Steam Engine Motorcycle – Hubbard Steamcycle

Hubbard Steamcycle

Hubbard Steamcycle engineSteam engines would seem to be a bit impractical as motorcycle powerplants go but they look so cool you just have to try. This particular steamcycle is being restored by Jim Anderson of CAMA, the Connecticut Antique Machinery Association. It was built in the early '70s by Arthur "Bud" Hubbard of Monroe, CT following a design from The Model Engineer and Electrician in an article published in 1918. The writer never actually built the bike but Bud thought it looked pretty interesting so he figured he would give it a try.

The steam engine itself is a two cylinder, 6 cubic inch single acting engine using a direct chain drive. The engine is mounted in a 1956 Maico frame. Jim says it's supposed to run for about 2 hours on one water fillup and uses about 1 gallon per hour of gasoline, though he hasn't actually had it running yet according to the website, a few details remain to be repaired.

Bikes like this may be impractical but if you like old machinery, you just have to smile. I like it a lot.

Link: CAMA

If you think steam engines are cool, check out our steam engine books


  1. todd says

    if it is reliable, what isn’t practical about it? The thing should scoot along pretty well, much like a scooter with a ton of torque. I think the only challenge is heating the water in an efficient manner.

  2. says

    I can already envision a cool frameset to build to put a steam engine in! Strange thing is via my experience with old Stanley Steamers, they are usually dead quiet. It would like a bicycle going down the road at high speed with literally no road noise…

  3. kneeslider says

    Todd, as you mention, heating the water, that’s the impractical part. The old phrase, “building up a head of steam” means a fair amount of preheating before you have any power available. Steam power is neat but you have to be patient.

  4. says

    Thanks for featuring my steamcycle on yout website. I have yet to get the time or funds to build a new flash boiler for this bike but I do demonstrate it to the public using compressed air in our museum in Kent, CT. I’ve even ridden it a short distance (to the end of my air hose). On 75 psi air, it will s-l-o-w-l-y accelerate. It was designed to run on 600 psi steam which would give it alot more zip I’m sure.

  5. Mark 42 says

    I wonder if you could produce instant steam the same way a vaporizer (the type you put in a sick person’s room) does – with a little salt and electrodes.

  6. says

    It says that the bike is impractical, I don’t see how. Its comfy, you get a break every 2 hours. I’d have one and I’m British where we pay the equivalent of $8 for 1 gallon of fuel.

  7. Duncan McHarg says

    Just quickly. Dobel flash steam cars(3l, 4cyl engine) stone cold to ready to run in about a minute. Don’t have to wait too long.
    (out of time)

  8. says

    Concerning the time needed to get up a head of steam…According to Bud Hubbard’s construction/testing notes, when everything was working right he was able to generate 400 psi of steam pressure in under 5 minutes with his flash coiled tubing boiler and a vaporization burner.

  9. Robert Bell says

    The reason for the impracticality is the efficiency. This is a single acting steam engine (less efficient than multiple acting engines) with only 100cc of displacement. Generally this should have excellent torque at start, but would probably have a top end only suitable for back streets. If you want practicality get a scooter. If you want awesome nostalgic tech and the pleasure of building something completely unique this is definately the way to go.
    Flash boilers also decrease start up time by limiting the percentage of the water heated and increaseing the heat exchange surface area. Think tea kettle (standard boiler) vs. pouring water into a coiled tube (flash boiler)

  10. says

    Jim Anderson, Keep up the efforts. How about trying a scot air pack at 2500 psi, and regulate it down to 600 psi. Make the steam engine part be an air compressor as was done on the Westinghouse steam air compressors for locomotives. Use and conserve as much heat as possible to maintain economy. Heat out the stack is just wasted fuel. A Dobel steam engine on a bike frame would sure be trick but far too powerful for but the most daring.The KISS principle still applies. Good Luck!

  11. says

    If you are interested, I added a link to a YouTube video of the steamcycle running on compressed air to the CAMA website. ( I have a friend who runs a scuba shop and he’s going to loan me a high pressure aluminum air tank. That way, I can shed the air hose and take a ride (after mud season).

  12. Johnbear says

    How a bout a siumple three-wheeler? i’m a double amp and standard two wheeler would be major difficuty for me. would like to do some serious cruising, and keep it simple: No too good with motors to begin with.
    BTW: military use of steam had evolved into multi-use of same steam: one piston to another, etc. to get most use of the heat and steam.
    Then the turbo steam engine came alone, then direct fuel to the engine came along, and the last use of turbo-prop steam engine is now part of the nuclear subs, and etc. power systems, heating water to steam and then to the turbo blades, and power plant(s). But this is soooo kewl!!!