BMW R 1250 GS GSA - Rider's Manual > Automatic Stability Control (ASC)

Technology in detail / Automatic Stability Control (ASC)

How does ASC work?

BMW Motorrad ASC compares the wheel speeds of the front and rear wheels. From the speed difference the slip, and with it the stability reserves on the rear wheel are determined. When a slip limit is exceeded, the engine torque is adapted by the engine management system.

What are the design characteristics of the BMW Motorrad ASC?

BMW Motorrad ASC is designed as an assistance system for the rider and for riding on public roads. The extent to which the rider affects ASC control can be considerable (weight shifts when cornering, loose luggage on the motorcycle), especially when approaching the limits imposed by the laws of physics.

The system is not optimized for the special conditions encountered under extreme weather during off-road and race-track use. BMW Motorrad ASC can be switched off under these conditions.

WARNING Risky riding style

Accident hazard despite ASC

  • The rider is always responsible for adapting his/her driving style.
  • Do not reduce the system's extra safety margin with careless riding or unnecessary risks.

Dynamic Traction Control (DTC)

How does Traction Control function?

Traction Control is available in two versions

  • Without taking the angle into account: Automatic Stability Control ASC
  • ASC is a rudimentary function intended to prevent falls.
  • With taking the angle into account: Dynamic Traction Control DTC
  • The additional inclined position and acceleration information enables the DTC to make more precise and comfortable adjustments.

Traction Control compares the wheel circumferential speeds of the front and rear wheels. The slip, and with it the stability reserves at the rear wheel, are determined from the speed difference.

The engine management system adapts the engine torque when the slip limit is exceeded.

WARNING Risky riding style

Risk of accident despite DTC

  • The rider is always responsible for adapting his/her driving style.
  • Do not reduce the system's extra safety margin with careless riding or unnecessary risks.

Special situations

As lean angles increase, acceleration potential is also progressively restricted by the laws of physics. This can result in reduced acceleration when coming out of very tight curves.

To detect spinning or slipping away of the rear wheel, among other things the speeds of the front and rear wheel are compared and the angle with DTC compared to ASC is taken into account.

  • with riding modes Pro OE

If the value for the angle are detected to be implausible for a long period, a replacement value is used for the angle or the DTC function is deactivated. In these cases, a DTC error is displayed.

A self-diagnosis routine must be completed before the error will be displayed.

Under the following unusual riding conditions, BMW Motorrad Traction Control may be deactivated automatically.

Unusual riding conditions:

  • Driving on the rear wheel (wheelie) for a longer period.
  • Rear wheel spinning in place with front brake engaged (burn out).
  • Heating up on an auxiliary stand at idle speed or with gear engaged.

If the coding plug is not in use, turning the ignition off and on again and then riding the motorcycle at a minimum speed reactivates the DTC after a fault.

If the front wheel loses contact with the ground under extreme acceleration, the ASC or DTC function reduces the engine torque in the RAIN and ROAD riding modes until the front wheel makes contact with the ground again.

The riding modes ENDURO and ENDURO PRO are designed for off-road riding and are not suitable for road operation.

In the DTC settings DYNAMIC, DYNAMIC PRO, and ENDURO, the front wheel lift-off detection permits brief wheelies.

In the DTC setting ENDURO PRO, the front wheel lift-off detection is turned off.

In the RAIN, ROAD, DYNAMIC, and ENDURO riding modes, the DTC setting corresponds to the riding mode.

In the ENDURO PRO and DYNAMIC PRO riding modes, the DTC can be set differently.

BMW Motorrad recommends that you respond to the front wheel lifting off by twisting back the throttle grip somewhat to return to a stable driving condition as quickly as possible.

On a slippery surface, the throttle grip should never be suddenly twisted back completely unless the clutch is disengaged at the same time. The engine braking torque can cause the rear wheel to slip, resulting in an unstable driving state. This case cannot be controlled by BMW Motorrad DTC.

Dynamic ESA

- with Dynamic ESA OE

Riding position compensation

The Dynamic ESA electronic chassis and suspension adjustment can automatically adapt your motorcycle to the load. If the spring preload is set to Auto, the driver does not have to worry about adjusting the load.

When the motorcycle is started and while it is being driven, the system monitors the compression of the rear wheel and corrects the spring preload to ensure that the correct driving position is set. The damping is also automatically adjusted to the load.

Using ride height sensors, Dynamic ESA detects the movements of the chassis and suspension and responds to them by adjusting the EDC valves. As a result, the chassis and suspension is adjusted to the conditions of the surface.

Dynamic ESA calibrates itself at regular intervals to ensure that the system is operating correctly.

Adjustment options Damping modes

  • Road: Damping for comfortable road travel
  • Dynamic: Damping for dynamic road travel
  • Enduro: Damping for off-road riding

Load settings

  • Auto: Active riding position compensation with automatic adjustment of spring preload and damping
  • Min: Minimum spring preload
  • Max: Maximum spring preload (for off-road use)
  • The Min and Max spring preloads may be selected by the driver, but they cannot be changed. The riding position compensation function is deactivated in the Min and Max settings.

    See also:

     BMW R 1250 GS GSA - Rider's Manual > General notes

    More information on the topic of technology is available at: Antilock Braking System (ABS) Partially integral brake

     BMW R 1250 GS GSA - Rider's Manual > Riding mode

    Selection In order to adjust the motorcycle to the road condition and the desired riding experience, it is possible to select one of the following riding modes: RAIN ROAD (standard mode)