Caution, Caution warning caution caution – S&S Worldwide Motorcycle Accessories User Manual

Page 12

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Assemble cylinder heads and bolt assemblies on
cylinders with head gaskets in place. Install
pushrods and adjust to simulate final assembly.

NOTE: If hydraulic lifters are used, pushrods should be adjusted
so that lifters are completely collapsed for this test. This will
insure that lifters do not collapse due to valve spring pressure,
and that full valve lift is achieved.

Turn engine over in normal direction of travel two
complete revolutions.

10. Remove cylinder heads and check thickness of putty

in valve pockets.

11. If clearance is sufficient, disassemble top end and

proceed to final assembly.

12. If less than .060" clearance in any area exists,

remove piston from engine and grind area until
proper clearance is achieved. Clean parts
thoroughly before reassembly.

NOTE: S&S

recommends at least .060" clearance between valve

and piston valve pocket recess. While .060 clearance is
recommended minimum, it is advisable to have more, if possible.

Insufficient clearance between piston and valves may cause
them to contact each other during operation resulting in
damage to piston and valve train components.

13. Final Assembly and Engine Installation

NOTE: 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.

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.

●

Some solvents, degreasers 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.

Spin each head bolt down on its respective stud to be
sure threads are clean and free of contamination.

Install cylinder base gaskets provided dry. Be sure
gaskets match cylinder base line-up dowels and oil
return passageways.

Install pistons, rings and wristpin clips per S&S piston
instruction sheet 51-1028.

Coat piston skirts with engine oil or assembly lube and
install cylinders.

Place O-ring seals over cylinder head alignment dowels.
Install head gaskets provided in kit dry.

NOTE: Care must be taken to use correct alignment dowel O-
rings with 1986 and later Sportster

models head gaskets. Head

gaskets supplied with S&S cylinder heads compress to about
.045" thick and require .070" diameter O-rings. Gaskets supplied
with SIDEWINDER

for stock heads compress to about .0625" and

require .0825" diameter O-rings.

Using thin O-rings with thick gaskets or thick O-rings with
thin gaskets may cause oil leaks or possible ruptured head
gaskets around line-up dowels due to incorrect O-ring
compression.

NOTE: All S&S cylinder head kits are supplied with .045" thick
head gaskets, because this clearance promotes better combustion
chamber turbulence and flame travel. When other cylinder
heads are used S&S supplies .0625" thick gaskets. Using thicker
head gaskets with S&S heads reduces design efficiency and
performance. If thinner head gaskets are used with other
cylinder heads, piston to head and valve to piston clearances
must be checked during assembly.

Insufficient clearance between piston domes and cylinder
heads or piston domes and valves will cause damage to
pistons, heads and/or valves.

Bolt heads on cylinders. Place one or two drops of oil on
threads of each head bolt just prior to final assembly to
reduce friction and insure accurate torque readings.
Tighten bolts in stages using crossing pattern. See Figure
6. If using S&S crankcases, torque bolts to 45-47 ft. lbs. in
four stages. If using stock crankcases, follow the same
bolt tightening sequence, but use stock three stage
procedure and torque values shown in Figure 6. If using
other aftermarket crankcases, contact the manufacturer
for recommended head bolt torque specifications.

NOTE: Light coating of oil on head bolt threads minimizes friction
so torque values are not distorted. It cannot be emphasized
enough how important it is to do these steps carefully.
Maintaining a good head gasket seal depends on it.

Improper torquing sequence and head bolt torque values may
cause head gasket failure. Excessive torque values may cause
studs to pull out of crankcase.

CAUTION

WARNING

CAUTION

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