BMW Motorrad C 400GT, Руководство пользователя для мотоциклиста

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Safety reserves
BMW Motorrad ABS may not
mislead the rider into a careless
riding style because they can rely
on shorter stopping distances.
It is primarily there to provide
a safety reserve for emergency
situations.
Take care in bends! Braking in
bends is subject to particular
laws relating to the physics of
riding which even BMW Motorrad
ABS cannot evade.
Automatic Stability
Control (ASC)
How does ASC work?
BMW Motorrad ASC compares
the wheel speeds at the front
and rear wheel. The differential is
used to compute slip as a meas-
ure of the reserves of stability
available at the rear wheel. If slip
exceeds a certain limit, the en-
gine management system inter-
venes and adapts engine torque
accordingly.
Special situations
In accordance with the laws of
physics, the ability to accelerate
is restricted more and more as
the angle of heel increases. Con-
sequently, there can be a per-
ceptible reduction in acceleration
out of very tight bends.
The speeds of the front and
rear wheels are compared as
one means of detecting the rear
wheel's incipient tendency to
spin or slip sideways. If the sys-
tem registers implausible values
for a lengthy period the ASC
function is deactivated for safety
reasons and an ASC fault mes-
sage is issued. Self-diagnosis
has to complete before fault
messages can be issued.
If the front wheel lifts clear of the
ground under severe accelera-
tion, the ASC reduces engine
torque until the front wheel re-
gains contact with the ground.
Under these circumstances,
BMW Motorrad recommends
rolling the throttle slightly closed
so as to restore stability with the
least possible delay.
Never turn the throttle grip all
the way back suddenly when on
slippery road surfaces. Engine
braking torque can cause the
rear wheel to lock, with a cor-
responding loss of stability. The
BMW Motorrad ASC is unable to
control a situation of this nature.
Slippery roadway
On very loose surfaces (e.g. sand
or snow) ASC control interven-
tions may reduce the driving
power at the rear wheel to an
extent where the rear wheel no
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z Engineering details