S&S Cycle Big Twin Engines with 3-1/2 and 3-5/8 Bore Crankcases and Special Application (SA) 4 Bore Crankcases - Manual (Page 12)

PUSHROD INSTALLATION AND ADJUSTMENT (All
Shovel Style)
Shovelhead pushrod installation will be similar to procedures
described in Steps 1, 2 and 6 of preceding section, except
pushrods will be installed in pushrod tubes and inserted into
rocker boxes after O-rings or corks installed. Adjustment will
depend upon type and brand lifter used. Refer to Harley-
Davidson
® Service Manual and instructions provided by lifter
manufacturer. In some instances, S&S ® Pushrod Instruction Sheet
#51-1035 will prove helpful.
INSTALL INTAKE MANIFOLD
Install manifold as explained in Carburetor Installation and
Jetting Instruction Sheet #51-1012.
FINAL INSTALLATION
Finished engine should be installed in frame according to
authorized Harley-Davidson
® Service Manual. Clean gas and oil
tanks thoroughly before installing, and be sure all traces of
solvent are removed. Old oil lines should be flushed or replaced,
and a new oil filter installed. With engine installation complete,
carburetor and air cleaner assembly can be installed according to
Carburetor Instruction Sheet #51-1012.
IGNITION TIMING
S&S recommends using electronic ignition with adjustable
advance curve in Super Stock
® and Super Sidewinder ® engines.
Adjustable curve permits slowing rate of advance to control or
eliminate pinging under heavy load or when elevated
temperatures or poor quality gasoline encountered. Install
ignition according to manufacturer’s instructions. Leave spark
plugs out while static timing to ease flywheel rotation.
Flywheels in S&S big twin engines have three timing marks:
( I F ) = Front cylinder firing mark, 35˚ degrees before TDC
with vertical line in center of hole. See caution below.
(● ● R ) = Rear cylinder firing mark, 35˚ degrees before TDC
with dot in center of hole.
( T:F) = Front piston, Top Dead Center with colon (:) in center
of hole.
Most fully electronic ignitions are timed at TDC. Points and other
ignitions with mechanical advance are timed at front cylinder
firing mark. With correct mark centered in timing inspection
hole, ignition at full advance will occur 35˚ before TDC. S&S,
however, recommends setting initial timing at 32˚ BTDC.
This can be accomplished by setting the ignition to fire when
flywheel mark is leaving timing inspection hole on left side.
Operating big twin engine with mark centered in hole at 35˚ ∞
can cause detonation and damage to engine not covered
under warranty.
Additional minor adjustment of timing may be required due to
poor quality gasoline, extremely hot climate, etc., but ignition
should occur between 28˚ and 32˚ BTDC when fully advanced,
and engine closely monitored for heat build-up.
In general, excessive ignition advance will cause engine to kick
back against the starter during start-up and “buck” when ridden
at steady speed with partial throttle. An advanced condition can
also cause pinging or ignition knock and possible piston damage.
These symptoms may not be noticed if electronic ignition with
“soft” advance curve is used.
Excessive ignition retard causes sluggish performance and severe
overheating with possible subsequent damage to the engine,
and must also be avoided. Immediate or rapid exhaust pipe
discoloration is usually a sign of retarded ignition timing.
Pinging or ignition knock is an early sign of detonation and
possible impending engine damage. Should pinging occur,
the throttle must be backed off and the cause determined and
corrected. Excessive retard is less obvious but equally
destructive. For that reason, final timing should be confirmed
with a timing light or other accepted procedure.
LUBRICATION
S&S recommends the use of Mobil 1 VTwin 20W-50 synthetic oil
in our engines.
Perform following steps before starting engine:
1. Connect oil lines according to Harley-Davidson
® Service
Manual. Be sure clamps are tight and lines routed to avoid
kinks and hot surfaces such as exhaust pipes.
2. Place correct amount of oil in tank.
3. Remove any remaining air from oil pump.
Air trapped in oil pump can prevent oil from circulating
through engine, causing extensive damage to engine.
Oil on tires or brakes could cause loss of control of motorcycle
resulting in serious injury to operator and others. Inspect tires
and brakes to insure both are clean and free of oil prior to
operating motorcycle.
4. Oil pressure should be confirmed with a quality gauge.
Pressure varies at idle, but should be high enough to keep oil
pressure warning light off. Pressure at operating
temperature should be 12-35 PSI at highway speeds.
SPARK PLUGS
Install spark plugs with gap recommended by ignition
manufacturer. Typically, .035-.045” is recommended for electronic
ignitions, .022” for points. S&S has used the following sparkplugs
in big twin engines with good results: Autolite
® 4265, Champion ®
RN12YC, Harley-Davidson ® 5R6A, and NGK BPR 4ES. In general,
same sparkplugs work for shovelheads if equipped with S&S
shovelhead cylinder heads or 1975-1984 Harley-Davidson
®
cylinder heads designed for long reach plug.
12
CAUTION
CAUTION
CAUTION
WARNING