Formed in the 1880’s in Fitchburg, Massachusetts, Iver Johnson Company built bicycles, firearms and by 1911, motorcycles. Not satisfied to follow other makers, stating a goal of “mechanical perfection,” innovative design and manufacturing techniques show in their motorcycles including this single-speed 1915 twin.
While a visit to the Museum would allow you to kneel next to this machine, feast your eyes on the Iver Johnson’s great details, we hope these photos will help. To begin with, the overall lines of the bike are unique. Iver Johnson used on some of their bicycles the “truss bridge” frame design, and used it on motorcycles as well. The sweeping fuel tank form is complimented by the rakish handle bar, a deep V form when viewed from above. Following the line of the handle bar, the leading link “girder” fork incorporates a delicate multi-leaf spring, nickel plated as are many detail parts on the Iver Johnson.
Hidden inside the gleaming nickel plated motor is a unique planetary gear driven “cam” to open and close the valves. An original factory drawing is included here to explain. Roller tappets ride on the outer surface of the large gear, so no actual “camshaft” is used. Also inside the engine, unique for the time, is a double pin crankshaft. Iver Johnson engineers felt that for optimal balance and smoothness the pistons should reach the tops of their cylinders simultaneously. Also, the engine served as a “stressed member” as the frame is open at the bottom. (For the two-speed V-Twin versions, a unique in-unit planetary gear setup was employed. But in use this transmission could not withstand the engine’s power. The company switched to a sourced two-speed rear hub arrangement for their two-speed twins.)
Patrick Simmons, singer and guitar player for the Doobie Brothers, was lucky enough to be high bidder at the E.J. Cole auction in 2015, and has this to say about his Iver Johnson; “I have always loved the design of these motorcycles, from the shape of the gas tank and frame, beautiful fork castings, well crafted leading link/leaf spring suspension, and most interesting, the offset crank pin design, which as far as I know, is the only example of this technology in this pre-World War I era. The gray, black, and white paint scheme, with the gold, and red lettering has so much aesthetic appeal for me personally. And the beautifully nickeled motor and quality mechanical castings make this one of the most beautiful motorcycles ever made.” Our thanks to Pat for offering his Iver Johnson on loan to the Museum for visitors to enjoy. With only a few still in existence it’s a real treat to see one.
- Engine: Side-Valve V-Twin
- Displacement: 62 Cubic Inch/1020cc’s
- Ignition: Magneto
- Horsepower: 7.5
- Valve Actuation: Planetary Gear Driven Cam
- Starting: Pedal Crank/Valve Lifter
- Primary: Direct to Clutch
- Transmission: Single Speed/Clutch
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What a beautiful motorcycle!! Amazing how we could have made this in American in 1915. Shows the indigenous engineering talent of this country back then.
Also, thrilled to see Mr. Pat Simmons (rock icon) has taken ownership of this beauty. It’s clearly in loving hands now.
Glad I logged in this morning.
I can only imagine walking into a shop that had one of these on display. Travel was by horses, or train. and likely only a small percentage of the townspeople had an automobile. And the airplane was not much more than cloth covered wood framed experiment.
It has been wonderfully and carefully restored which allows us to apreciate it as it would have been in the day! History! Art work! Engineering and transportation! Thank you Mr. Pat Simmons for your stewardship of this iconic piece of history!
Have a great Holiday Season!
This is a jewel of engineering. A beautiful motorcycle that I would be proud to display inside my home!
What a beautiful piece of history!! I hope Pat Simmons, along with showcasing this fantastic machine, takes it out and enjoys the wind in his face
astride this remarkable example of outstanding craftsmanship.
really appreciate not only this motorcycle, but others as well, well written stories along with awesome pics, keep up the great work, forever a fan dennis kranes north ridgeville ohio
Potato sound of the H-D. The cam drive is also very unique and I wonder how the cam dynamics are and can they be altered? The designers from years ago were still very capable. WWR