Carburetter With Pilot Jet System; Two Designs - Royal Enfield G Workshop Maintenance Manual

ROYAL ENFIELD 350cc and 500cc O.H.V. WORKSHOP MANUAL
VARIOUS CARBURETTER SETTINGS POSSIBLE FOR 350 AND 500 OHV
MODEL
350 G Stub fitting
350 G Flange fitting
G deluxe/350 Clipper
500 J Stub fitting
500 J Stub fitting
500 J Flange fitting
500 J2 Flange fitting
500 J2 Flange fitting

CARBURETTER WITH PILOT JET SYSTEM

Showing air valve
and throttle closed
Your carburetter may be vertical, inclined or horizontal, but diagrammatically this view applies
to all models, the variation being in the attachment to the engine and of the float chamber.

TWO DESIGNS

Fig. 2 above is the sectioned view of the standard Amal carburetter as shown on sheet 1,
figure 1. This is the standard design where the primary air to the main jet and the pilot jet
system comes in jointly through the main air intake, see figure 3, sheet 3. The type
numbers are 274, 275. 276 and 289.
An alternative design is made where the primary air to the main jet comes in through four
visible ports around the base of the mixing chamber, and where also the air supply to the
pilot jet system is separate. The type numbers of these carburetters are 74, 75, 76, and 89.
These tuning instructions apply to both the above designs.
CARB
YEAR NUMBER DIAMETER
1945-46 276AC/1A
1946-54 276BL/1A
1955-57 276AC/1A
1946-50 276BM/1A
1946-48 276CB/1A
1946-54 276CT/1A
1949-55 276CZ/1A
1947-55 276DB/1A
CHOKE MAIN NEEDLE
JET JET
15/16" 130 106
15/16" 130 106
15/16" 130 106
15/16" 140 106
1" 150 106
1" 150 106
1
1 / " 170 106
16
1
1 / " 170 106
16
Types 274, 275, 276 and 289
The type numbers are found
on the engine connection
Fig 2.
THROTTLE
N E E D LE
VALVE
P O S IT IO N
3 4
3 4
3 4
3 4
3 4
3 4
2 4
2 4
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PILOT
0.037
0.037
0.037
0.031
0.031
0.031
0.031
0.031