S&S Cycle Super B Series Carburetor - Manual (Page 7)

Troubleshooting Tips - engine will not idle:
1. Improper idle mixture and/or engine rpm setting.
2. Intake manifold air leak.
3. Sticky timing automatic advance mechanism or other
ignition problem.
4. Foreign material in air and/or gas passageway in carb
causing flow restriction to idle/intermediate circuit. Clear
holes with forced air.
Do not use wires or drills to clear holes. If sizes are altered,
air/fuel ratios of idle and intermediate systems will be
changed resulting in poor performance and irreversible
damage to carburetor body and intermediate jet.
Compressed air and particles dislodged using compressed air
are harmful to eyes and body. Wear protective goggles when
using compressed air and always direct air stream away from
body parts such as hands and eyes and other people near you.
5. Enrichment device plunger not sealed causing excessively
rich mixture. Be sure device is fully disengaged (in down
position) allowing plunger to bottom out and seal
passageway. CURE: Lift and release plunger several times,
letting it “snap” to closed position to fully seat and seal
against carb body.
Intermediate System
Intermediate range is used most often under normal riding
conditions and begins right off idle and operates up to
approximately 3000-3500 rpm or 50 to 60 mph depending on
gearing. Therefore, close attention must be paid to jetting
intermediate range to achieve optimum performance and best
gas mileage. Intermediate jet, part #11-7100, is reached by
removing float bowl assembly (See Picture 2). Actual size of
intermediate jet installed in carburetor is indicated on tag
attached to carb and/or on printed label on carburetor packing
box. Keep this information handy for future reference.
1. Road test bike, being sure to ride it far enough to bring
engine and oil to normal operating temperature.
2. Re-check idle mixture adjustments to be sure settings are
correct with fully hot engine.
3. Check throttling characteristics by slowly rolling throttle
on after maintaining steady speed. This should be done
at several rpm levels or speeds of 30,40, and 50 mph. If
“popping” or “spitting” (backfiring) occurs in air cleaner,
this indicates lean condition and intermediate jet must
be changed to next larger size (size is stamped on end or
side of jet).
4. Change jet accordingly and repeat road test. Smallest
intermediate jet that eliminates this condition should
provide best gas mileage.
NOTES on Intermediate Jetting:
●
See “Notes on Intermediate and High Speed Jetting” at
end of “High Speed Circuit or Main Jet” section of
these instructions.
● Whenever intermediate jet change is made, idle mixture
screw must be readjusted.
● Gas mileage and throttling characteristics may also be
determined by personal riding habits. Snapping throttle
open in lower rpm ranges is inefficient and uneconomical
because intermediate system is bypassed. When
intermediate system is bypassed engine momentarily goes
lean (from lack of fuel from intermediate) then rich (from
excessive fuel from main). In effect, engine uses more fuel
than it should. Engine will respond better and be more
efficient if throttle is rolled on and intermediate has time to
properly engage.
High Speed Circuit or Main Jet
High speed circuit begins around 3000-3500 rpm or 55-60 mph
and operates to maximum attainable speed. Main jet, part #11-
7200, is reached by removing bowl plug, part #11-2090.
NOTE - S&S ® has special main jet tool, part #53-0452, which is
handy for changing main jets.
Size of metering hole in main jet in thousandths of an inch is
stamped on end of jet. Size of main jet installed in new
carburetor from S&S is indicated on tag attached to carb and/or
on printed label on carburetor packing box. Keep this
information handy for future reference.
7
CAUTION
WARNING
S&S ® Super B Jetting Chart
Engine
Displacement
Stock CH
Strokers
Stock Big Twin
Mild Strokers
Strokers 84” or
Larger
Idle Mixture
Screw Setting
1-1/4 to 1-3/4
turns
1-1/4 to 1-3/4
turns
1-1/4 to 1-3/4
turns
Intermediate
Jet
.265 to .032 .0295 to .033 .031 to .036
Main Jet .062 to .070 .068 to .076 .072 or larger
Picture 2
Main Jet
Intermediate
Jet