Royal Enfield CO, Руководство по техническому обслуживанию мастерской

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ROYAL ENFIELD 350cc O.H.V. WORKSHOP MANUAL
Page 27
bearings, place one finger across the head races just
beneath the ball head clip. The steering head should be
adjusted so as to have the minimum of play in it,
while, at the same time, the fork must swing easily to
either side when the handlebars are given a slight tap.
To adjust the head bearing, first unscrew the steering
damper knob, then loosen the nut on the pinch bolt
through the ball head clip (see Fig. 39), and adjust the
head bearing by means of the large nut on top of the
ball head clip. Remove as much play as possible
without interfering with the free movement of the
steering head.
Do not forget to tighten the pinch bolt
nut. This takes the strain off the threads in the top
adjusting nut and failure to tighten the pinch bolt may
cause the threads in the adjusting nut to strip, with
serious consequences.
49. Dismantling and Reassembling Steering Head.
To dismantle the steering head, take the weight
off the front of the machine by supporting the
crankcase on a suitable box, then remove the steering
damper knob and anchor bolt (see Fig. 39). Next
remove the head bearing adjusting nut, loosen the
pinch bolt nut (see Fig. 39) and drive the projecting
end of the steering stem through the ball head clip.
Lift the ball head clip away in a forward direction and
withdraw the front forks complete, with steering
stem, from the lower end of the head lug.
When replacing the steering stem and forks,
assemble the lower head race on to the steering stem
with clean grease round the balls. Note that there are
only 19 balls in each race. Do not attempt to fit an
extra ball. Insert the steering stem upwards through
the head lug, place the upper ball race in position and
knock the ball head clip down on to it, then screw
down the head bearing adjusting nut until the
adjustment is correct and lock up the pinch bolt nut.
50. Steering Damper.
If the steering is found to bind even when a little
play is present in the head bearing, the probability is
that the steering damper is not freeing properly. To
check this, remove the ¼ in. diameter bolt which
attaches the middle plate of the steering damper to the
head lug on the frame (see Fig. 39). This puts the
damper completely out of action and if the steering
now becomes free this is an indication that the damper
was previously binding. In order to ensure that the
damper frees properly, the middle plate and the
bottom plate must both be parallel with the turned
face on the bottom of the steering stem. To ensure
this, loosen the ¼ in. bolt securing the middle plate to
the head lug ; also the second ¼ in. bolt securing the
bottom plate to the steering stem. Both these pins pass
through slotted lugs on the plates and the plates can be
tapped up or down as required in order to bring them
parallel with the lower face of the steering stem. Lock
up the two ¼ in. bolts tightly, with the bottom and
middle plates and the steering damper in such a
position that the damper is perfectly free. Binding of
the damper causes bad steering at low speeds and it is
more important to ensure that the damper comes
perfectly free than for it to be capable of locking the
steering tightly. Damping of the steering of this
machine is required only at very high speeds or across
country and then only light damping is required.
CARBURETTOR
(AMAL Type 276 A.C./1A)
51. Adjusting Slow Running.
To set the carburettor so that the engine ticks over
slowly, proceed as follows:- Start up the engine and
set to run on a small throttle opening with the air fully
open and ignition about half retarded. Screw up the
throttle stop adjusting screw (see Fig. 40) until the
engine begins to speed up. Now close twist grip
completely and make sure that there is slack in the
control cable, if necessary adjusting by means of
screwed adjusting bush on top of the carburettor
mixing chamber. Next unscrew throttle stop adjusting
screw gradually until the engine is running as slowly
as possible consistent with steady, even firing. Next
adjust pilot air screw in or out until the engine speed is
its maximum for the given throttle and ignition
settings. If the speed is now too high, unscrew throttle
stop adjusting screw further and, if necessary, correct
adjustment of pilot air screw. When the best settings
have been found, lock up locknut on throttle stop
adjusting screw and screw up throttle cable adjusting
bush on top of mixing chamber until all but a little
slack is taken out of the control wire.
52. Dismantling Carburettor.
The construction of the carburettor is clearly
shown in Fig. 40. Carburettors should be dismantled
from time to time in order to clean out accumulations
of silt from the bottom of the float chamber, float
chamber holding bolt, etc. If it is necessary to remove
the jet block from the mixing chamber, great care
should be taken in doing this as the jet block is easily
distorted. When replacing the float make sure that the
spring clip engages correctly with the groove in the
fuel needle.
53. Causes of High Petrol Consumption.
If the petrol consumption is excessive, first look
for leaks either from the carburettor, petrol pipe,
petrol taps or tank. If coloured petrol is in use this will
readily indicate the presence of any small leaks which
otherwise might pass unnoticed. If the petrol system is
free from leaks, carefully set the pilot adjusting screw
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