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Steam Power Restoration
Restoration of the Hubbard Steam-Powered Motorcycle

This project involves restoration of a rather rare breed of machine. Very few steam-powered motorcycles are known with the majority of historic "steamcycles" residing in museums (e.g., the "Field" steam motorcycle).  There has been very little commercial exploitation of applying steam power to two-wheeled vehicles, so most "steamcycles" that come to light are one-of-a-kind prototypes built by hobbyists and steam enthusiasts.  The steamcycle restored here is no exception. It was custom built by Arthur "Bud" Hubbard of Monroe, CT during the early 1970's.

  Powerplant left
The motorcycle frame is a 1956 Maico of East German manufacture.  The powerplant was hand built over about 4 years starting in 1969. 

A closeup of the handmade powerplant. This is the left side with most of the feedwater handling components. 

  right side
  pre restoration
Right side of the powerplant with most of the fuel handling components.  The steam engine has successfully run on compressed air since the restoration.

The steamcycle prior to restoration. It had been stored in a chicken coop for many years, and the ravages of time and oxidation are apparent.

Specifications of the Hubbard Steamcycle

  • Two cylinder, single acting steam engine
  • 3 cubic inch displacement for each cylinder (6 cu in total displacement)
  • Theoretical HP - ~6
  • Transmission - direct drive - roller chain
  • Boiler - triple coil - flash style - superheating loop
  • Operating pressure - 400-700 psi  superheated steam
  • Burner - vaporization style with throttle - alcohol preheating of vaporization coil
  • Fuel consumption - less than 1 gal per hour.
  • Fuel - originally designed for kerosene, also used gasoline
  • Water capacity - ~2 hours with planned condenser

Issues Remaining Prior to Operation Under Steam

  • Boiler was perforated due to rusting during storage.  Must be rebuilt.
  • During initial tests of the vaporization burner in the early 1970's, this key component never operated well on kerosene. Operation using gasoline was inconsistent and harzardous.
Another pre-restoration photo. The Hubbard steamcycle was purchased from Dick Greene. It is owned and restored by Jim Anderson.

The steamcycle engine will be demonstrated on compressed air at the Spring Power-UP on May 6, 2006.

Historical Note:

Mr. Hubbard built this steamcycle in the early 1970's.  He was however following a two-part article published in The Model Engineer and Electrician published in April of 1918!  This article is entitled A Design of a Steam Motor Cycle and was authored by Thomas Hindle.  The paper described in detail the construction of a steam motorcycle and included drawings and construction data. From a careful reading of the paper it is apparent that Hindle never actually built this motorcycle himself! It appears to be a paper exercise.  More than 50 years later, Bud Hubbard turned this design exercise in reality.   Therefore, all of the post-construction troubleshooting was left to Mr. Hubbard himself.  It is a testimony to the skills of Arthur "Bud" Hubbard that he 1) built this in the first place and 2) did extensive testing and improvements to his design to actually get it running on steam.  Mr. Hubbard kept a notebook that chronicled both the construction of the steamcycle and it's later testing and modifications.  His notes exemplify inventive spirit and clearly show the interative process involved in building anything mechanical. 

This page was prepared on 9/1/06 by Jim Anderson