal damping orifices via an electromagnetic valve. Transition aggressively through a chicane, for instance, and the damping rate will go from soft to hard (for stability at the peak of your transition) then back to soft again as you tip the bike on its opposite side. Similarly, as you increase lean angle through a corner, the front suspension will soften up for better compliance and to not overwork the carcass of the front tire.
All 193 horsepower (measured at the crank) are tuned to stretch your limbs, plus there’s an added punch between 6000 rpm and 9750 rpm for enhanced midrange excitement
BMW electronics don’t control every aspect of damping, so don’t throw away your knowledge for dialing in a bike’s suspension just yet. Changes to the damping rates are now accomplished by means of a new-for-2013 menu option rather than with a screwdriver, and riders can alter the base setting via 15 levels of adjustment. Front and rear changes vary in the fact that changes to the front are made as one rate, whereas changes to the rear are made both on the compression and rebound side. At its baseline, Rain and Sport mode focus on around-town comfort, whereas Race and Slick are centered on aggressive track riding.
The HP4’s DTC system offers a similar level of fine-tuning, although the 15 added levels of adjustment can only be accessed in Slick mode. Toggling to 0 provides the same level of intervention as that of Slick mode on the standard RR, while anything beyond this increases TC intervention. Steps 0 to -7, in contrast, allow the HP4 to spin akin to a Gary McCoy-ridden racebike with liberal use of the throttle.
The S 1000 RR is famous for its ability to send chills down your arms and blood rushing to your eyeballs at the mere thought of a cracked throttle. But as enticing as that in-your-face performance is, the standard RR’s brute power and obtrusive electronics can quickly become overwhelming. The HP4, by comparison, feels much more refined, much easier to ride, and much more forgiving when ridden aggressively.
Rolling through the tight, right-hand turn two at Jerez demonstrates how much more user-friendly the HP4 is than the standard RR. Rolling the throttle on mid-corner isn’t met by an aggressive lash in the driveline but rather a smooth, controllable burst of acceleration that allows you to increase corner speed without hair-raising excitement. The bike feels lighter than the RR as you transition into the left-hand turn three and doesn’t have the tendency to snap the front wheel toward the sky as you drive forward; it still doesn’t feel like the lightest steering literbike, but the electronics do feel much more refined and better suited toward driving forward. As a whole, it feels like you fight the HP4 less than you fight the S 1000 RR.
...the bike always feels well damped for the portion of track you’re covering, be it a braking zone, corner entry, or transition
The HP4 feels lighter on its toes than the RR through faster corners thanks in part to the forged aluminum wheels, and also more active as a result of its Dynamic Damping Control. The DDC adjustments don’t feel heavily layered, however, and an insensitive butt could literally go without ever feeling the bike “adapt” mid-corner since changes to the damping are (potentially) made every 10 milliseconds. One thing you will notice is that the bike always feels well damped for the portion of track you’re covering, be it a braking zone, corner entry, or transition. The area that benefits most, in my opinion, is the corner exit, where the shock gets stiffer to prevent chassis pitch under hard acceleration.
The reworked traction control settings and new wheelie control programming finally feel up to the task of helping rather than hindering your drive. For comparison, I turned the RR’s electronics off while running my fast laps during our 2012 literbike comparison, but I never once had to consider relying on “me-only” control while lapping the HP4.
The bike feels better than the RR in every other sense; the new exhaust system sounds to have more grunt but isn’t obnoxiously loud at full song, the Supercorsa SP tires have better feel at full lean, and the newly developed Race ABS doesn’t intrude at extreme levels of braking. What’s more, the bike looks and feels like a racebike when equipped with BMW’s Competition Package, which adds adjustable rearsets, hinged brake and clutch levers, a sponsor sticker kit and carbon fiber belly pan.
Even without the Competition Package, the HP4 feels like a racebike. It’s composed, powerful and, most importantly, easy to go quick on. That’s not to say that the RR isn’t an already capable machine, but at the end of the day the HP4’s electronics and handling characteristics are simply better. Needless to say, BMW has raised the bar even higher this time around.
For an even closer look at what sets the HP4 apart for the standard S 1000 RR, and for a more detailed on-track review, be sure to grab the December issue of Sport Rider Magazine, which goes on sale October 23, 2012.