BMW AG Motorcycle (K1100LT, K1100RS). Manual - part 15

13.5

Adjusting idle speed

L

 Note:

The basic setting (ignition, valve clearance) must be 
correct.

•

Remove knee pad.

•

Remove left side fairing.

•

Remove protective caps (1) at the vacuum con-
nections.

•

Connect connection hoses of the Synchrotester, 
BMW No. 13 0 800, one after the other (note 
hose markings 1-4 on tester housing).

•

Connect tester to vehicle with the corresponding 
adapter lead.

•

Start engine and run at a standstill for app. 10 
minutes if not already warm.

e

 Caution:

Do not run for more than 20 minutes at a standstill.

•

Run the engine at idle speed.

•

Select “bar diagram” and maximum resolution.

L

 Note:

If the differences between the individual columns 
are too great (more than 2...5 mm 
(0.07874...0.19685 in)), switch over to curve display 
and compare the individual cylinders with each oth-
er; perform fault diagnosis procedure if necessary.

•

Repair any faults found.

e

 Caution:

Throttle adjusting screw (2) is secured with lacquer 
and must not be turned.

•

Adjust synchronisation and idle speed by turning 
the air control screws until the bars/curves are at 
the same height; adjust engine idle speed.

Idle speed

......................................... 950 ± 50 rpm

LT000280

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1

13.6

Checking start speed increase 
(choke), adjusting if necessary

Checking start speed increase

•

Remove left battery cover.

•

Set speed increase to limit stop (stage 2).

e

 Caution:

Screw (2) is sealed with lacquer and must not be 
turned.

L

 Note:

Stop face (1) must be in contact with screw (2) and 
the cable must have no play; if this is not the case, 
play at the cable must be adjusted.

•

Check stop face (1).

Adjusting start speed increase

•

Set speed increase to limit stop (stage 2).

•

Loosen locknut (3).

•

Press lever with stop face (1) against screw (2).

•

Turn adjusting screw (4) until there is no play at 
the cable.

•

Retighten locknut (3)

.

LT130030

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1

3

2

13.7

Adjusting CO value

L

 Note:

Engine must be at operating temperature (85 °C).
Basic settings (ignition timing, valve clearances) 
must be correct.

•

Insert the measuring probe (arrow) app. 30 cm 
(12 in) into the silencer (muffler).

e

 Caution:

Do not perform this measuring work in an enclosed 
space: risk of asphyxiation.

L

 Note:

If the air extraction equipment is unsuitable, it may 
falsify the measurement.

•

Run the engine at idle speed.

e

 

Caution:

Adjusting screw (2) has no limit stop in both direc-
tions.

•

Turn adjusting screw (2) to obtain correct CO.

L

 Note:

Turn in direction (1) for a richer mixture; the CO value 
will rise to a maximum. Turning further in direction (1) 
has no effect on the CO value. 
Turn in direction (3) for a leaner mixture; the CO val-
ue will drop to a minimum. Turning further in direc-
tion (3) will cause the engine’s emergency-run 
programme to operate, but has no influence on the 
CO value.

e

 Caution:

If the engine’s emergency-run programme operates, 
fault 1111 will be memorised in the engine control 
unit.

•

If necessary, carry out fault diagnosis, rectify the 
fault and cancel the memory entry.

•

Using the BMW Synchrotester, adust idle speed 
at the recirculating-air screws.

CO value

................................... 1,5 ± 0,5 

% by vol.

Idle speed

..........................................950 ± 50 rpm

LT000290

LT000300

2

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3

13.8

Removing/installing and checking/
adjusting throttle position sensor

Removing and installing throttle posi-
tion sensor

•

Unscrew the throttle position sensor and pull it 
off the throttle shaft.

•

Loosen wire keeper (1) and pull off multi-pin plug 
(2).

•

Install in the reverse order of work.

e

 Caution:

If the throttle position sensor has been removed, the 
basic settings must be checked and corrected if 
necessary after installing it again.

L

 Note:

See the booklet “BMW Diagnosis, Motronic MA 2.1 
with oxygen sensing” or “without oxygen sensing”, 
or the booklet “BMW Diagnosis MA 2.2”.

Checking trottle position sensor

•

Connect the diagnostic cable.

•

Press the left switch on the switch cabinet up to 
the detent position.

•

Switch on the ignition.

•

[MA 2.1]

 If the temperature warning light comes 

on, the throttle position sensor is correctly adjust-
ed.

•

[MA 2.1]

 If the temperature warning light does 

not come on, re-adjustment is needed.

•

[MA 2.2] 

If small zeroes are visible on the tester 

display, the throttle position sensor is correctly 
adjusted.

•

[MA 2.2] 

If no zeroes are visible, check the throt-

tle end stops and re-adjust.

Adjusting throttle position sensor

L

 Note:

Only adjust if the throttle position sensor was re-
moved or renewed.

•

Loosen the fastening for the sensor at the throttle 
rail.

•

Turn the sensor to the left or right until

 [MA 2.1] 

the temperature warning light comes on or 

[MA 2.2]

 small zeroes appear on the display.

•

Tighten the sensor in this position.

•

Pull off the diagnostic cable.

LT130060

2

1

13.9

Removing and installing air cleaner 
insert

•

Remove both knee pads.

•

Remove fuel tank.

•

Remove left and right heat-insulating bulkhead.

•

Release front clip (1) and both rear clips (2).

•

Slightly raise top section of air cleaner housing 
and remove air cleaner element.

L

 Note:

Note installed position of air cleaner element: letter-
ing at rear, arrow marking “TOP/OBEN”.

LT130070

1

2

13.10

Removing and installing air cleaner 
housing

•

Remove both knee pads.

•

Remove fuel tank.

•

Remove left and right side fairings.

•

Remove intake air guide.

•

Remove fairing retaining bracket on right.

•

Remove air cleaner.

•

Loosen wire retainer (1), disconnect multiplug (2) 
at air temperature sensor.

•

Release hose clips (3) at the air intake lines.

•

Loosen hose clip (4), detach crankcase breather 
ventilation hose.

LT130080

2

1

3

4

3

13.11

•

Loosen and pull off oil return pipe (5).

•

Loosen and pull off air return pipe (6).

•

Pull top section of air cleaner housing (7) out to 
the right.

•

Remove bottom section of air cleaner housing.

•

Install in the reverse order of removal.

X 

Tightening torques:

Bottom section of air cleaner housing

.......... 21 Nm

Intake air pipe

................................................ 9 Nm

LT130090

5

6

7

13.12

Removing and installing throttle rail

•

Remove fuel tank.

•

Remove left fairing side section.

•

Remove left-hand heat-insulating bulkhead.

•

Release fuel hose (1) at injection rail.

•

Release injection rail (2) at cylinder head and pull 
out together with injectors.

•

Disconnect multiplug at throttle sensor.

L

 Note:

Only remove throttle sensor if it is to be replaced 
(basic setting necessary).

•

Detach throttle cable (3).

•

Detach operating cable (4) for start speed in-
crease.

•

Release hose clips at the air intake lines, loosen 
at the throttle coupling.

•

Remove throttle rail from stub pipe.

•

Pull air return pipe (5) off throttle rail.

•

Disconnect indicator lamp plug connection for 
start speed increase.

•

Install in the reverse order of removal.

L

 Note:

Do not change the location of the hose clips on the 
throttle coupling unions.
Firmly tighten hose clips at the air intake lines with 
special tool, BMW No. 31 1 500.

LT130100

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4

2

LT130110

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