First seeing the light of day with the recent introduction of the BMW R1200R (above), the new ASC (Automatic Stability Control) system will be offered as an option on the manufacturer's 2007 versions of the K and R series.
Automobile drivers have for years enjoyed the benefits of electronic traction control and stability control functions, but the unique dynamics of two-wheeled vehicles have prevented similar systems from being adopted on production motorcycles. Until now.
BMW has come up with a new Integral anti-lock braking system that also offers what the German company claims is the "first system in the world serving to control drive spin on production motorcycles." Perhaps they've forgotten about the 1992 Honda ST1100 ABS-TCS that came with an optional traction-control system and remained in the lineup until 2003, but BMW's new system appears to be much more sophisticated.
To be introduced as an optional extra on the touring models in the 2007 model-year K and Boxer series bikes, BMW's ASC Automatic Stability Control prevents the rear wheel from slipping under hard acceleration. The system measures front and rear wheel-speed via the ABS sensors, and when it detects the rear spinning faster than the front, the bike's ECU responds by retarding the ignition to reduce power. If this step alone is not enough to regain traction, the ECU responds by limiting the fuel provided by the electronic injection system.
"This kind of control and management is fast and sensitive," according to BMW, "with any effects on riding comfort and dynamics being virtually negligible."
However well-engineered this system is, BMW notes that ASC can't make a bike corner any faster. "It is essential to note that ASC is not able to push forward, let alone override, the physical limits to the stability of a motorcycle when leaning over in a bend."
Another segment of BMW's ASC is its "lift-off detection and intervention" feature. In plain English, this is an anti-wheelie control that activates when the system detects the front wheel lifting off the ground during maximum acceleration. Those who enjoy the occasional well-timed wheelie will be happy to learn ASC can be switched off, even while riding.
BMW's traction-control system is just the first (or second…) of what we expect will a major field of development among the OEMs. MotoGP has already been exploiting advances in traction- and wheelie-control for several years, and this technology will surely trickle down into most, if not all, high-powered sport machines of the not-too-distant future.
