Bulls 21-17-1093, Translation Of The Original Operating Instructions

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MY21B01 - 22_1.0_02.09.2020
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Overview
3.1.3.3 Back-pedal brake
Figure 12: Brake system with a back-pedal brake –
example
1 Rear wheel rim brake
2 Handlebars with brake lever
3 Front wheel rim brake
4 Pedal
5 Back-pedal brake
The back-pedal brake stops the movement of the
rear wheel when the rider pedals in the opposite
direction to the direction of travel.
3.1.3.4
ABS
Figure 13: BOSCH ABS
1 ABS control unit with housing
2 Display screen
3 ABS indicator lamp
4 Control panel
5 Front wheel brake lever
6 Brake calliper
7 Bike speed sensor
8 Sensor disc
ABS is an added function in some pedelecs.
BOSCH ABS
The rear wheel brake function does not depend on
the
anti-blocking system (ABS) functioning
correctly.
When the brakes are applied, the ABS function
detects critical
slippage thanks to the wheel speed
sensors on the front and rear wheels. The ABS
limits slippage on the front wheel by reducing
brake pressure there, thus stabilising the wheel.
Once the wheel has been stabilised, the wheel is
brought to the blocking limit by building up
pressure selectively.
If the wheel blocks again, the pressure is reduced
again. This process is repeated to keep the wheel
at its limit of traction, thus making optimum use of
the coefficient of friction between the tyres and the
road surface.
The ABS stops when one of the following events
occurs:
• The buffer chamber in the ABS control unit is filled
completely.
• The pedelec is stationary.
• The rider releases the brake.
Besides slippage, the ABS also detects when the
rear wheel is raised during full braking. The ABS
thus counteracts a flip-over during extremely hard
braking manoeuvres.
If the battery is low, the ABS deactivates the motor
assistance first. However, the electric drive sys-
tem, including the display, lighting and ABS, will
remain active until the battery is empty. The elec-
tric drive system the ABS will not switch off until
the battery has almost fully discharged. The brake
system itself remains functional. The ABS is not
active if there is no battery on the pedelec or the
battery is empty.
The indicator lamp lights up for about 5 seconds
before the system switches off completely. The
ABS indicator lamp will go out if the ABS is
unavailable.
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