BMW Motorrad C 400GT, Руководство пользователя для мотоциклиста

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General instructions
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ing, go to:
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logy
Anti-lock brake system
(ABS)
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, dry asphalt surface.
The lower the coefficient of fric-
tion, the longer the braking dis-
tance.
If the rider increases brake pres-
sure to the extent that brake
force exceeds the maximum
transferable limit, the wheels start
to lock and the Scooter loses
its riding stability. A fall is im-
minent. Before this situation can
occur, ABS intervenes and ad-
apts brake pressure to the max-
imum transferable brake force, so
the wheels continue to turn and
riding stability is maintained irre-
spective 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 reduces braking force to en-
sure that riding stability is main-
tained when the wheels regain
road contact. At this instant the
BMW Motorrad ABS assumes
an extremely low coefficient of
friction (gravel, ice, snow), so
that the wheels will continue to
rotate under all imaginable cir-
cumstances, because this is the
precondition for ensuring riding
stability. As soon as is registers
the actual circumstances, the
system reacts instantly and ad-
justs braking force accordingly to
achieve optimum braking.
Rear wheel lift
Where there is a high level of
adhesion between the tyres
and road, the front wheel is
only blocked very late or not at
all even when the brakes are
applied forcefully. Accordingly,
the ABS control must be applied
very late or not at all. In this
case, the rear wheel can lift off
the ground, which can cause the
Scooter to roll over.
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z Engineering details