Just before rolling out and leaving for Sturgis I check my
plugs in the only stock item left on the 93-inch House of
Horsepower/S&S hot rod Shovelhead—the early heads.
Unfortunately every time I attempted to unscrew the short reach
plugs the threads and heli-coil came with them. I rode to Sturgis
without ever checking the plugs again.
I reinserted the helicoils with the infamous green
race Loctite and didn’t touch them again. The bike ran like a
champ fortunately, but every time it hiccupped, I gulped with the
notion that the plug might need removing. Phil’s Speed Shop
rebuilt the heads with all the best components and Phil offered
to fix them, but I was on my way to the Badlands. No time. Plan
B was to replace the old stock heads with S&S Performance
updated heads upon return to the coast. Sounded good to me
and I started a Shovelhead improvement list:
1. Replace the heads.
2. Remove the front barrel and ream the oil return hole. (it
leaked from where the factory drill intersected holes for the oil
return passage from the top and the bottom of the barrel. We
plugged it with a brass wedge and JP Weld. It always bothered
3. Realign the Mikuni Carb for a better, more secure fit.
There’s a critical trick to this.
4. Replace the copper/hard oil lines with plain old rubber
Sure, there not as sexy, but I was running a rubbermounted oil
bag and solid mounted lines. Something was going to give. One
line cracked in Sturgis. It was time for a change.
We decided to try out stock oil line clamps.
5.Take the pipes off, have them bead blasted and treat them
with flat black heat paint.
We’re still waiting on one more heat shield.
6. Have the replacement heat shield powder coated. One
snapped off in Denver after a cannonball sized pothole kicked
I think that was the extent of it. Of course one fix often
leads to another. The first prep aspect was to hit Larry Settle’s
shop for Rocker gaskets, head gaskets and barrel gaskets. I
needed one barrel gasket to replace the front barrel gasket after
we removed it.
We disassembled the top motormount first and
carb, releasing it from the throttle cable and gas line and set it
aside. I discovered that my brass carb mount was cracked where
it met with the frame. I added a thick layer of braze.
We watched out for spilled gas. We removed the push rods
and kept them in order, because they were all different lengths.
We removed the pipes and tried to organize the fasteners so we
wouldn’t lose the bastards.
The above operations gave us space and accessibility to
reach the barrel nuts and head bolts. We discovered that both
fasteners had their quirks and why. Since this is a big bore
engine (3 5/8), the head bolts were a narrow 12-point stainless
steel jobs that were removed with 12-point 7/16 box end
wrenches. All my cool head bolt wrenches were too large for the
job. I discovered that it took every 7/16 box end wrench, in the
tool box, to reach all those 12-point heads. Ultimately I altered
a broken head-bolt wrench to reach in and find a secure
connection. We welded two Craftsman short 7/16, 12-point
sockets to the Snap-On head bolt wrench. Is that against the
code of the West, or what?
After MIG welding the sockets, grinding the welds,
smoothing the surfaces and polishing the edges, it worked like a
There’s another trick. The barrel bolts are also
and small, reachable with a ½-inch open-end wrench. In
they’re tall, so to remove them, the barrel must be lifted before
they will come completely off the case studs. Tricky.
There’s a trick about the oil lines that run to the rear head
and between the heads. I loosened up the pipe fittings, but then
let them sit. When the heads came loose so did the lines. We had
to watch this procedure when we slipped the heads back
together. I didn’t need to arch or bend the lines.
Once everything came apart we cleaned the gasket surfaces
thoroughly. We discovered that the blue tephlon gasket material
comes off with electrical contact cleaner better than trying to
scrap it, which I avoid. The catch with big cylinders is the slim
barrel gasket material and edges. Not much to work with
considering the additional power. Be extremely careful.
Here's the other oil feed line. It comes right out
with the heads removed. Don't bend it.
Before we go into the assembly process here’s the base
material from S&S about their heads and assorted equipment:
S&S SUPER STOCK® CYLINDER HEADS
FOR 1966-'84 SHOVELHEAD ENGINES
Super Stock replacement heads for 1966 to 1984
engines maintain a stock appearance for restoration purposes
but offer improved port shapes for riders interested in more
As with other S&S heads, our CNC machining maintains
dimensional accuracy and reduces cost. This allows us to
offer the finest possible parts at a reasonable price.
While stock heads use studs to attach the rocker box
assemblies, S&S heads utilize 5/16"-18 hex-head bolts.
