Warning – S&S Cycle MGL Carburetor User Manual

Page 2

The S&S MGL series carburetor kit contains the
following items:

Carburetor
Intake manifold and bolts
Air cleaner w/mounting bracket
Fuel line w/two clamps
Two extra main jets
One tie strap

1. The old carburetor and manifold must be removed

and the manifold supplied with the kit installed. If
the carburetor is to be used on a knucklehead or
panhead, a bracket that goes from the center
crankcase stud to the bottom manifold bolt is
furnished. The bottom manifold bolt supplied is

”

longer (1

” overall length) and must be used in the

bottom hole only. The top manifold bolt is 1” long.
For installation on Sportster

models, a bracket is

furnished that goes from the front intake cam stud
to the air cleaner backplate. On shovelheads, a
bracket that goes from the front cylinder rocker box
cover to the backplate is used. Temporarily bolt the
carburetor in place.

2. An English type throttle must be used since the MGL

has a built-in throttle return spring. The stock
Harley-Davidson

throttle on 1974 and later models

can be adapted by soldering the last 1

” of inner

cable before cutting the ball or barrel fitting off the
end. The soldering is done to prevent the strands
from separating. Once this operation is done,
remove the carburetor and feed the cables through
the throttle cable boss on the carburetor body, the
soldered portion of the braided cable extending
into the throttle cable clamp on the throttle arm. A
little freeplay should be left in the throttle when
the screw on the throttle cable clamp is tightened.
Any excessive play can be adjusted out at the
throttle grip before engine start-up.

For those bikes that are not already equipped with
an English throttle, one can be purchased
separately. To install, remove the old throttle by
loosening the screw at the end of the handlebar.
Drive the ring the twistgrip is shouldered against
off the handlebar. Slip the furnished spacer on the
handlebar. If 1" handlebars are used, do not use
the spacer. Next, install the throttle assembly on
the handlebar and temporarily tighten in the
desired position. The throttle cable supplied is extra
long to compensate for different length
handlebars. Turn the handlebars to the extreme left
position so that the length of the cable needed can

be determined. Hold the throttle cable housing in
position at the throttle grip and at the throttle
cable boss on the carburetor and adjust to the
desired length. Cut the cable housing only. Install
the throttle cable into the throttle cable housing
and throttle grip and thread them through the boss
and throttle cable clamp. Note where the throttle
cable clamp comes on the cable. This portion
should be soldered to prevent the strands from
separating. Any additional cable must be cut off.
Lubricate the throttle assembly and cable during
the final installation. Leave a little freeplay in the
throttle when tightening the throttle cable clamp
screw so the throttle will close all the way. Any
excessive play can be adjusted out at the throttle
grip before engine start-up. Important: After all
cable adjustments are made, be sure that the
throttle works freely and returns to the fully
closed position when the throttle is released

Most English type throttles have a friction screw that
dampens the self-closing feature on these throttles.
When over-tightened, the throttle will not close to the
idle position when the hand is removed from the
throttle grip. Operation under this condition is not
recommended because of the possible hazard
involved when the engine will not stop automatically
in an emergency.

We do not recommend the use of quick or

turn

throttles. They are not only dangerous but also
adversely affect the throttling characteristics of the
carburetor.

3. After installing the throttle assembly, make certain

that the O-ring is in place at the end of the
carburetor and bolt the carburetor in place using
the allen head bolts provide.

NOTE: For installation in big twins, the stock wire fuel
line bracket should be used to position the fuel line
between the cylinders.

The S&S

MGL series carburetor has been designed for performance applications to be used on large displacement

Harley-Davidson

big twin and Sportster

models. We do not recommend using this carburetor on stock Sportster

models and 74’s. The carburetor has a fixed main jet, fixed intermediate jet and intermediate air bleed, and an
adjustable idle mixture screw. It is made in the 1

” throat size only. This carburetor has a conventional choke for

starting.

WARNING