Royal Enfield 500 TWIN 1949, Workshop Maintenance Manual

Page: 101 / 110

ROYAL ENFIELD WORKSHOP MANUAL
Section L2 Page 4
When reassembling the cush drive the
entry of the vanes between the rubbers will
be facilitated if the latter are fitted into the
driving shell first and then tilted. The
rubbers should be liberally painted with
soapsuds to faciliate entry of the vanes.
When reassembling the cush drive coat
the inside of the bore of the sprocket/brake
drum liberally with grease where it fits over
the hub barrel and also put grease on the
inner face of the lockring, 10097. The three
Simmonds nuts should be tightened down
solid as there is a shoulder on the stud
which prevents tightening of the nuts from
locking the operation of the cush drive.
11. Reassembly of Brake Shoes, Pivot Pin
and Operating Cam into Cover Plate
No difficulty should be experienced in
carrying out these operations. Make sure that
the pivot pin is really tight in the cover plate
and put a smear of grease in the grooves of
the pivot pin and on the operating face of the
cam; also on the cylindrical bearing surface
of the operating cam if this has been
removed. Fit the operating lever and
trunnion on its splines in a position to suit
the extent of wear on the linings and secure
with the nut. The range of adjustment can be
extended by moving the lever on to a
different spline.
12. Centering Cam Housing
Note that the bolt holes in the cam
housing are slotted, thus enabling the brake
shoe assembly to be centered in the drum. It
is not intended that on rear brakes the cam
housing should be left free to float but the
shoes should be centered by leaving the
screws just short of dead tight. The brake
cover plate assembly with the shoes should
then be fitted over the spindle into the brake
drum and the brake applied as hard as
possible by means of the operating lever.
This will centre the shoes in the drum. The
screws should then be tightened dead tight
and secured with the locknuts. If the shoes
are not correctly centered the brake will be
either ineffective or too fierce, depending on
whether the trailing or leading shoe first
makes contact with the drum. With the brake
assembly correctly centered and the screws
securing the cam housing correctly tightened
wear on both linings should be
approximately equal.
13. Final Reassembly of Hub before
replacing Wheel
Before replacing the felt washers which
form the grease seals, pack both bearings
with grease.
Recommended greases are Castrolease
(Heavy), Mobilgrease (No. 4), Esso Grease,
Energrease C3 or Shell Retinax A. These
are all medium heavy lime soap or
aluminium soap greases. The use of H.M.P.
greases which have a soda soap base is not
recommended as these tend to be slightly
corrosive if any damp finds its way into the
hubs.
Make sure that the inside of the brake
drum is quite free from oil or grease, damp,
etc. Replace the felt washers, distance
collars, the brake cover plate assembly,
speedometer drive gearbox, distance
collars, chain adjuster cams, the loose
section of the spindle and the spindle nut.
The wheel is then ready for reassembly into
the machine.
14. Wheel Rims
The rim fitted to both types of wheel is
WM2-19 in. pierced with 40 holes for spoke
nipples. The internal width is 1.580in. and
the diameter after building 19.062 in., the
tolerance on the circumference of the rim
shoulders where the tyre fits being
59.930/59.870 in. The standard steel
measuring tape for checking rims is 5/16 in.
wide, .011 in. thick and its length is
59.964/59.904 in.
Note that two makes of rim are used
"Dunlop" and "Palmer Jointless." These
differ in the positions of the pierced spoke
holes. The Dunlop rims have a group 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.
Palmer rims have the holes alternately
spaced either side of the centre line. Both
rims are interchangeable and both use the
same length spokes but the method of lacing
the wheel is different (see paragraph 16).
Neither type of rim is symmetrical and care
must be taken that they are built the right
way round into the wheel.
15. Spokes
The spokes are of the single butted type
8-10 gauge with 90° countersunk heads,
angle of bend 95°100°, thread diameter
.144in., 40 threads per inch, thread form
British Standard Cycle. Spoke lengths are
as follows.
"Meteor 700," and "500 Bullet,"
Cush drive side, 7.3/4 in.
Spoke flange side 8.1/2 in.
"500 Twin" and "350 Bullet,"
Cush drive side, 7.7/8 in.
Spoke flange side 8.5/8 in.
16. Wheel Building and Truing
The spokes are laced one over three. The
wheel must be built central in relation to the
outer faces of the distance collars which fit
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