S&S Cycle Connecting Rods - Manual (Page 3)

Rod Side Play - Recommended rod side play is .015" to .035". If
on assembly, side play is found to be less than .015", surface
grind equal amounts off thrust faces on both sides of female
rod. The recommended bearing cage width is .008" to .020" less
than the female rod width. This must be checked if female rod
has been narrowed.
Rod to Rod Clearance - S&S ® rods have been machined to fit
stroker flywheels up to and including 5" stroke without
additional rod to rod clearance. If a longer stroke is to be used,
this clearance must be checked and increased as necessary - .060"
clearance is recommended and must be removed from the point
of contact on the female rod. Remove only enough material to
obtain recommended clearance. Smooth blend all clearance
contours to avoid stress risers.
Roller Bearing Clearance - S&S rods for street applications have
been honed to .001-.0012" running clearance. These rods require
a new engine break-in period of at least 2000 miles.
NOTE: If connecting rods are to be used in a racing application
where proper engine break-in is not possible, rod bearing races
must be honed to provide a minimum of .0005" additional roller
bearing clearance. S&S can supply rod sets with racing clearance
on request at no additional charge.
SPECIFICATIONS AND RECOMMENDATIONS
Centerline Measurement - All S&S rod sets except 34-7800 and
34-7900 measure 7.440" from wristpin centerline to crankpin
centerline. This dimension is the same as that of stock big twin
rods from 1974 to present and stock Harley-Davidson
® Ironhead
Sportster ® model rods from 1957 to 1985. This is .030" less than
stock 1936 to 1973 big twin rods. S&S big twin rods can be used
in applications replacing earlier, longer stock rods with the most
noticeable effect being a drop in compression of about
1 ⁄
3
to 1 ⁄
2
point. Piston to piston and piston to flywheel clearances should
be checked.
Rod set 34-7800 measures 6.926" from centerline to centerline.
These rods are the same length as stock 1983 XR-1000
® and
1986 and later Sportster ® model rods. Rod set 34-7900
measures 7.113" from centerline to centerline and are a special
length designed exclusively for S&S four cam
Sidewinder
® /stroker applications.
Wristpin Bushings - Connecting rods for Evolution ® engines
are sized for .792" diameter wrist pins. Connecting rods for
pre-1984 engines are sized for .791" diameter wrist pins.
Refer to Chart 1 for part numbers, applications, and wrist pin
diameters. When the correct style wristpin is used a running
clearance is .001".
NOTE: If connecting rods fit for Evolution ® wristpins are used
with pre-1984 style wristpins, running clearance will be .002".
Our experience has been that this amount of clearance will not
cause problems, however correct clearance should provide better
engine life and less possibility of noise.
S&S racing connecting rods utilize a 0.892” diameter wristpin.
Refer to Chart 1 for applications and part numbers. To alter a
bushed S&S rod set to be used with S&S racing pistons which are
equipped with a 0.892” diameter wristpins, the wristpin
bushing must be pressed out, and a
3 ⁄
32
” diameter hole drilled on
each side of the I-beam into the pin boss as close to parallel
with the I-beam as possible. See Figure 1. After these holes are
drilled, the wristpin hole of each rod must be honed to provide
0.001” running clearance.
3
Part # Application
Rod Wrist Pin Bearing
Length Diameter Cage Type
34-7000 1941-'81 bt 7.440" .791" Alloy
34-7003 1936-'52 61" bt 7.440" .791" Iron
34-7004 1941-'81 bt 7.440" .791" Iron
34-7010 1981-'84 bt 7.440" .791" Alloy
34-7011 1981-'84 bt 7.440" .791" Iron
34-7012 1984-Up bt 7.440" .792" Alloy
34-7013 1984-Up bt 7.440" .792" Iron
34-7200 1941-'81 bt 7.440" .791" Alloy
34-7203 1941-'81 bt 7.440" .892" Iron
34-7206 1941-'81 bt 7.440" .791" Iron
34-7210 1981-'84 bt 7.440" .791" Alloy
34-7211 1981-Up bt 7.440" .892" Iron
34-7212 1981-'84 bt 7.440" .791" Iron
34-7213 1984-Up bt 7.440" .792" Alloy
34-7214 1984-Up bt 7.440" .792" Iron
34-7500 1957-'81 xl 7.440" .791" Alloy
34-7510 1981-'85 xl 7.440" .791" Alloy
34-7700 1957-'81 xl BB 7.440" .791" Alloy
34-7703 1957-'81 xl BB 7.440" .892" Alloy
34-7710 1957-'81 xl SB 7.440" .791" Alloy
34-7720 1981-'85 xl BB 7.440" .791" Alloy
34-7721 1981-'85 xl BB 7.440" .892" Alloy
34-7722 1986-Up BB 7.440" .792 Alloy
34-7730 1981-'85 xl SB 7.440" .791" Alloy
34-7800 1986-Up xl 6.926' .792" Alloy
34-7900 1986-Up xl (Spec.) 7.113" .792" Alloy
34-7903 1984-Up bt (Spec.) 7.113" .792" Alloy
F Fiig gu urre e 1 1
C Ch ha arrtt 1 1