Tech 25
controlled by the tension adjusting nut. Turning the tension adjusting nut
clockwise while keeping the cam lever from rotating increases clamping force;
turning it counterclockwise while keeping the cam lever from rotating reduces
clamping force. Less than half a turn of the tension adjusting nut can make
the difference between safe clamping force and unsafe clamping force.
WARNING: The full force of the cam action is needed to clamp the
wheel securely. Holding the nut with one hand and turning the lever
like a wing nut with the other hand until everything is as tight as you
can get it will not clamp a cam action wheel safely in the dropouts.
See also the first WARNING in this Section, p. 18.
b. Adjusting the cam-and-cup mechanism (fig. 8b)
The cam-and-cup system on your front wheel will have been correctly
adjusted for your bicycle by your dealer. Ask your dealer to check the
adjustment every six months. Do not use a cam-and-cup front wheel on
any bicycle other than the one for which your dealer adjusted it.
3. Removing and Installing wheels
WARNING: If your bike is equipped with a hub brake such as a rear
coaster brake, front or rear drum, band or roller brake; or if it has an
internal gear rear hub, do not attempt to remove the wheel. The
removal and re-installation of most hub brakes and internal gear hubs
requires special knowledge. Incorrect removal or assembly can result
in brake or gear failure, which can cause you to lose control and fall.
CAUTION: If your bike has a disc brake, exercise care in touching the rotor
or caliper. Disc rotors have sharp edges, and both rotor and caliper can get
very hot during use.
a. Removing a disk brake or rim brake Front Wheel
(1) If your bike has rim brakes, disengage the brake’s quick-release
mechanism to increase the clearance between the tire and the brake pads
(See Section 4.C g. 11 through 15).
(2) If your bike has cam action front wheel retention, move the cam lever
from the locked or CLOSED position to the OPEN position (gs. 8a & b).
If your bike has through bolt or bolt-on front wheel retention, loosen the
fastener(s) a few turns counter-clockwise using an appropriate wrench,
lock key or the integral lever.
(3) If your front fork has a clip-on type secondary retention device, disengage
it and go to step (4). If your front fork has an integral secondary retention
device, and a traditional cam action system (g. 8a) loosen the tension
adjusting nut enough to allow removing the wheel from the dropouts. If
your front wheel uses a cam-and-cup system, (g. 8b) squeeze the cup
and cam lever together while removing the wheel. No rotation of any part is
necessary with the cam-and-cup system.
You may need to tap the top of the wheel with the palm of your hand to
release the wheel from the front fork.
WARNING: Riding with an improperly secured wheel can allow the
wheel to wobble or fall off the bicycle, which can cause serious injury
or death. Therefore, it is essential that you:
1. Ask your dealer to help you make sure you know how to install and
remove your wheels safely.
2. Understand and apply the correct technique for clamping your wheel
in place.
3. Each time, before you ride the bike, check that the wheel is securely
clamped.
The clamping action of a correctly secured wheel must emboss the surfaces of
the dropouts.
1. Front Wheel Secondary Retention Devices
Most bicycles have front forks which utilize a secondary wheel retention
device to reduce the risk of the wheel disengaging from the fork if the wheel
is incorrectly secured. Secondary retention devices are not a substitute for
correctly securing your front wheel.
Secondary retention devices fall into two basic categories:
a. The clip-on type is a part which the manufacturer adds to the front wheel hub
or front fork.
b. The integral type is molded, cast or machined into the outer faces of the front
fork dropouts.
Ask your dealer to explain the particular secondary retention device on your bike.
WARNING: Do not remove or disable the secondary retention device.
As its name implies, it serves as a back-up for a critical adjustment.
If the wheel is not secured correctly, the secondary retention device
can reduce the risk of the wheel disengaging from the fork. Removing
or disabling the secondary retention device may also void the warranty.
Secondary retention devices are not a substitute for correctly securing your
wheel. Failure to properly secure the wheel can cause the wheel to wobble
or disengage, which could cause you to loose control and fall, resulting in
serious injury or death.
2. Wheels with cam action systems
There are currently two types of over-center cam wheel retention mechanisms:
the traditional over-center cam (g. 8a) and the cam-and-cup system (g. 8b).
Both use an over-center cam action to clamp the bike’s wheel in place. Your
bicycle may have a cam-and-cup front wheel retention system and a traditional
rear wheel cam action system.
a. Adjusting the traditional cam action mechanism (fig. 8a)
The wheel hub is clamped in place by the force of the over-center cam
pushing against one dropout and pulling the tension adjusting nut, by way
of the skewer, against the other dropout. The amount of clamping force is
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