S&S Cycle General Flywheel - Manual (Page 7)

Checking Connecting Rod Straightness
A.
Insert checking pin into wristpin hole. Place strips of paper
between checking pin and crankcase cylinder gasket surface
and apply slight downward pressure to wristpin end of rod
by rotating flywheels. Pull papers out slowly. Drag on papers
should be equal.
B. Rotate flywheels in opposite direction until checking pin
contacts cylinder gasket surface again. Repeat procedure to
rod again. If drag on papers is equal no bending is required.
If one paper is loose, use rod bending tool to tweak rod in
direction of loose paper and recheck. See Picture 6.
C. Repeat checking and bending procedure for other rod.
Picture 6
Big twin stroke codes
Code Stroke
1 4- 3 ⁄
8
"
2 4- 1 ⁄
2
"
3 4- 3 ⁄
8
"
4 5"
5 4- 1 ⁄
4
" (Stock 80")
6 4- 5 ⁄
8
"
12 5 1 ⁄
4
"
13 3- 1 ⁄
2
" (Stock 61")
14 3- 31 ⁄
32
" (Stock 74")
16 5- 1 ⁄
8
"
Four cam stroke codes
Code Stroke
1 4- 1 ⁄
16
"
2 4- 3 ⁄
16
"
3 4- 5 ⁄
16
"
4 4- 7 ⁄
16
"
6 4- 5 ⁄
8
"
7 4- 13 ⁄
16
"
8 5"
11 4- 1 ⁄
2
"
12 5- 1 ⁄
4
"
15 3- 13 ⁄
16
" (Stock)
16 5- 1 ⁄
8
"
Big twin engine style codes
Code Stroke
E 1936-1954
L 1955-1971
AL 1972-Early 1981
SE* 1955-Early 1981
BL Late 1981-Up
SL* Late 1981-Up
J
Early Delkron
4 cam cases
JL
Late Delkron
4 cam cases
H
Early McClure
4 cam cases
HL
Late McClure
4 cam cases
Four cam style codes
Code Stroke
None 1957-1976
B 1957-Early 1981
SB* 1957-Early 1981
BD† 1977-Early 1981
SBD*† 1977-Early 1981
C Late 1981-1985
SC* Late 1981-1985
SCD*† Late 1981-1985
SCDR*†‡ Late 1981-1985
D§ 1986-Up
DRS§†‡ 1986-Up
* Flywheels machined for special S&S sprocket shaft and stock pinion shaft.
§ Flywheels machined for special S&S pinion and sprocket shafts.
† Flywheel machined to use either 1977 to 1986 style Torrington main bearing or 1987 and later style caged roller pinion shaft main
bearing assembly.
‡ Machined for use with 1986 and later stock xl connecting rod bearings.
FLYWHEEL IDENTIFICATION
Style, stroke, and diameter of S&S ® flywheels can be determined by examining the serial number which is stamped on the
rim of both flywheels in the set. Usually the flywheel serial number can be read through the timing plug hole of an
assembled engine. Press-together flywheel serial numbers are stamped on the inside rim of S&S flywheels. A cylinder
must be removed in order to read serial number.
Year of Serial Flywheel Engine Flywheel
Manufacture Number Stroke Style Diameter
S S 1 1 2 2 3 3 4 4 -- 3 3 S S L L X X
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