HPA-Faip M 830 LL, Operator'S Manual

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158 M 830 LL - M 830 M User Manual
6 - Centring band . This is a small marking which indicates
the circumference of the top part of the bead and is
used as a reference to check exact tyre centring on
the rim after mounting.
7 - Protective band . This is a circumferential marking in
the area of the sidewall which is more exposed to
accidental rubbing.
8 - Sidewall. This is the area between the shoulder and
the centring band. It consists of a more or less thin
layer of rubber, which protects the casing plys from
lateral impact.
9 - Liner. This is a vulcanised, compound sheet, im-
permeable to air, inside tubeless tyres.
10 - Filling. This is a generally triangular rubber profile,
above the side ring; it provides rigidity for the bead
and gradually offsets the abrupt uneven thickness
caused by the side ring.
11 - Flap . This is the part of the casing ply around the
side ring and placed against the casing, to secure the
ply and prevent it from slipping.
12 - Foot . This is the innermost layer of the tread in
contact with the belt, or if the latter is not present
(conventional tyre) with the last casing ply.
13 - Shoulder. This is the outer part of the tread, between
the corner and start of the sidewall.
14 - Bead
. This is the part joining the tyre to the rim.
The bead point (a) is the inner corner. The spur (b)
is the outer part of the bead. The base (c) is the area
resting against the rim. The groove (d) is the concave
part against which the rim shoulder rests.
Tube type tyres. As a tyre has to contain pressurised
air for a fairly long time, an air chamber is used. The
valve for adding air and maintaining, controlling and
restoring air pressure is part of the chamber in this case.
Tubeless tyres. Tubeless tyres consist of a tyre with
inner sidewall lined with a thin layer of special im-
permeable rubber, called
liner . This liner helps to
maintain air pressure in the casing. This kind of tyre
must be mounted on a specific rim, to which the valve
is directly fixed.
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14
6
11
2
10
4
a
c
d
e
b