Royal Enfield 500 TWIN 1949, Workshop Maintenance Manual

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ROYAL ENFIELD WORKSHOP MANUAL
After removal of the fork head the lamp
bracket tubes can be lifted straight off and
the springs can be withdrawn from the
upper end of the main tubes.
7. Removal of Main Tubes
To remove the main tubes first dismantle
the fork as described in paragraph 3 then
remove the facia panel fork head and lamp
bracket tubes as described in paragraph 6.
Now remove one nut from each of the fork
crown clamp studs, remove the studs and
separate the clamp sleeves with a drift of the
form shown in Fig. 4. Now knock the main
tubes out of the fork crown either upwards
or downwards as may be most convenient.
If the machine has been in an accident and
the tube is badly bent both above and below
the fork crown, it may be necessary to cut
through the tube with a hacksaw before it
can be withdrawn.
8. Reassembly of Parts
No difficulty should be experienced with
this. When refitting the main tube use the
lamp bracket tube as a guide to its correct
position in the fork crown. The small
shoulder some 1.1/2 in. from the upper end
of the tube should be 1/8 in. above the top
of the lamp bracket tube when the latter is
in position on the fork crown. With the
main tube in this position tighten the fork
crown clamp screws before fitting the facia
panel fork head.
The cover tube must be fitted in position
on the fork crown and the clamp sleeves
placed in position before the main tube is
fitted. To keep the clamp sleeves in position
it is convenient to insert a short piece of
tube or bar in the eye of the fork crown
before putting the cover tube in position.
The short piece of tube will be pushed out
when inserting the main tube. Before
tightening the nuts on the three fork head
clip bolts make sure that the bolt heads and
the sleeves are correctly positioned with the
cut-away portion engaging the main tube or
steering stem. Failure to do this may result
in a cracked fork head.
When refitting the oil seal or fitting a
new one great care must be exercised not to
damage the synthetic rubber lip which
forms the actual seal. If the seal has been
removed from the upper end of the main
tube and is refitted from this end a special
nose piece (Fig. 5) must be fitted over the
end of the tube to prevent the thread from
damaging the oil seal.
The spring stud is a tight fit in the hole at
the lower end of the bottom tube. Once the
stud has been entered in the hole push the
bottom tube up sharply against the spring
until two or three threads on the stud project
beneath the end of the bottom tube. Now fit
the nut and washer and pull the stud into
position by tightening the nut. If necessary
fit the nut first without the washer until
sufficient thread is projecting to enable the
washer to be fitted.
9. Lubrication
The lubrication of the fork bearings is
elected by the oil which forms the hydraulic
damping medium. All that is necessary is to
keep sufficient oil in the fork to ensure that
the top end of the bottom spring stud is
never uncovered even in the full rebound
position. The level of oil in the fork can be
gauged by removing the top plug screw and
inserting a long rod about 3/8 in. diameter.
If slightly tilted this will ledge against the
nut at the upper end of the bottom spring
stud and indicate the level of oil above the
stud. If the fork is empty to start with the
quantity required is approximately 7.1/2
fluid ounces in each leg. Recommended
grades of oil are Castolite, Mobiloil Arctic,
Essolube 20, B.P. Energol S.A.E. 20 and
Shell X-100 20/20 w.
Section J3 Page 4
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