BMW S 1000R 2015, Rider'S Manual

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can occur, ABS intervenes and
adapts braking pressure to the
maximum transferable braking
force, so the wheels continue
to turn and directional stability
is maintained irrespective of the
condition of the road surface.
What are the effects of
surface irregularities?
Humps and surface irregular-
ities can cause the wheels to
lose contact temporarily with the
road surface; if this happens the
braking force that can be trans-
mitted to the road can drop to
zero. If the brakes are applied
under these circumstances the
ABS has to reduce braking force
to ensure that directional sta-
bility is maintained when the
wheels regain contact with the
road surface. At this instant the
BMW Motorrad Integral ABS
must assume an extremely low
coefficient of friction (gravel, ice,
snow), so that the wheels will
continue to rotate under all ima-
ginable circumstances, because
this is the precondition for ensur-
ing directional stability. As soon
as is registers the actual circum-
stances, the system reacts in-
stantly and adjusts braking force
accordingly to achieve optimum
braking.
What feedback does the
rider receive from the
BMW Motorrad Race
ABS?
If the ABS has to reduce braking
force on account of the circum-
stances described above, vibra-
tion is perceptible through the
handbrake lever.
When the handbrake lever is
pulled, brake pressure is also
built up at the rear wheel by
the integral function. If the
brake pedal is depressed after
the handbrake lever is pulled,
the brake pressure built up
beforehand is perceptible as
counter-pressure sooner than is
the case when the brake pedal is
depressed either before or at the
same time as the brake lever is
pulled.
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 in-
tervene until very late, if at all.
Under these circumstances the
rear wheel can lift off the ground,
and the outcome can be a high-
siding situation in which the mo-
torcycle can flip over.
WARNING
Rear wheel lift due to severe
braking.
Risk of falling
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