Bosch BULLS 650-185, Operating Instructions Manual

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36
Description
3.3.4 Wheel
Figure 21: Visible wheel components
1
2
3
4
5
6
T i r e s
Rim
Spoke
Spoke nipples
Hub
Valve
The wheel comprises the wheel itself, an inner
tube with a valve and a
tire
.
3.3.4.1
Tires
The
tire
forms the outer section of the wheel.
Tires
differ in their tread, depending on their
intended use.
Tread
The tread has little influence on riding
characteristics on a smooth road. In this case, the
grip between the road and
tire
is mainly due to the
rolling friction between the rubber and the road
surface.
Unlike cars, a
n ebike
will not aquaplane. The
tread contact is much smaller and the contact
pressure much higher. Theoretically, aquaplaning
will not occur until speeds of 200 km/h are
reached.
However, the tread is highly important on terrain.
In this case, the tread creates an interlock with the
ground. This is the only way possible to transmit
the driving, braking and steering forces. The tread
can also help improve control on dirty road
surfaces.
If a
tire
with a deep tread is used on asphalt, this
may make an unpleasant noise when the brakes
are used In such a case, the specialist dealer
needs to replace the
tire
with a new one with a
shallow tread.
Figure 22: Example: Information on
tires
Tire
pressure
The permitted pressure range is indicated on the
side of the
tire
. It is indicated in psi or bars.
The
tire
is only able to support the
ebike
if there is
adequate
tire
pressure. The
tire
pressure must be
adjusted to the rider and then checked on a
regular basis.
Tire
size
The
tire
size pressure range is indicated on the
side of the
tire
.
3.3.4.2 Rim
The rim is the metal profile on a wheel which
holds the
tire
, tube and rim band together. The
rim is joined to the hub with spokes.
In rim brakes, the outer surface of the rim is used
to brake.
3.3.4.3 Valve
Each wheel has a valve. Air is pumped into the
tire
via the valve. There is a valve cap on each
valve. The screw-on valve cap keeps out dust and
dirt.
1
2
3
6
5
4