BMW Motorrad R 1250 GS 2002, Rider'S Manual

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189
Measure the tyre tread depth
in the main tread grooves
with wear marks.
Wear indicators are built
into the main profile
grooves on each tyre. The tyre
is worn out when the tyre tread
has worn down to the level of
the marks. The locations of
the marks are indicated on the
edge of the tyre, e.g. by the
letters TI, TWI or by an arrow.
If the tyre tread is worn to min-
imum:
Replace tyre or tyres, as ap-
plicable.
Checking spokes
with cross-spoked wheels OE
Place the motorcycle on its
stand on firm, even ground.
Use a screwdriver handle or
similar object to brush over
the spokes and pay attention
to the sequence of sounds.
If the sequence of sounds is
irregular:
Have the spokes checked
by a specialist workshop,
preferably by an authorised
BMW Motorrad Retailer.
WHEELS
Effect of wheel size on
chassis and suspension
control systems
Wheel size is very important as
a parameter for the ABS run-
ning-gear control system. In
particular, the diameter and
the width of a vehicle's wheels
are programmed into the con-
trol unit and are fundamental
to all calculations. Any change
in these influencing variables,
caused for example by a switch
to wheels other than those in-
stalled ex-works, can have seri-
ous effects on the performance
of the control systems.
The sensor rings are essential
for correct road-speed calcula-
tion, and they too must match
the motorcycle's control sys-
tems and consequently cannot
be changed.
If you decide that you would
like to fit non-standard
wheels to your motorcycle,
it is very important to con-
sult a specialist workshop
beforehand, preferably an
authorised BMW Motorrad
retailer. In some cases, the
data programmed into the
control units can be changed to
suit the new wheel sizes.