Bosch eBike Active Line BDU310 - Removing Drive Unit (BDU250 C;255 C)

B A C D
197
6.8 Installing Drive Unit (BDU310/350) 6.9 Removing the Drive Unit (BDU250C/255C)
Removing the chainring
The chainring spider may
only be loosened and tight-
ened by a trained specialist
using the original Bosch
Lock Ring Tool!
1. Remove the crank arms (Allen
key size 8, ISIS crank-puller).
2. Block the rear wheel, e.g.
secure the brake lever with a
cable tie or similar.
3. Unscrew the lock ring (A) with
the lock ring tool (B).
Left-hand thread!
4. Remove the chain.
5. Remove the O-ring (C) and
carefully check it for damage.
Only reuse O-rings if they are
intact.
6. Remove the chainring (D).
X Allen key size 8
X ISIS crank-puller,
e.g. Park Tool CCP 44
X Bosch Lock Ring Tool (with
1/2" drive)
Not for Active Line
(BDU310), Active Line Plus
(BDU350) or Classic+ Line
Work steps Tool
6.9 Removing Drive Unit
(BDU250C/255C)
Lock ring for
model year 2015
Lock ring as of
model year 2016
Information about the lock
rings
Lock ring made of plastic up to
model year 2014
X Tightening torque: 20–25 Nm on
non-greased threads
Lock ring made of aluminum as of
model year 2015 in combination
with an O-ring
X Prevents damage resulting from
incorrect installation and use of
improper tools.
X Tightening torque: 20–25 Nm on
greased threads
New lock ring as of model year
2016 enables assembly starting
with chainring size 14.
X Can be used for all Bosch eBike
and chainring sizes.
X Tightening torque: 20–25 Nm on
greased threads
6
INSTALLATION/
REMOVAL