Spare tyres are not included in the inspection.
However, if a defect is seen, thevehicle presenter should be notified.
The owner should be advised of loose or missing
security bolts.
Serious under-inflation of tyres is not a
reason for failure. However, the tester may decide not to conduct
a brake test if tyre damage is likely, or a headlamp test if alignment
could be affected. Advise the owner.
A tyre repair may be drawn to the attention
of the vehicle presenter.
Examples of unsuitable tyres:
a. side car tyres or car tyres on a solo machine (note side car
outfits may be fitted with 'solo' type tyres on any wheel);
b. Motocross or similar tyres, i.e. tyres where the space between
tread blocks is substantially greater than the size of the blocks
themselves; which do not have MST (multi service tyre) with an 'E'
in a circle or an e in a rectangle moulded into or on to the tyre
wall
c. tyres designated by their manufacture as unsuitable for road
use e.g. racing tyres or those marked NHS or NOT FOR HIGHWAY USE
on the sidewall.
d. a tyre specifically designed for front wheel use fitted to the
rear wheel;
e. a bias belted tyre fitted to the front with a cross-ply tyre
fitted to the rear wheel
f. a radial tyre fitted to the front and a cross ply or bias belted
tyre fitted to the rear wheel
On radial tyres care should be taken to distinguish
between normal manufacturing undulations in the carcass and lumps
or bulges caused by structural deterioration.
Where the engine capacity is not greater than 50cc,
tread depth may be less than 1 mm, if the tread pattern is clearly
visible around the entire circumference and across the whole breadth
of the tread.
Directional tyres these tyres must be fitted
in accordance with the instructions on the sidewall. The direction
of forward rotation is indicated by an arrow, words or both.
Tyres which do not meet the three-quarters width
rule when new must have a minimum of 1 mm tread over the
whole of the original tread pattern.
'Breadth of tread' means that part of the
tread which can contact the road in normal use. Including cornering.
'Tread pattern' excludes tie-bars, tread wear
indicators, features designed to wear out substantially before the
rest of the pattern and other minor features. Original tread pattern
must be taken into account when assessing tread wear.
The position of tread wear indicators
are normally marked TW1 on the side wall of the tyre in line with
the tread wear indicator-
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1. Examine the tyres for type and suitability. (see information
column)
2. With the wheels raised clear of the ground, rotate each slowly
and examine each tyre for:
a. cuts. lumps, bulges, tears or exposure of the ply or cord, separation
of the tread
b. incorrect seating in the wheel rim
c. valve condition and alignment
d. recutting of the tread
e. fitment in the correct direction of rotation
3. Check that there is a visible tread pattern around the complete
circumference of the tyre- Ensure that the tread depth meets the
requirements using a depth gauge.
4. Check for signs of fouling of tyres on other components.
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1. An unsuitable tyre.
(see information column)
(i) A tyre has a cut longer than 25mm or 10% of the section width
of the tyre. whichever is the greatest, and deep enough to reach
the ply or cord.
(ii) A tyre with a lump, bulge or tear caused by separation or partial
failure of its structure, including lifting of the tread, (see information
column).
(iii) Any ply or cord exposed
b. a tyre not correctly seated in the wheel
rim
c. a seriously damaged or misaligned valve stem which could cause
sudden deflation of the tyre
d. a tyre with a recut tread
e. A tyre not fitted in accordance with the direction of rotation
marked on the sidewall (see information column).
3.
(i) the tread pattern is not clearly visible over the whole tread
area. (see information column)
(iij The depth of tread is not at least
Imm throughout a continuous circumferential band measuring at least
three quarters of the breadth of the tread, (see information column).
4. A tyre fouling another component
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