Rocker cover bolts are included with each complete
Shovel-style head kit. Otherwise, S&S heads accept all
Note the fin in the intake. Also note the blown
head gasket. I’ll tell you about that later.
PORTS AND COMBUSTION CHAMBER
Intake and exhaust ports are in the stock locations and are
same size as stock. Stock intake manifolds and exhaust
are easily installed with no modification required. Heads
available for both the 1966-'78 o-ring and 1979-'84
Since S&S heads are compatible
stock manifolds, special manifolds are not required except for
engines with taller than stock cylinders.
S&S intake ports feature a directional vane to route
incoming fuel-air mixture around the valve guide and valve
stem for improved performance. At 1.940-inch, intake
the same diameter as stock, but exhaust valve
(1.720-inch) has been reduced by .030-inch to improve valve to
clearance for cams with high TDC lifts and to improve flow. A
stock-like hemispherical combustion chamber is compatible
with all standard Shovelhead style pistons.
VALVE TRAIN COMPONENTS
Valve train components used in S&S cylinder heads
Shovelhead engines are specifically selected for
under contemporary, real-life conditions. They are compatible
with present unleaded fuels. Valve springs can handle .
total lift. Heads are machined to accept cams with TDC lifts of
.210-inch on both valves.
Because S&S cylinder heads for Shovelhead engines
have stock dimensions, they readily bolt on with a
stock-like fit with no clearance problems with frames
and standard Shovelhead exhausts. Complete kits
include all gaskets required for installation except
intake manifold seals.
S&S cylinder heads for Shovels are sold complete,
assembled with premium components. Installed parts
include valve seats, guides, seals, valves, valve springs,
collars, and keepers. Complete kits also include rocker
cover gaskets, head and base gaskets, all required
hardware, and instructions.
We used the big bore head from S&S.
OPTIONS FOR SPECIAL ORDER
Cylinder heads for Shovelhead engines are available
from S&S in
black powdercoat as well as natural cast aluminum
Machining for dual spark plugs and/or external oil
return lines is
available at an extremely reasonable cost. Both of these options
normally associated with large-displacement, high-
competition engines. However, dual spark plugs are often used
street engines to control detonation or knock, and external
returns are not uncommon on high performance Shovelhead
engines. External oil returns are used to redirect return oil from
cylinder heads so that it does not drain into the flywheel cavity
the stock manner. This is intended to reduce drag on the
at high rpm. These options are available by special order only.
SPECIAL REPLACEMENT CYLINDER HEADS
FOR S&S 93-Inch HC SHOVELHEAD STYLE ENGINE
O-ring style 35/8" dual plugged – internal oil return
Set without valves and springs .......................90-1489
It was easy to clean the heads ‘cause Phil used thick brass
gaskets and they were unharmed, like a big brass washer. Here’s
where the quirky aspect jumped at us like a frightened cat. I had
my three grandkids hanging out over the weekend, and they
constantly asked me what they could do, so we positioned them
around the lift with little wrenches to tighten head bolts, a
Fortunately it was recommended not to use any gasket
sealer or glue with the Rev Tech tephlon coated gaskets. We
didn’t. The second tip was to align the O-ring heads with the
intake manifold before tightening. We also fed the oil lines into
place as we aligned the intake manifold and started the fittings,
but didn’t tighten them. Then the kids went to work. Then highly
educated Bikernet employees, like Snake, checked the head
While fitting up the carb, I made a new bracket
from the brace to the carb. It fit much better, and held the carb
more in line than the previous strap.
The next morning I asked Black Market John if the headbolts
were tight and received a positive response—I thought. That
afternoon, we blew both the head gaskets during our first road
After a one-block road test, the bike failed. It died and Kyle
discovered quickly that there was no compression. He pushed
the Shovel home.
That night we drank whiskey and I tore into the top end
once more. Fortunately we still had Phil’s copper gaskets and
they were good to go, as if they put a hex on the project.
The next day we hit the lift like hungry dogs determined to
remove and replace the heads pronto. All the other repairs were
made, so it was just a matter of stripping her down, replacing
the gaskets, bolting her back together and adjusting the valves.
Long shoreman Kyle Ross, tinkering with the oil line fittings
and almost shutting off the return line.
I discovered that adjusting the valves had it’s own tricks.
After we ran it a few miles I adjusted the solids by finding the
lowest spot in the cam travel and taking out all the play (one at a
time), but allowing me to spin the pushrods slightly. But then I
tightened the rocker boxes and had to adjust the valves again.
There she is, ready to fly once more.
Jessica said we could go for a ride now.