E1BMW Motorrad Integral ABS
About BMW Motorrad Integral ABS
How does ABS work?
The maximum braking force
it is possible to transfer to the
carriageway depends, among
other things, on the road
surface's coefficient of friction.
Gravel, ice and snow, and
water on the road, have
significantly poorer coeffi-
cients of friction than a dry,
clean asphalt road surface.
The poorer the road's coeffi-
cient of friction, the longer the
braking distance.
If the maximum braking force it
is possible to apply to the road
is exceeded when the rider
increases brake pressure, the
wheels will begin to lock and
directional stability is lost; a fall
threatens. Before this situation
can arise, ABS intervenes and adapts the braking pressure to
the maximum braking force
it is possible to transfer so that
the wheels continue to turn
and driving stability is main-
tained whatever the prevailing
road conditions.
What happens with bumps
in the road?
Corrugated road surfaces or
bumps in the road can cause
the tyres to temporarily lose
contact with the road surface
and hence the braking force it
is possible to apply to drop to
zero. If the brakes are applied
in this situation, the ABS must
reduce the braking pressure to
ensure driving stability when
contact with the road surface
is restored. At this moment,
BMW Motorrad Integral ABS must assume extremely low
coefficients of friction (gravel,
ice, snow) so that the wheels
turn in any conceivable situa-
tion and thus the stability of
the motorcycle is ensured.
Once the actual circum-
stances are detected, the
system will set the brake pres-
sure to the optimum value.
What do we observe during
rider safety training?
Braking in which ABS has to
intervene has, by comparison
with normal braking, a signifi-
cantly higher demand for
electricity which puts a heavy
load on the battery. The
battery is constantly being
charged in normal riding so
that it always has sufficient
capacity available. Info_I_ABS_en_xx.fm Seite 1 Dienstag, 19. Juli 2005 2:48 14
E3BMW Motorrad Integral ABS
To achieve the shortest
braking distance, it is neces-
sary to apply the front brake
gradually and with increasing
force. This makes best use of
the dynamic increase in load
on the front wheel. At the
same time, the clutch should
be disengaged.
In emergency braking as it is
often taught, in which the
brake pressure is generated
as quickly as possible and with
all possible force, the dynamic
load distribution cannot follow
the increasing deceleration
and the braking force cannot
be completely transferred to
the road. The ABS has to
intervene to ensure that the
front wheel does not lock up;
this reduces the brake pres-
sure and the braking distance
is extended.What happens if ABS control
fails?
A fault in BMW Motorrad
Integral ABS is indicated by a
corresponding warning dis-
play in the instrument cluster.
If only ABS control fails, the
Integral system and the brake
servo action remain opera-
tional. If these systems also
fail, the residual brake function
is applied. In this case, the
forces to be applied to the
brake levers will be signifi-
cantly higher and the lever
travel required will be longer.
The residual brake function is
a mechanical function and is
always available in the event
of the failure of the BMW
Motorrad Integral ABS,
whatever the battery condi-
tion. It meets all requirements
of legislation around the world on the design of brakes for
motor vehicles and allows the
rider to brake the motorcycle.
The following notes must be
observed for riding with the
residual braking function:
• set the brake lever to
maximum travel
• always brake with both front
and rear brakes
• where it is safe to do so, try
out the brakes so that you
can learn the brakes'
response characteristics
• be aware of the prevailing
road conditions and adapt
your braking force
accordingly
• since this is an emergency-
run function, you should visit
a specialist workshop, or
better still a BMW Motorrad
dealer, as quickly as
possibleInfo_I_ABS_en_xx.fm Seite 3 Dienstag, 19. Juli 2005 2:48 14
