S&S Cycle Throttle Shaft Bushing - Manual

S&S
®
Cycle, Inc
.
14025 Cty Hwy G PO Box 215
Viola, Wisconsin 54664
Phone: 608-627-1497 • Fax: 608-627-1488
Technical Service Phone: 608-627-TECH (8324)
Technical Service Email: [email protected]
Website: www.sscycle.com
Instruction 51-1009
12-04-13
Copyright © 1986, 1993, 2006,
2013
by S&S® Cycle, Inc.
All rights reserved.
Printed in the U.S.A.
Installation Instructions: Throttle Shaft Bushing
All S&S® Carburetors Except E & G Series Super and Two-Throat
Two methods of repair are given to restore
carburetor throttle shaft holes. The degree of
wear determines which method to use. Carb
bodies with extreme wear will generally have
elongated holes. This makes it impossible to
enlarge the hole as described in the Minimal
Wear Method and expect to have the hole
located in the correct position. Therefore it is
advisable to use the Extreme Wear Method
if there is any doubt. If the Extreme Wear
Method cannot be used, return the carb body
to S&S® for restoration.
Carb bodies with minimal wear:
NOTE: Repair work for carbs with minimal wear
can be done using a drill press.
1. Using machinist’s vise or 90˚ angle plate,
clamp carb body so that both throttle shalt
holes can be drilled from same side of body.
On Super carbs make bowl gasket surface
parallel with drill. All early style and L Series
S&S carbs must have bowl gasket surfaces
lined up 90˚ to drill plane (perpendicular to
drill).
2. For all carburetors use “N" letter drill (.302"
diameter). Drill must be long enough so
that when it is inserted in drill chuck both
throttle shaft holes can be drilled in one
operation from same side of carb body.
3. Line up throttle shaft hole by centering on
drill point.
4. Carefully drill out throttle shaft holes.
5. Without removing carb from clamps ream
drilled throttle shaft holes with 5⁄16" (.3125")
diameter reamer. Reamer must be long
enough to ream both throttle shaft holes in
one operation from same side of carb body.
6. Deburr both holes.
7. Bushing has .314" diameter O.D. x .050" long
lead on one end. Start bushing with this end
and press to within .005" of carburetor bore.
NOTE: When correctly installed, bushing will not
be flush with the out side of throttle shaft boss. If
bushing is not pressed in far enough, air will leak
past throttle plate causing erratic carburetor
operation.
8. Ream throttle shaft bushings with .251"
diameter reamer. Ream both throttle shaft
bushings in one operation from the same
side of carb body. This insures that bushing
bores are correctly aligned and that throttle
shaft has correct clearance when installed
in bushing.
NOTE: For all drilling and reaming operations
the use of coolant or lubricant on tool is
recommended to insure a clean cut and a
straight hole.
CAUTION
If reaming operation is not performed
throttle shaft may bind and stick due to
misalign ment or improper clearance.
WARNING
If throttle inadvertently sticks in open
position, loss of control of motorcycle and
personal injury to you or others may result.
9. Thoroughly clean carb and re assem-
ble with new parts, making sure to install
throttle plate with beveled surface sealed
against carb bore.
Carb bodies with extreme wear:
NOTE: Repair work for carbs with extreme
wear must be done using a milling machine.
1. Use machinist’s vise or 90˚ angle plate
to hold carb body and bolt to mill table.
Super carb bowl gasket surfaces must
be lined up 90˚ to table while all early
S&S® carb bowl gasket surfaces must
be parallel to table. Use dial indicator to
check this if necessary.
2. Position and clamp assembly so that
throttle shaft hole is directly below chuck.
All early style and L Series carbs have
throttle shaft hole locations as illustrated.
3. Use 5⁄16" (.3125") endmill cutter with flutes
longer than depth of hole to be cut. Slowly
feed cutter when making new hole.
4. ushing has .314" diameter O.D. x .050"
long lead on one end. Start bushing
with this end and press to within .005" of
carburetor bore.
NOTE: When correctly installed, bushing will
not be flush with the out side of throttle shaft
boss. If bushing is not pressed in far enough,
air will leak past throttle plate causing erratic
carburetor operation.
5. Repeat steps 1 through 4 for opposite
throttle shaft hole.
6. Ream both throttle shaft bushings with
.251" diameter reamer. Ream both throttle
shaft bushings from the same side of carb
body. This insures that bushing bores are
correctly aligned and that throttle shaft
has correct clearance when installed in
bushing.
NOTE: For all drilling and reaming operations
the use of coolant or lubricant on tool is
recommended to insure a clean cut and a
straight hole.
CAUTION
If reaming operation is not performed
throttle shaft may bind and stick due to
misalignment or improper clearance.
WARNING
If throttle inadvertently sticks in open
position, loss of control of motorcycle
and personal injury to you or others may
result.
7. Thoroughly clean carb and reassemble
with new parts, making sure to install
throttle plate with beveled surface sealed
against carb bore.
All Supers except E & G Series carbs
Early Style & L Series Carbs
1 3/4" or 1 7⁄8" 1 7⁄8" or 2 1/4"
1/2" throat bore 1/2" throat bore