Service manual
6
recommends that four grooves be ground on
each side of both front and rear connecting rods.
See Figure 3. Make these grooves .020" to
.030" deep and .030" to .040" wide and should
be ground 90° from each other. After making
grooves, remove all sharp edges and burrs with
emery cloth.
B. Thoroughly clean all parts to remove dirt,
filings, etc.
CAUTION - Burrs, dirt, filings, etc. left on connecting
rod components may circulate in oil damaging other
parts possibly causing engine failure.
8. Lower End Assembly (All)
NOTES
●
All current production S&S Evolution Sportster style
flywheels are made from closed die, heat treated, steel
forgings. They do not have connecting rod thrust
washers like earlier S&S or stock flywheels, because
present flywheel material is harder than thrust washers
previously used.
●
S&S Sportster V
2
style flywheels come with three
timing marks, "F", "R" and "TF". The "F" mark stands
for front cylinder 30
°
before top dead center (TDC).
The "R" mark is rear cylinder 30
°
before TDC, The
“TF” mark is TDC front cylinder . When "F" or "R" mark
is placed in center of timing hole it means that cylinder
is timed at 30
°
before TDC. We recommend that "big
inch" Sportster engines be timed at 30-32
°
before TDC
rather than the stock 40
°
before TDC. See
Performance Notes, "Ignition Timing".
●
Usually S&S flywheels are balanced before leaving
our facility. Some customers prefer to do their own
balancing or to have another balancing shop do the
work for them. This is acceptable in most cases.
However, we have had some bad experiences with
dynamically balanced flywheels that have forced us to
void our guarantee if flywheels have been balanced in
this fashion.
CAUTION - Flywheels assembled improperly prior to
being dynamically balanced may sustain irreversible
damage to mainshaft and crankpin tapers during
actual balancing. S&S voids its guarantee if flywheels
have been balanced in this fashion.
●
Many problems in assembling and truing flywheels
can be prevented by careful inspection of all parts used
in the assembly.
●
Cleaning parts prior to and during assembly and
keeping parts clean after final assembly are imperative to
minimize contaminants that may circulate in oil and
shorten engine life. Many parts can be cleaned with soap
and water first. Then, reclean all internal parts and gasket
mating surfaces using high quality solvent that does not
leave any harmful residues. Be sure to read and follow
manufacturer’s instruction label before use. Use drills
and compressed air to clean all oil passageways of dirt,
filings, etc. whenever possible. During actual final
assembly, recoat all internal parts with high quality engine
oil or assembly lube such as S&S #51-9000.
CAUTION - Manufacturing chips, dirt and/or other
contaminants circulating in engine oil may possibly
damage engine components resulting in shorter
engine life and possible engine failure.
WARNINGS
●●
●●
● Some solvents, degreasers, gasoline and other
chemicals are harmful to skin, eyes and other body
parts. Many items are flammable and present a fire
hazard. Read manufacturer’s instruction label for
proper use. Use in well ventilated area and wear
protective clothing when using them to avoid
personal injury.
●●
●●
● Compressed air and particles dislodged by
compressed air are harmful to eyes and body. Wear
protective goggles when using compressed air and
always direct air stream away from body parts such
as hands and eyes. Never direct compressed air
toward other people.
Perform following steps when assembling flywheels:
A. Thoroughly clean all parts to be used. This
includes mainshafts, main bearings, connecting
rods, rod bearings, keys and flywheels including
tapers and key ways.
CAUTION - Burrs, dirt, filings, etc. left on flywheel
assembly parts may circulate in oil damaging other
parts possibly causing engine failure.
B. Inspect key ways and oil holes in flywheels for
burrs and remove if necessary.
NOTE - S&S does not recommend lapping tapers to
remove burrs. This practice tends to distort the taper
by removing material unevenly around the
circumference. This makes flywheels difficult if not
impossible to true. In addition the lapping process work
hardens the surface of the taper. This hard surface
makes it very difficult to pull shaft or crankpin into taper.
If crankpin and shafts are not pulled fully into flywheel
tapers, excessive rod side play and assembly width
may result. Lapped flywheel tapers are also very
difficult to resurface if repairs are ever needed.
Figure 3
Grind four oil
grooves on both
sides of forked rod