Description Of Frame; Steering Head Races; Removal Of Rear Suspension Unit; Servicing Rear Suspension Units - Royal Enfield 350 BULLET 1949 Workshop Maintenance Manual

ROYAL ENFIELD WORKSHOP MANUAL

1. Description of Frame

The frames used on the above models are
basically identical, with swinging arm rear
suspension, but there are some small differences
in the lugs for engine attachment, the method of
attachment of the pivot point for the swinging
arm and in the width between the brackets
supporting the upper ends of the rear suspension
units. For part numbers of frames see
appropriate spares lists.
The frame is built throughout of cold drawn
weldless steel tubing with brazed or welded
joints, liners being fitted where necessary for
extra strength. All the main frame members are
made of chromemolybdenum alloy steel tubing
which retains its strength and resistance to
fatigue after brazing or welding.
The swinging arm unit which forms the chain
stays is provided with large diameter phosphor
bronze bushes and pivots on a stout steel tube
which is secured to the main frame by a long
bolt passing through the pivot lugs. Hardened
steel thrust washers are provided to deal with
side thrust. The torsional rigidity of the
swinging arm unit helps to maintain the rear
wheel upright in the frame and thus relieves the
wheel spindle of bending stresses to which it is
subject with other types of rear suspension.

2. Steering Head Races

The steering head races, 34085, are the same
at the top and bottom of the head lug and are the
same for all models. They are easily removed by
knocking them out with a hammer and drift and
new races can be fitted either under a press or
by means of a hammer and a wooden drift.

3. Removal of Rear Suspension Unit

The rear suspension units are readily
removed by undoing the top pivot pin nut,
driving out the pivot pin, then hinging the
suspension unit back on the lower pivot pin,
removing the lower nut and pushing the
suspension unit off the pivot pin welded to the
fork end.

4. Servicing Rear Suspension Units

(a) Proprietary Units. The proprietary units
fitted to most 1954 and all 1955 models are
sealed and servicing of the internal mechanism
can be carried out only by the manufacturers.
The rubber bushes in the top and bottom eyes
can easily be renewed and the spring can be
removed by pushing down on the top spring
cover so as to release the split collar above it.
After removal of the split collar the top cover
and spring can be lifted off. When reassembling,
the spring should be greased to prevent rust and
Section H1 Page 2
squeaking if it should come into contact with
either of the covers.
The standard solo springs have a rate of 100-
105lb. per inch and it is not difficult to compress
these by hand. Heavier springs having a rate of
130lb. per inch are available which may require
the use of a spring compressor, as shown in Fig.
2.
(b) Royal Enfield Units. Mark 1. Enfield
rear suspension units, Part Number 34276 or
36451, are shown in Fig. 3. Units having Part
No. 34276 are fitted with springs of .252 in.
diameter wire (Part No. 34284) having a rating
of approximately 200lb per inch (when fitted on