BMW Mountain Bike Enduro Owner's Manual page 56

The initial tension of most forks with coil springs or elastomer fillings can
be altered to a limited degree by adjusting the preload knob located on
the fork crown connecting the stanchion tubes. In the event there is no
adjusting device, the coil spring or elastomer filling need to be replaced.
In the case of oil/air forks, the spring rate is adjusted by the air pressure
((c) p. 51). The pressure must be checked at regular intervals
in the fork
with a special shock pump which is normally made available by the fork
manufacturer. Please follow the recommendations of the manufacturer.
Ride your bicycle on different kinds of surface and check afterwards the
((d) p. 51). The difference is the rear shock's travel
travel of the cable tie
you have used. If the cable tie has moved a few millimetres only, your
fork is too firm. Reduce the air pressure of air sprung forks or the initial
spring tension of coil springs. If your rear shock is still too firm, have the
springs replaced.
If the cable tie has moved along the entire travel range
hear the fork hit the end of its travel, the spring is too soft. In this case
the initial spring tension/pressure must be increased (b). If the adjust-
ment range of the coil springs is too small, have the springs replaced at a
bicycle specialist shop of your trust.
Check the pressure of air sprung forks at regular intervals and follow the
recommendations of the manufacturer. If the available setting options do
not cover your needs, you will need to replace the springs or dampers.
Many manufacturers have tuning and retrofitting kits on offer. If you are
a
52
(a)
or if you can
b
in doubt or if you have any questions, please contact a bicycle specialist
shop of your trust! When replacing any parts be sure to only use parts
that bear the appropriate mark and, to be on the safe side, original spare
parts. Your BMW partner will be pleased to order the original spare parts
for you!
Fork manufacturers include instructions with their deliveries.
Read them carefully before changing any settings or doing any
maintenance work on your rear shock.
The suspension fork should be set up and adjusted in such
a way that it does not reach the end of its travel (known as
bottom out). A spring rate which is too soft (or too low an air
pressure) can usually be heard or felt as a "clunk" type noise.
This noise is caused by the sudden complete compression of
the suspension fork as it reaches bottom out. If the suspension
fork frequently reaches bottom out, it will become damaged
over time, and so will the frame.
(c)
Suspension forks are designed in a way to absorb shocks.
If the fork is too rigid and jammed, the terrain induced shocks
pass directly into the frame without any damping. The frame is
normally not designed to withstand such undamped stresses.
If your bicycle is equipped with a suspension fork including
lockout (d), you should keep in mind not to activate the lockout
function when riding over rough terrain, but only when riding
over smooth terrain (tarred roads, smooth tracks).
c
d