Warning – S&S Cycle TWO THROAT Carburetor (Serial E1190 & Higher) User Manual

Page 4

Remember, however, the bowl overflow system is a
safety aid only, and does not mean you do not have to
turn off the fuel petcock. Always turn off the fuel
petcock when the engine is not running.

6. With the fuel line in place, the air cleaner backplate

and mounting bracket can be installed.

NOTE - Before installing the air cleaner backplate, Part
#17-0280, be sure any flash is removed from the formed
holes, especially the bowl vent hole which is positioned
between the air horns just below the middle top mounting
screw hole, and the small drain hole positioned near the
middle bottom of the backplate. The bowl vent hole
matches up with a hole in the carburetor body. If this hole
is blocked or restricted, the carburetor will not run properly.

The Sportster

model bracket bolts to the

front intake cam cage stud and to the front
die-cast hole in the air cleaner backplate.
The shovelhead bracket bolts to the hole in
the front rocker box cover just to the rear of
the front intake pushrod and the die cast hole
in the backplate which is positioned closer to
the front airhorn.

Before final tightening of the manifold clamps
and mounting bracket, visually check the
motorcycle from the front to insure the carburetor
is horizontal when the bike is held upright.

Immerse the foam portion of the air cleaner
element in a light weight engine oil and squeeze
out. Before final assembly of the air cleaner,
check the needle and seat for possible leakage.
Hold the motorcycle level and turn the fuel
petcock on. If gas does not leak out of the end of
the carburetor bowl overflow hose after 10
seconds, the element and air cleaner cover can
be installed. The chrome wire mesh screen must
be bent to a smooth curve and inserted in the
front of the air cleaner cover. If the needle and
seat do not hold, the bowl should be removed
and checked. See the "General Information"
section of these instructions for details.

7. Special instructions for engines equipped with

breather vent line to the air cleaner.

S&S

air cleaners have a special boss cast into

the air cleaner backplate designed especially
for this vent. The backplate should be drilled
and tapped for a

" pipe nipple. This can be

procured at most any hardware store. After the
air cleaner backplate modification is done, the
vent line should be secured with a clamp.

B. Starting Procedure

This carburetor has a conventional choke type starting
mechanism. It has a tension spring, Part #11-2144, that
constantly applies pressure against the choke lever,
Part #11-2246, so that it will remain in position once
set. The choke plates, Part #11-2273, are fully closed
when the lever is pulled up to the stop. The S&S Two-
Throat carburetor also has an accelerator pump which
will squirt a stream of fuel directly into each manifold
opening when the throttle is opened quickly.

Cold Starts

One may use the accelerator pump to prime a
cold engine rather than the full choke method.
Wait for 10 seconds after turning on the fuel
petcock and then prime the engine by giving
two quick wide open throttle movements. Then
kick with the choke in the

closed position

and the throttle slightly opened. But be careful
as it is easy to flood the engine with the
accelerator pump. If you think the engine is
flooded, open the throttle slowly to the wide
open position. By opening the throttle slowly
the pump is not actuated. Also open the choke
and then kick through until the engine starts or
the flooded condition is cleaned out.

During our extensive testing with this
carburetor, we eventually got to the point
where we rarely used the choke, normally
accomplishing most cold starts by priming with
the pump only.

Motors will react differently due to the type of
cams or pipes, etc. and you will have to
experiment with your particular bike until you
find the best starting procedure for your own
set of circumstances.

WARNING