BMW R 1250RS, Rider'S Manual

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General instructions
To find out more about engineer-
ing, go to:
bmw-motorrad.com/techno-
logy
Antilock Brake System
(ABS)
Partially integral brakes
Your motorcycle is equipped with
partially integral brakes. Both
front and rear brakes are applied
when you pull the handbrake
lever. The footbrake lever acts
only on the rear brake.
When actively intervening
in the braking process, the
BMW Motorrad Integral ABS
adapts braking-force distribution
between front and rear brakes to
suit the load on the motorcycle,
and so ABS intervention helps
achieve the shortest possible
stopping distance.
ATTENTION
Attempted burn-out despite
Integral braking function
Damage to rear brake and clutch
Do not burn out tyres.
How does ABS work?
The amount of braking force that
can be transferred to the road
depends on factors that include
the coefficient of friction of the
road surface. Loose stones, ice
and snow or a wet road all have
much lower coefficients of friction
than a clean and dry asphalt sur-
face. The lower the coefficient
of friction, the longer the braking
distance.
If the rider increases braking
pressure to the extent that brak-
ing force exceeds the maximum
transferable limit, the wheels start
to lock and the vehicle loses its
directional stability; a fall is im-
minent. Before this situation
can occur, ABS intervenes and
adapts braking pressure to the
maximum transferable braking
force. The wheels continue to
turn and the driving stability is
retained irrespective of the road
condition.
What are the effects of
surface irregularities?
Humps and surface irregularit-
ies can cause the wheels to lose
contact temporarily with the road
surface; if this happens the brak-
ing force that can be transmit-
ted 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 stability is
maintained when the wheels re-
gain contact with the road sur-
face. At this instant the ABS
must assume an extremely low
coefficient of friction, so that the
wheels will continue to rotate un-
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z Engineering details