BMW AG Motorcycle (R 850 C, R 1200 C). Manual - part 18

23.22

Assembling gearbox

Installing input, output and
intermediate shaft

•

Insert selector shaft (1) into intermediate shaft (2).

•

Align input, output and intermediate shafts so 
that their gear teeth mesh and the selector fork is 
in the position illustrated.

•

Push slip-over sleeve, BMW No. 23 4 712, on to 
the input shaft splines.

L

 Note:

This is only necessary if the shaft sealing ring is in-
stalled.

•

Heat the bearing points on the cover to 
80 … 100 °C (176 ... 212 °F).

•

Insert the input, output and intermediate shafts 
together.

e

 Caution:

Check that the gearbox shafts are correctly seated.

•

Install the 1st/3rd gear and 2nd/4th gear selector 
forks.

C230100

h

80…100

w

23 4 712

C230070

1

2

23.23

Installing selector shaft

•

Place a spacing washer of the determined thick-
ness in position and install selector shaft (1). 

•

Engage torsion spring (2) in the housing.

Installing selector drum

•

Place a spacing washer of the determined thick-
ness and the input-side thrust washer on selec-
tor drum (6) and secure with a small amount of 
grease.

•

Swing locking lever (8) out towards the edge of 
the cover and install the selector drum.

•

Swing locking lever (8) towards selector drum (6) 
and engage it in position together with guide 
plate (7).

•

Place shift forks (5, 10) in the guide tracks.

•

Install selector shafts (3).

•

Install locking pin (11).

•

Place thrust washer (4) on the selector drum.

C230060

1

2

C230030

3

5

9

3

4

10

7

8

6

11

23.24

Assembling gearbox housing

•

Install reamed pins (arrows) in cover.

•

Install breather tube (1) in housing cover.

e

 Caution:

The sealing faces must be free from oil or grease.
The sealing material sets within 30 minutes; within 
this time, place the housing in position and screw it 
down.

•

Using the metering device, apply Loctite 5203 
surface sealant to the cover joint face.

•

Place slip-over sleeve, BMW No. 23 4 732, on 
the output shaft.

•

Place slip-over sleeve, BMW No. 23 4 712, on 
the input shaft.

•

Place slip-over sleeve, BMW No. 23 4 612, on 
the selector shaft.

•

Heat the bearing seats in the housing to 
80 … 100 °C (176 ... 212 °F) and place the hous-
ing on the cover.

C230090

1

23 4 732

23 4 712

23 4 612

C230020

h

80…100

w

23.25

•

Insert screws (8) and tighten in a crosswise pat-
tern.

•

Install neutral indicator (4) and clip wire (3) into 
position.

•

Install breather (1).

e

 Caution:

Clean metal particles off the magnet in drain 
plug (7).

•

Insert oil drain plug (7). 

•

Insert oil filler and level check plug (2) with a new 
sealing ring.

•

Install shift lever (6) in the correct position.

L

 Note:

In the correct position the mark on the selector lever 
(dot) is aligned with the mark on the selector shaft 
(line).
After assembling the gearbox, perform a functional 
check.

C230012

1

4

7

6

5

3

8

2

C230130

6

23.26

31.1

Contents

Page

31

Technical data 

................................................................................................................................3

Removing and installing telescopic fork 

.........................................................................5

Removing and installing telescopic fork

 ...............................................................................5

Removing and installing fork bridge .....................................................................................................5
Removing and installing pot-type joints  ...............................................................................................6
Removing and installing ball thrust bearing  .........................................................................................7

Removing and installing slider tube bridge

 .........................................................................8

Removing and installing ball joint  ........................................................................................................8

Checking friction at ball joint/ball thrust bearing

 ..............................................................8

Assembly specification for telescopic fork: ..........................................................................................9

Dismantling/reassembling telescopic fork 

..................................................................10

Dismantling telescopic fork

 ......................................................................................................10

Assembling telescopic fork

 ......................................................................................................10

Measuring telescopic fork 

.....................................................................................................11

Check slider tube bridge  ...................................................................................................................11
Checking runout of fixed tube  ...........................................................................................................11

Removing and installing leading link 

...............................................................................12

Dismantling/reassembling leading link 

..........................................................................12

Removing and installing front suspension strut 

........................................................12

31 Front fork

31.3

31

Technical data

R 850 C

R 1200 C

Front suspension

Type

BMW Telelever with external suspension strut

Telescopic fork

Front wheel caster in normal-load position

mm (in) 86 (3.39)

Steering lock angle

° 2  x  38

Total suspension travel

mm (in) 144 (5.67)

Fixed tube surface

Hard chrome plated

Extl. dia. of fixed fork tubes

mm (in) 35.0 (1.38)

Maximum permissible runout of fixed fork 
tube

mm (in) 0.4 (0.016)

Telescopic fork oil – approved grades

BMW telescopic fork oil

Fill quantity in each fork leg

l (Imp. pint/

US quart) 0.470 (0.8275/0.4966)

Suspension strut

Type

Suspension strut with coil spring and twin-
tube, gas-filled shock absorber 

31.5

Removing and installing telescopic 
fork

Removing and installing telescopic 
fork

•

Remove front wheel.

•

Remove mudguard.

•

[ABS] Detach sensor.

•

Detach brake line retainer.

•

Heat leading link mount at front to max. 120 °C 
(248 °F) and unscrew.

•

Force off cap from fork bridge mount on frame 
with an M6 screw (thread length at least 25 mm/
0.98 in).

•

Unfasten fixed tube screw connection at fork 
bridge, preventing movement by holding hexa-
gon on fixed tube.

Removing and installing fork bridge

•

Unscrew fuel tank and pull to the rear.

•

Separate the connecting plug for the ignition/
steering lock in the central electrical equipment 
box.

•

Detach the instrument holder.

•

Detach the headlight holder.

•

Detach handlebar from fork bridge.

•

Force off cap from fork bridge mount on frame 
with an M6 screw (thread length at least 25 mm/
0.98 in).

•

Unfasten screw connection between fork bridge 
and frame.

L

 Note:

Remove complete, since the threaded journal is a 
press fit in the ball thrust bearing.

•

Remove fork bridge.

•

Remove ignition/steering lock.

a

........................................................... Group 51

31 5 600

C310020