1906-Curtiss-Twin_1

Known as the “Father of Naval Aviation” and “the fastest man alive” Glenn Hammond Curtiss was a pioneer motorcycle and aeronautic inventor.

This Curtiss uses a seven horsepower v-twin. It is a lightweight, powerful motor proven in dirigible aircraft. One feature unique to Curtiss at the time was the all-roller-bearing crankcase, for smoother and reliable running. This 1908 example features the unique extended rear frame and pillion saddle plus the passenger’s own handlebar to enable him or her to hold onto the bike, bicycle tandem style (but without the pedals.) Curtiss motorcycles are extremely rare and we are happy to have this example on display at the National Motorcycle Museum.

Glenn Curtiss was born in 1878 in Hammondsport, New York and within 20 years was running his own back room bicycle shop after very little formal education. In addition, he was a Western Union bicycle messenger and bicycle racer, and something of an inventor for Eastman Kodak. Of course his primary accomplishments were in aviation.
In 1902 he had set up the manufacture of his own motorcycle – a Hercules – using his own single-cylinder engine. In 1903 America’s first v-twin came from his shop. Motorcycle building started in 1904 and but ended in 1912. Rumor has it that his first carburetor had been built from a tomato soup can! In 1903 Curtiss set a motorcycle land speed record of 64 mph. In 1907 he captured an unofficial world motorcycle speed record of 136.36 mph using a 40-horsepower “airplane” V8 in a shaft driven motorcycle!

Specifications:

  • Engine – V-Twin, 38.5 cubic inches
  • Dimensions –  3.57 inch bore and 3.8 inch stroke
  • Specifications – Six horsepower at 1,500 rpm
  • Ignition – Battery and coil
  • Final drive – Non-slip belt drive
  • Wheelbase – 58 inches
  • Weight – 150 Pounds
  • Price – $275
5 replies
  1. gstril
    gstril says:

    you know a lot of us old guys understand that the engines from the early days of motorcycling were not strictly push rod operated as far as the valves go . I think you could educate and interest some of the younger enthusiasts by giving more technical descriptions of the other systems that were used like the atmospheric intake vale systems I have never actually seen a good description of how they worked.

    Reply
    • Neil Tillett
      Neil Tillett says:

      An atmospheric intake valve is simply a poppet valve with a very weak spring that keeps the valve closed for compression but allows vacuum to open the valve during the intake stroke of the piston.

      Reply
  2. howard
    howard says:

    The intake valve is opened by the low pressure created when the piston is on the intake stroke. That required very weak springs on intake valves limiting RPM. More horsepower need higher RPMs, cam operated valves

    Reply

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