wheeler Cross Operating Instructions Manual Download

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Adjusting the Spring Rate

To work perfectly, the rear shock

(a+b)

has to be adjusted to the

weight of the rider, the sitting posture and the intended use. Be sure to
have this adjustment carried out by your WHEELER bicycle dealer at the
moment of delivery.

Please bear in mind that the rear frame should sag a little under the
rider’s weight which is also referred to as “sag”. When the front wheel
passes through a depression in the ground, the spring extends and the
rear shock will smooth out the uneven surface. If the air pressure is
too high, this effect is lost, as the rear shock is already fully extended.
This means the loss of an important feature affecting both safety and
comfort, as the tyre shortly loses ground contact.

Cross-country and marathon racers usually run less sag than downhill-
ers or more comfort loving freeriders riding ofter over rough terrain. For
cross-country and marathon riding the rear shock should yield by about
10-25 % of its total travel, for enduro and freeriding by about 20-40 %.

To measure the sag you can use the rubber o-ring

(c)

that is usually on

the thinner immerging tube of the rear shock or mount a cable tie to the
thinner tube of the rear shock so that you can still slide it easily along
the tube’s exposed section.

Put on your usual cycling clothing (including packed rucksack, if neces-
sary), sit on your WHEELER bicycle, adopt your usual riding position
and lean against an object (railing, wall etc.) to ensure that you do not
topple over. Slide the rubber o-ring/cable tie downwards against the
wiper seal on the rear shock and get off the bicycle. Make sure the rear
shock does not compress any further. The distance between the rubber
o-ring/the cable tie and the wiper is the sag. Compare it to the total
travel of the rear shock (manufacturer specification). Now you can opt
for a harder or a softer adjustment of the suspension

(d)

The preload of most rear shocks with coil spring can be set to a limited
degree by an adjusting ring. If this is impossible and you do not succeed in
adjusting the desired sag, the coil spring must be replaced by a harder or
softer one. 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
WHEELER bicycle dealer will be pleased to help you.

In the case of air rear shocks, the spring rate is adjusted by the air
pressure in the rear shock. The pressure must be adjusted with a spe-
cial high-pressure pump with manometre

(e)

before your first ride and

readjusted in case the rider’s weight and/or the additional load will
change

(f)

. Note down the proper settings and check them at regular

intervals. Always observe the recommendations of the manufacturer
and do not exceed the maximum rear shock air pressure.

Do a test ride whenever you make any readjusting. Ride your bicycle
over a terrain with differing ground

(g+h)

and check the travel of the

rubber o-ring/cable tie afterwards. The distance to the wiper is the
maximum rear shock travel you have used. If the rubber o-ring/cable
tie has moved a few millimetres only, the setting of your rear shock is
too firm. Reduce the air pressure or in the case of rear shocks with coil
spring the preload. If your rear shock is still too firm, have the spring
replaced.

If the rubber o-ring/cable tie has moved along the entire travel range
or if you can hear the rear shock hit the end of its travel in the terrain,
the spring setting is too soft. In this case the spring preload/the pres-
sure must be increased. If the adjustment range of the coil spring is too
small, have the spring replaced by your WHEELER bicycle dealer.

Full suspension frames are designed in a way to absorb
shocks. If the rear shock is too rigid and jammed, the ter-

rain induced shocks pass directly into the frame without any
damping. The frame is normally not designed to withstand
such undamped stresses. If your rear shock has a lockout
mechanism, do not activate the lockout function when rid-
ing in rough terrain, but only when riding over smooth ter-
rain (roads, field tracks).

The rear shock should be set up and adjusted in a way that
it does not reach the end of its travel, i.e. bottom out, unless

in extreme cases. 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 rear shock as it reaches bottom out. If
the rear shock frequently reaches bottom out, it will sustain
damage over time, and so will the frame.

Rear shock manufacturers normally include instructions
with their deliveries. Please read the enclosed instructions

of the rear shock manufacturers, which you can find on the
enclosed CD.