Royal Enfield 250 CLIPPER, Руководство по техническому обслуживанию мастерской

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ROYAL ENFIELD WORKSHOP MANUAL
PAGE 60
1. Description of Frame
The frame is built throughout of cold-drawn
weldless steel tubing with welded joints, liners
being fitted where necessary for extra strength.
The principal frame members are made of
chromemolybdenum alloy steel tubing, which
retains its strength and resistance to fatigue after
welding.
The swinging arm unit which forms the chain-
stays pivots on a stout steel tube, which is secured
to the main frame by a long bolt passing through
the pivot plates. No bushes are fitted, as the
cast-iron chainstay bearing housing and hardened
surface of the tube are together good bearing
metals. Hardened steel thrust washers are pro-
vided 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 sus-
pension.
Later swinging arm units are fitted with two
rubber bushes in the bearing housing. The inner
sleeves of these bushes extend inwards and butt
together. Washers are situated on either side of
the bearing housing and a long stud runs through
the centre, onto each end of which screws a large
nut from the outside of the frame.
2. Steering Head Races
The steering head races, 31302, are the same at
the top and bottom of the head lug, but the
bottom race is fitted with a pressed steel cover.
The races 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 and Replacement of Rear
Mudguard Unit
The rear mudguard, mudguard carrier and
dual-seat are removable in one unit after merely
slackening the two rear suspension top fixing nuts
and pushing back the bolts about
1
/
8
in. to release
their heads from the recesses on the inside of the
carrier brackets. Stand behind the machine, grasp
the lifting handles (if fitted) and pull the mud-
guard assembly upwards until the attachment
brackets are clear of their respective nuts. Now
pull backwards until the clip at the front of the
mudguard carrier is free from the backstay bridge
tube of the frame, when, after disconnecting the
rear light cable, the complete assembly can be
removed.
When replacing, engage the front clip first and
drop the assembly into position. When tightening
the nuts make sure that the heads of the bolts are
right home in the recesses on the inside of the
carrier attachment brackets.
4. Removal of Rear Suspension Unit
First remove the rear mudguard unit as des-
cribed above. Undo the rear suspension top pivot
pin nut and drive out the pivot pin. Then hinging
the suspension unit back on the lower pivot pin,
remove the lower nut and push the suspension
unit off the pivot pin welded to the fork end.
5. Servicing Rear Suspension Units
The Girling units fitted to this machine are
sealed, and servicing of the internal mechanism
can be carried out only by the manufacturers.
The bottom cup for the suspension spring is
adjustable in three positions, the necessary " C "
spanner will be found in the tool kit. The bottom
position is suitable for a medium-weight rider ;
the centre position for a heavy rider or a medium
weight rider and medium weight passenger ; and
the top position for a heavy weight rider and
heavy weight passenger. The adjustment raises the
rear end of the machine to compensate for extra
weight so that the normal riding position of the
suspension unit is always roughly midway
between the two extremes of travel.
The rubber bushes in the top and bottom eyes
can easily be renewed and the spring can be re-
moved 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 re-assembling, the
spring should be greased to prevent rust and
squeaking if it should come into contact with
either of the covers.
6. Removal of Swinging Arm Chainstays
First remove one of the pivot pin nuts and
pull the pivot pin out from the other end. To
release the pivot bearing it is necessary to spread
the rear portion of the frame, using the frame
expander, E.5431, which will spread the frame
sufficiently to enable the spigots on the thrust
washers to clear the recesses in the pivot plates
forming part of the frame.
With the later rubber bushed swinging arms,
remove one of the pivot pin nuts and withdraw
the pivot pin. The swinging arm can now be
removed without resort to the frame expander.
7. Centre Stand
To remove the centre stand, first remove the
footrests, footrest bar and distance tube. Remove
the two studs holding the small engine plates to
the engine-gear unit, disconnect one end of the
H6
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