BMW F800 R - Tyre Pressure Monitoring RDC

momentum take over and even
BMW Motorrad ABS is unable to
counteract their effects.
Tyre pressure
monitoring RDC
with tyre pressure monitoring
(RDC)
OE
Function
A sensor integrated into each
tyre measures the air temperat-
ure and the air pressure inside
the tyre and transmits this in-
formation to the control unit.
Each sensor has a centrifugal-
force tripswitch that does not
enable transmission of the meas-
ured values until the motorcycle
has accelerated to about 30 km/
h. The display shows -- for
each tyre until the tyre-pressure
signal is received for the first
time. The sensors continue to
transmit the measured-value sig-
nals for approximately 15 minutes
after the motorcycle comes to a
stop.
The control unit can adminis-
trate four sensors, so two dif-
ferent sets of wheels with RDC
sensors can be alternated on
the motorcycle. An error mes-
sage is issued if wheels without
sensors are fitted to a motorcycle
equipped with an RDC control
unit.
Temperature
compensation
Tyre pressure is a temperature-
sensitive variable: pressure in-
creases as tyre temperature rises
and decreases as tyre temper-
ature drops. Tyre temperature
depends on ambient temperat-
ure, on the style of riding and the
duration of the ride.
The tyre-pressure readings
shown by the multifunction
display are temperature-
compensated; the reference tyre
temperature for these readings
is always 20 °C. The air lines
available to the public in petrol
stations and motorway service
areas have gauges that do not
compensate for temperature; the
reading shown by a gauge of
this nature is the temperature-
dependent tyre pressure. In
most instances, therefore, these
gauge readings will not tally with
the pressures shown by the
multifunction display.
Tyre-pressure ranges
The RDC control unit differenti-
ates between three tyre-pressure
ranges, all of which are paramet-
erised for the motorcycle:
Tyre pressure within permitted
tolerance.
Tyre pressure close to limit of
permitted tolerance.
Tyre pressure outside permit-
ted tolerance.
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z Engineering details