Royal Enfield 250 CLIPPER, Руководство по техническому обслуживанию мастерской

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ROYAL ENFIELD WORKSHOP MANUAL
PAGE 87
The spoke holes are arranged in groups of three
holes on one side of the centre line, then a single
hole on the other side, a further group of three
and a single hole and so on. Care must be taken
that the rim is built the right way round into the
wheel. The rim diameter after building is 17.06 in.,
the tolerances on the circumference where the
tyre fits being 53.642/53.582 in. The standard
steel measuring tape for checking rims is ¼ in.
wide, .011 in. thick and its length is 53.702/53.642
in.
The "250 Trials" model is fitted with aWM3-18
rim having a diameter after building of 18.06 in.,
the tolerances on the circumference being 56.783/
56.723 in. and the length of the measuring tape
56.843/56.783 in.
14. Spokes
The spokes are of the single-butted type, 8-10
guage with 90° countersunk heads, thread diameter
.144 in., 40 threads per inch, thread form British
Standard Cycle. For the 17 in. rim the spoke length
is 6
3
/
4
in. on the cush drive side and 7½ in., on the
spoke flange side. For the 18 in. rim the spoke
lengths are 7¼ in. and 8 in. respectively. All spokes
initially have an angle of bend of approximately
100°; those on the outside of the spoke flanges are
hit with a hide or wooden mallet after building the
wheel but before final truing so as to give a more
acute angle of bend of approximately 80°.
15. Wheel Building and Truing
The spokes are laced one over three and the
wheel must be built central in relation to the faces
of the distance collars which fit between the fork
end. The rim should be trued as accurately as
possible, the maximum permissible run-out both
sideways and radially being plus or minus
1
/
32
in.
Fig. 5 shows the lacing when using Dunlop
rims. The key to correct lacing is the inside
spokes to the large flange on the cush drive shell
which must slope in the direction shown in Fig. 5.
With the Dunlop rim this spoke goes to the
middle hole of one of the groups of three (see
Subsection 14) and the rim must be built into the
wheel so that these groups of three holes are on
the right of the centre line when the cush drive is
on the left, i.e., the inside spokes to the large
flange cross from the left to the right of the
centre line.
16. Tyres
The standard tyre is Dunlop 3.25-17 in.
Universal tread. When removing the tyre always
start close to the valve and see that the edge of
the cover at the other side of the wheel is pushed
down into the well in the rim. When replacing the
tyre, fit the part by the valve last, also with the
edge of the cover at the other side of the wheel
pushed down into the well.
If the correct method of fitting and removal of
the tyre is adopted it will be found that the covers
can be manipulated quite easily with the small
levers supplied in the tool-kit. The use of long
levers and/or excessive force is liable to damage
the walls of the tyre. After inflation make sure that
the tyre is fitting evenly all the way round the rim.
A line moulded on the wall of the tyre indicates
whether or not the tyre is correctly fitted. If the
tyre has a white mark indicating a balance point
this should be fitted near the valve.
A 4.00-18 in. tyre is fitted to the 18 in. wheel of
the "250 Trials."
17. Tyre Pressures
The load which the tyre will carry at different
inflation pressures is shown below:
18. Lubrication
A greasing point is provided in the centre of
the hub barrel. Unless the barrel is packed full
with grease on assembly (Which is apt to lead to
trouble through grease finding its way past the felt
seals on to the brake linings) this greasing point is
of little value and the best way to grease the
bearings is by packing them with grease after
dismantling the hub as described above.
Note that the brake cam is drilled for a grease
passage but the end of this is stopped up with a
countersunk screw instead of being fitted with a
grease nipple. This is done to prevent excessive
greasing by over-enthusiastic owners. If the cam is
smeared with grease on assembly it should require
no further attention but in case of necessity it is
possible to remove the screw, fit a grease nipple
in its place and grease the cam by this means.
L10
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