De Luxe
Dreadnaught Twin
| In 1912, Sears
Roebuck and
Company engaged the other Excelsior Company of N. Sangamon Street,
Chicago,
(not the same as owned by Ignaz Schwinn, Excelsior Motor Mfg. and
Supply
Co. and producer of Excelsior Motorcycles) to produce motorcycles
bearing
their name. This motorcycle although built down to a $237.00 price tag,
retained all of the current advancements of the higher priced
competition.
It had a Schebler carburetor, Eclipse clutch and counter-shaft,
positive
chain drive to the rear wheel and a Spacke made 70 cubic inch
engine.
Sears did not participate in motorcycle competitions to promote their
machines
as was the custom of all major manufacturers. Instead, they had top
name
components that were competition proven incorporated into these
motorcycles.
Evidently, the money Sears saved by staying out of competition was
passed
on in their low pricing. Sears had the advantage of their
nationwide
reputation in catalog sales to help promote these machines.
In 1916 Sears discontinued marketing motorcycles bearing their name. Right now the reason is unknown. The motorcycle you see in the following pictures was wrecked in an accident with a Franklin automobile. In the hands of its third owner it was caringly brought back to its original glory. The motorcycle originally came from Willimantic, Connecticut. |
|
Click on the photos to enlarge. |
 This
machine, for the money, was the equal of its contemporaries. With
a sprung front suspension, hand operated eclipse clutch, sprung saddle,
heavy duty loop frame, and 70 cubic inch vee twin cylinder 9 h.p.
engine,
it was a durable but elegant machine. For the price of most
single
cylinder motorcycles of 1912, you could buy this twin from Sears.
Sears also offered a 7 h.p. 61 cubic inch displacement model which
looked
the same, named the Sears De luxe Invincible Twin. |
 The
tank is actually two tanks in one. The tank you see holds two
gallons
of gasoline. What the owner is holding is a priming pump built
into
the fuel cap. Since the carburetor has no choke, this pump is
used
to manually inject a small amount of gas directly into the intake
manifold.
A smaller internal tank contains about one half gallon of lubrication
oil.
The aft cap is for filling the oil tank and has a built in manual oil
pump.
The engine oils of this era were generally 70 weight. |
 The
rear hub is a single speed unit manufactured by Musselman. It
also
contains the coaster brake. There were no front brakes in the
early
history of motorcycles. A two speed planetary hub was offered as
an option. The two speed hub was also offered by many competitors
such as, Harley-Davidson, Indian, Theim, and Thor. It was the
predecessor
of the sliding gear transmission. Sears also offered a lace on,
steel
studded, leather anti skid tire sleeve for extra traction on slippery
surfaces.
It cost $1.30. An optional add-on lighting package of the carbide
generator type cost $9.50. |
 The
chain on this side is used for starting the engine and operating the
coaster
brake. The steel strap at the back of the rear fender is what
holds
the stand out of the way when riding. The right handle bar grip
is
used to operate the throttle. The left advances and retards the
ignition
spark. At full retard it also activates the compression release
for
starting the engine. |
 F.
W. Spacke Machine Company, located on the 500 block of Madison Avenue
in
Indianapolis, Indiana manufactured quality engines for motorcycles and
other applications. This engine has a complete roller bearing
crankshaft.
This reduces friction, improves performance and reliability. This
engine
apparently was number 8,864 off their assembly line. With a bore
of 3.50 inches and stroke of 3.67 inches, it has a 70 cubic inch or
1157
cubic centimeter displacement. Serious prototype work on large
displacement
twin cylinder engines began about 1910 among all the big motorcycle
manufacturers.
Only two years after this prototype stage you see here an engineering
masterpiece. |
 When
I look at this engine (as well as other makes) I see a work of
art.
Sure it may be crude by today's standards but this and its
contemporaries
are what paved the engineering highways for today's modern super
bikes.
Notice the cable coming down the front bar of the frame. It
operates
a lever on which is attached a near horizontal rod. This rod
connects
to another lever on the side casing of the engine, just above the cam
housing.
This is the compression release, operated by the left handle bar
grip.
The compression was relieved for starting, simply by lifting the
exhaust
valves off their seats. By means of a shaft on the frame, the
same
cable operates the ignition retard and advance rod. You can see
the
rod on the opposite side of the frame. Near the bottom of the
engine
side case is a sight glass for checking the engine oil level. On
top of the intake valve rocker boxes, over the intake pipes, are two
knurled
thumb screws. To start a cold engine, these screws are
temporarily
removed to allow injecting fuel into the manifold. This Schebler
carburetor didn't have a choke. |
 Roads
and streets in 1912 were bad by today's standards. They were
unpaved
and often filled with holes and ruts. In the city you could have
cobble stone streets with trolley rails to negotiate. Without a
front
suspension, the ride would be bone jarring and damaging to the
machine.
Many early motorcycles would literally disintegrate in less than a
hundred
miles. This often was due to poor construction and design but
accelerated
by a lack of front suspension. Notice the lubrication cup for the
pivot point on the far axle link. |
 The
majority of motorcycles of this period did not use as much nickel
plating
as did Sears. Notice the back of the carburetor between the
cylinders.
The spark plugs, located beneath the intake manifold were manufactured
by, 'Splitdorf,' and cost 85 cents. The valve chamber, which is
an
integral part of the cylinder casting, houses both intake valve (on
top)
and exhaust valve (on bottom), making this an IOE (intake over exhaust
valve) engine. The rod running up the cylinder operates the
intake
valve. Beneath the valve chamber you see the spring which closes
the exhaust valve. |
 Under
the tank, to the left of the clutch lever, is the fuel petcock valve
and
its pipe leading to the carb. The carburetor was manufactured by
Schebler a dominant name at this period of history. If you had to
replace this carburetor, in 1912 it cost $8.55. At the back end
of
the tank is the oil petcock with a drip sight glass for metering the
flow.
This engine is completely lubricated by means of this method. It
does not have an oil pump. Because engines of this period burned
lots of oil, it was necessary at times to give a few extra strokes on
the
hand pump. On the seat post is a lever and rod. This is
used
to operate the exhaust cutout valve. |
 Under
the engine and incorporated into the muffler is the cutout valve.
This would be opened on country roads to give a little extra power to
the
engine, or just to make a lot of noise. |
Any comments on content
accuracy
or submissions
of additional information are
welcomed.
send email to
Ancient Alley
Thanks to: The Owner
and
The Illustrated Encyclopedia
of Motorcycles, edited
by Erwin Tragatsch
and
Inside American Motorcycling
by Harry V. Sucher
| Everything
in this section is copyrighted and protected by U.S. and International
Laws. Nothing may be copied, printed, etc. without written permission
from
Tazbat Publishing, a division of SJR Systems. For permissions contact
the Publisher
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