BMW R1200RT Rider's Manual page 109

The footbrake lever acts only on
the rear brake.
BMW Motorrad Integral ABS
adapts the brake force distribu-
tion between the front and rear
brakes during braking by means
of ABS modulation to suit the
load carried by the motorcycle.
Spinning of the rear wheel
with the front brake applied
(Burn Out) is prevented by the
integral function. The result may
be damage to the rear wheel
brake and the clutch.
Do not attempt Burn Outs.
How does the Integral
ABS work?
The maximum braking force that
can be transferred to the road
surface is partially dependent on
the friction coefficient of the road
surface. Gravel, ice, snow and
wet roads offer a considerably
lower friction coefficient than a
dry, clean asphalt surface. The
poorer the friction coefficient of
the road surface is, the longer
the braking distance will be.
If the maximum transferable brak-
ing force is exceeded when the
rider increases the brake pres-
sure, the wheels begin to lock
and driving stability is lost, and
a fall can result. Before this sit-
uation occurs, ABS is activated
and the brake pressure is ad-
justed to the maximum transfer-
able braking force. This enables
the wheels to continue to turn
and maintains driving stability re-
gardless of the road surface con-
dition.
What happens when
rough roads are
encountered?
Bumpy or rough roads can briefly
lead to a loss of contact be-
tween the tires and the road sur-
face, until the transferable brak-
ing force is reduced to zero. If
braking is carried out in this sit-
uation, ABS must reduce the
brake pressure to ensure driv-
ing stability when restoring con-
tact to the road. At this point in
time, the BMW Motorrad Integral
ABS must assume extremely low
friction coefficients (gravel, ice,
snow) so that the running wheels
turn in every imaginable case and
the driving stability is ensured.
After detecting the actual con-
ditions, the system adjusts the
optimum brake pressure.
In what ways is the
Integral ABS noticeable
to the rider?
If the ABS system has to reduce
the braking force due to the con-
ditions described above, then
vibrations can be felt through the
handlebar brake lever.
If the handbrake lever is pulled,
then braking pressure is built up
at the rear wheel with the integral
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