BMW D7 Workshop Manual page 31

Timing gear adjustment
Correction is required in the following cases:
- If the collar pan constantly engages the cog
lightly, in the case of running the engine and
zero position of the decompression lever (Shaft
moves back and forth)
In this case, shorten the tappet somewhat and
dimension "A" will become larger (see figure)
- The decompression shaft is not rotated further
properly from position "2" of the handle
In this case, lengthen the tappet somewhat and
dimension "A" will become smaller (see figure)
Correct the position of the collar pan to the cog
(lateral distance) by a small movement of the
rocker arm shaft on the cylinder head plane.
NOTE
Choose distance "B" so that certain
functioning of the automatic system is
ensured. In the running position of the
engine (lever position "0") the collar pan
may not touch the cog.
Fix the cog segment on to the shaft so that the
cogged area is on the upper side when the flattened
part of the shaft points upward.
Adjust Decompression lever
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