BMW R 1200 ST Rider's Manual page 85

plied as rapidly as possible
and with the rider's full force
applied to the brake levers;
under these circumstances
the dynamic shift in load dis-
tribution cannot keep pace
with the increase in decel-
eration and the tyres cannot
transmit the full braking force
to the surface of the road.
ABS has to intervene to keep
the front wheel from locking;
this increases stopping dis-
tance.
Rear wheel lift
Even under severe braking,
a high level of tyre grip can
mean that the front wheel
does not lock up until very
late, if at all. Consequently,
ABS does not intervene until
very late, if at all. Under these
circumstances the rear wheel
can lift off the ground, and the
outcome can be a highsiding
situation in which the motor-
cycle can flip over.
Severe braking can
cause the rear wheel to
lift off the ground.
When you brake, bear in mind
that ABS control cannot be
relied on in all circumstances
to prevent the rear wheel from
lifting clear of the ground.
What is the design
baseline for BMW
Motorrad Integral ABS?
Within the limits imposed by
physics, the BMW Motorrad
Integral ABS ensures direc-
tional stability on any surface.
The system is not optimised
for special requirements that
apply under extreme compet-
itive situations off-road or on
the track.
Special situations
The speeds of the front and
rear wheels are compared
as one means of detecting a
wheel's incipient tendency to
lock. If the system registers
implausible values for a
lengthy period the ABS
function is deactivated
for safety reasons and
an ABS fault message is
issued. Self-diagnosis has
to complete before fault
messages can be issued.
In addition to problems with
the BMW Motorrad Integ-
ral ABS, exceptional riding
conditions can lead to a fault
message being issued.
Exceptional riding
conditions:
Heating up with the motor-
cycle on the centre stand
or an auxiliary stand, en-
gine idling or with a gear
engaged.
5
83
z