1912 SEARS
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.
1912 Sears DreadnaughtThis 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. 
Fuel priming pumpThe 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.
Positive chain drive.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.
Durable but elegant.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.
Engines made by Spacke were very reliable.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.
A mechanical work of art.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.
Leading links of front suspension.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.
Single unit cylinder castings.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.
The Schebler carburetor.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.
Where is all the noise coming from?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.


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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
Copyright 1999 Tazbat Publishing

Most recent update 03.07.2004



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