BMW F 800 GS Adventure Rider's Manual page 80

How does ASC work?
7
The BMW Motorrad ASC com-
pares the wheel speeds of the
78
front and rear wheels. Differ-
ences in the relative rotation
speeds allow the system to de-
termine the slip rate, and thus
the stability reserves at the rear
wheel. The engine-management
system adapts the engine torque
when the slip limit is exceeded.
What are the design
characteristics of the
BMW Motorrad ASC?
BMW Motorrad ASC has been
designed to provide the rider with
z
extra assistance during motor-
cycle operation on public roads.
The extent to which the rider af-
fects ASC control can be con-
siderable (weight shifts when
cornering, loose luggage on the
motorcycle), especially when ap-
proaching the limits imposed by
the laws of physics.
The ENDURO riding mode
should be activated for off-
road riding. In this mode ASC's
closed-loop intervention is
delayed to allow controlled drifts.
The system is not optimized for
the special conditions encoun-
tered under extreme weather
during off-road and racing use.
BMW Motorrad ASC can be
switched off for these conditions.
Even with ASC, the laws of
physics cannot be overrid-
den. The rider is always respon-
sible for adapting his/her driving
style.
Do not reduce the additional
safety provided with risky
driving.
Special situations
As lean angles increase, accel-
eration potential is also progres-
sively restricted by the laws of
physics. This can result in de-
layed acceleration when coming
out of very tight curves.
The system compares the rota-
tion speeds of the front and rear
wheels to detect any tendency
of the rear wheel to spin or break
loose. If the system registers im-
plausible data for an extended
period of time it will deactivate
the ASC functionality as safety
precaution and a display will alert
you to ASC error. A self-diagno-
sis routine must be completed
before the error will be displayed.
The following unusual operating
conditions may lead to automatic
deactivation of BMW Motorrad
ASC:
Riding on the rear wheel only
(wheelie).
Rear wheel spinning in place
with front brake engaged (burn
out).