The SteamPed in all her glory!
Steam project by Roger Ulsky
My SteamPed started life as a Motobecane Moped which I obtained in a non running condition but with all the parts intact. I eventually want to build a steam car and decided this would be a good way to get my feet "dry" with steam land vehicles.
Installed a bash valve on top of the original head--I kept the head as it had a mounting bracket on it.
* Put a 1/8" plate on top of the piston to activate the bash valve.
* Plugged up the original exhaust port outlet.
* Removed the magneto and installed a 1" x 6" cast iron flywheel.
* Drilled a hole in the bottom of the case to use as the exhaust outlet. The steam exhausts from the cylinder into the crankcase and then out the outlet. Lubrication of the bearings comes from the steam oil.
* Put a fixed sheave on it in place of the centrifugal clutch it originally had.
The boiler is constructed from 30' of 1/8" pipe. The individual tubes were made as the photo shows and then welded into grids which were stacked up to form the complete boiler. The thermocouple is welded to the pipe at the top in this picture and then the wire is led down through the nest.
The burner was made for me by Mike Cross and I added an electrode for starting it. It unfortunately needed to be quite long to get good mixing of the gas and air.
The boiler control system is electronic. The thermocouple is in the hottest part of the boiler and if the temp is above 500 F, the pump bypass is closed and water is pumped into the boiler inlet and also into the normalizer inlet through a .025" orifice. If the temp gets above 800F, the burner shuts off.
1:- I used the original gas tank as the water tank--it carries a gallon. I also put a filter on the outlet as it had quite a bit of rust in it.
2:- There is no throttle. Stopping is by turning off the power by a handlebar controlled switch and the very effective brakes.
3:- The engine typically runs at 3-4000 RPM on 150 psi, 500 F steam. The vibration is intense!
4:- I wanted a metered oil supply into the steam. The pump is constructed from standard plumbing fittings and is driven by a small gearmotor so that it will deliver twice the amount of oil that the original Moped used.
5:- The feed pump is built up of standard plumbing parts and is driven by an eccentric on the pedal shaft. Bore is 3/8" and the stroke is 1/2". The output of the pump has a bypass solenoid on it that returns water to the water tank and has two check valves--one goes to the boiler input and the other to the normalizer.
With 650 F steam, the SteamPed will cruise at 20 MPH filtering water the whole way! In the interest of longevity, I run it at 500 F and get 15 MPH. My wife Kathleen is not quite sure a bike running on plumbing parts and water filters it is her cup of tea but she looks like she's having fun!