Royal Enfield 350 BULLET 1949, Workshop Maintenance Manual

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ROYAL ENFIELD WORKSHOP MANUAL
Section L2 Page 2
the wheel out of the fork ends, tilting it so as to
disengage the end of the brake shoe pivot pin from
the slot in the fork end.
When replacing the wheel make sure that the dogs
on the speedometer drive gearbox are engaged with
the slots in the end of the hub barrel. Make sure also
that the speedometer drive gearbox is correctly
positioned so that there is no sudden bend in the
driving cable. Make sure that the closed end of the
spring link points in the direction of travel of the
chain. Replace the chain adjuster cams in their
original positions or, if necessary, turn each of them
the same number of notches to tension the chain and
maintain correct wheel alignment. Do not forget to
refit the brake rod and adjust the brake so that the
wheel turns freely while the brake is off, while at the
same time only a small travel of the brake pedal is
necessary to put the brake on.
3. Removal of Brake Shoes for Replacement,
Fitting New Linings, etc.
Remove the complete wheel as described above,
then remove the left hand spindle nut, chain adjuster
and distance collar, thus permitting the complete
brake cover plate with operating cam, pivot pin,
shoes and return springs to be lifted off the hub
spindle.
In the case of the 7 in. brake fitted to the "Meteor
700" and "500 Bullet" models, the brake shoes can
then be removed, after detaching the return springs.
In the case of the 6 in. brake fitted to the "500
Twin" and "350 Bullet" Models, unscrew the pivot
pin locknut and the operating lever nut, after which
the assembly of the brake shoes, return springs, pivot
pin and operating cam can be removed from the
cover plate by unscrewing the pivot pin and applying
light blows with a hammer and drift on the end of the
operating cam. The return springs can then be
unhooked from the spring posts in the brake shoes,
thus allowing the whole assembly to fall apart.
4. Replacing Brake Linings
Brake linings are supplied either in pairs ready
drilled complete with rivets, Part No. 37786BX (6 in.
shoes) or 37787BX (7 in. shoes), or ready fitted to
service replacement brake shoes, Part No. 38042 (6
in. shoes) or 38043 (7 in. shoes). When riveting
linings to shoes secure the two centre rivets first so as
to ensure that the lining lies flat against the shoe.
Standard linings are Ferodo MR41 which are drilled
to receive cheese headed rivets.
5. Removal of Hub Spindle and Bearings
To remove the hub spindle and bearings, having
already removed the brake cover plate assembly and
speedometer drive gearbox, lift out the felt washers
and distance pieces then hit one end of the spindle
with a copper hammer or mallet thus driving it out of
the hub, bringing one bearing with it and leaving the
other in position in the hub. Drive the bearing off the
spindle and insert the latter once more in the hub at
the end from which it was removed. Now drive the
spindle through the hub in the opposite direction,
when it will bring out the remaining bearing.
6. Hub Bearings
These are deep groove single row journal ball
bearings. The lighter bearings used in the "350
Bullet" and "500 Twin" hubs are 5/8 in. i/d by 1.9/16
in. o/d by 7/16 in. wide. The Skefko Part No. is
RLS5. Equivalent bearings of other makes are
Hoffmann LS7, Ransome and Marles LJ 5/8 in.,
Fischer LS7.
The heavier bearings used in the "Meteor 700"
and "500 Bullet" Models are 5/8 in. i/d by 1.13/16 in.
o/d by 5/8 in. wide. The Skefko Part No. is RMS5.
Equivalent bearings of other makes are Hoffmann
MS7, Ransome and Marles MJ5/8 in., Fischer MS7.
7. Fitting Limits for Bearings
The fit of the bearings in the hub barrel is
important. The bearings are locked on the spindle
between shoulders and the distance pieces, which in
turn are held up by the cover plate nuts. In order to
prevent endways pre-loading of the bearings it is
essential that there is a small clearance between the
inner edge of the outer race of the bearing and the
back of the recess in either end of the hub barrel. To
prevent any possibility of sideways movement of the
hub barrel on the bearings it is, therefore, necessary
for the bearings to be a tight fit in the barrel but this
fit must not be so tight as to close down the outer race
of the bearing and thus overload the balls. The
following are the manufacturing tolerances which
control the fit of the bearings. The figures for the
bearings themselves are for SKF bearings but other
manufacturers' tolerances are similar.
"350 Bullet" "Meteor 700"
and "500 Twin" and "500 Bullet"
Bearing o/d 1.5622/1 5617 in. 1 8122/1 8117 in.
Housing bore 1.5620/1.5615 in. 1.8115/1.8110in.
Bearing bore .6252/.6247 in. .6252/.6247 in.
Shaft diameter .6252/.6248 in. .6252/.6248 in.
8. Refitting Ball Bearings
To refit the bearings in the hub two hollow drifts
are required, as shown in Figs. 2 and 3. One bearing
is first fitted to one end of the spindle by means of
the hollow drift; the spindle and bearing are then
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