English – 2
The numbering of the components shown refers to the illus-
trations on the graphics pages at the beginning of the
manual.
(1) Drive unit
a)
(2) Speed sensor
(3) Spoke magnet
b)
(4) CenterLock magnet
(5) Rim magnet
a) different sensor type and installation position is possible
b) different installation position is possible
Technical data
Drive unit
Product code
Continuous rated power
Torque at drive, max.
Rated voltage
Operating temperature
Storage temperature
Protection rating
Weight, approx.
The Bosch eBike systems use FreeRTOS (see www.freertos.org).
A)
Bicycle lights
Voltage approx.
Maximum power
A) Depends on legal regulations, not possible in all country-specific
models via the eBike battery
Inserting a bulb incorrectly can cause it to blow.
Information on the noise emissions of the drive
unit
Typically, the A-weighted noise emission level of the drive
unit is < 70 dB(A). A key feature of the <eBike Alarm> ser-
vice is that the drive unit will emit an alarm tone in response
to unauthorised movement of the eBike. This alarm tone can
exceed a noise emission level of 70 dB(A) and measures
80 dB(A) at a 2 m distance from the drive unit. The alarm
tone is only available once the <eBike Alarm> service has
been activated and can be deactivated via the app eBike
Flow.
Assembly
Checking the speed sensor (see figure A)
Speedsensor (slim)
The speed sensor (2) and its CenterLock magnet (4) or
spoke magnet (3) are mounted ex works in such a manner
that the magnet, after a turn of the wheel, moves past the
speed sensor with a clearance of at least 2 mm, yet no more
than 15 mm.
0 275 007 3D4 | (19.02.2024)
Drive Unit
Performance Line CX
BDU3840
W
250
Nm
85
V
36
°C
–5 to +40
°C
+10 to +40
IP55
kg
2.8
V
12
W
18
If any structural changes are made, the correct distance
between the magnet and the sensor must be complied with
(see figure A).
Note: Make sure you do not damage the sensor or the sensor
holder when fitting or removing the rear wheel.
When changing a wheel, make sure that the sensor cable is
routed so that it is not under tension and has no kinks.
The CenterLock magnet (4) can only be removed and rein-
serted up to 5 times.
Rim magnet
Note: The rim magnet's alignment with the rim must not be
changed (see figure A).
If a rim magnet is installed, no sensor is required to detect a
wheel turn. The drive unit itself detects when the magnet is
close to it and calculates the speed and any other data re-
quired from the frequency of the emergence of the magnet
field.
Since the drive unit is sensitive to magnetic fields, avoid
other magnetic fields in the vicinity of the drive unit (e.g.
magnetic clipless pedals, magnetic cadence sensors, mag-
netic or magnetised tools, etc.) in order to prevent disrup-
tion to the drive unit.
Operation
A control unit from the system generation the smart system
is required for the starting operation of the eBike. Please ob-
serve the operating instructions of the control unit and, if ne-
cessary, additional components from the system generation
the smart system.
Notes on Cycling with Your eBike
When does the drive work?
The drive assists your cycling only when you are pedalling. If
you do not pedal, the assistance will not work. The drive
power always depends on the pedalling force and cadence
you apply.
If you apply less force or a lower cadence, you will receive
less assistance than if you apply a lot of force or a higher ca-
dence. This applies irrespective of the riding mode.
The drive automatically switches off at speeds over
25 km/h. When the speed falls below 25 km/h, the drive
automatically becomes available again.
An exception applies to the walk assistance function, in
which the eBike can be pushed at low speed without ped-
alling. The pedals may rotate when the walk assistance is in
use.
You can also use the eBike as a normal bicycle without as-
sistance at any time, either by switching off the eBike or by
setting the riding mode to OFF. The same applies when the
eBike battery is drained.
Interaction between the Drive Unit and Gear-shifting
The gear shifting should be used with an eBike in the same
way as with a normal bicycle (observe the operating instruc-
tions of your eBike on this point).
Bosch eBike Systems
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