Propane Powered 4-srtoke????

Discussion in 'Performance Mods' started by PUTT'IN'PTOWN, Oct 9, 2010.


    PUTT'IN'PTOWN New Member

    Hey All Would'nt A propane powered 4 strke be neat propane cheaper more
    green??Anyone ever SEE ONE OF THESE!!! THIS THING IS COOOOL I wish i
    could afford one or build one you can do almost anything with one of these!!
    RIde to work cross river on the way hehe Just shows if you can think of it
    Someone has probably done it!! for the Propane you would have to change
    the CARB!!! but it could be done they have generators that have PP Carbs!!

    STay HAPPY Keep Ride-N-!!
    Fast Be safe!!:taz:

    Attached Files:

  2. robin bird

    robin bird Member

    Wow i love it --what next ??
  3. philski

    philski New Member

    You sure can, its the same as any car run on LPG

    The propane you buy will be pressurized so direct injection through the mouth of the carby or inlet manifold /

    it will give you a solid boost as an extra to petrol. Propane is only slightly more powerful than gasoline.
    However, gains in its gas expansion, because it is so much cooler. More than make up for it. But it is down on gasoline's power. ask any Liquified gas car driver.

    You dont need to do anything to your valves so that is a bonus, steel valves are fine.

    also, because it is being jetted it will cool your engine considerably, as it goes through phase change from liquid to gas. Good but, be aware, aluminium expands and contracts much faster rate than iron. like your crank housing/flywheel, bore, etc. so allow it time to reach Equalibrium with short bursts. there are also propane mix's on the market. like propane / butane etc, some reach 1100c and 1300c so get the highest rating you can.

    the photos of the bike boat/kayaks are awesome too.

    Kindest Regards
    Last edited: Oct 14, 2010
  4. HeadSmess

    HeadSmess Well-Known Member

    um, scuse me....i couldnt help noticing that...


    what the? ?!!!! :jester:


    flippin lunatic...

    but yeah...lpg aint terribly hard, except metering to get a consistent mixture through the rpm range is tricky... usually idle and wot for us guy anyways...

    and, iunno bout where you are, but i dont think theyll be too keen on me filling me bike at the auto lpg bowser around here... plus getting it in prefilled bottles is hella expensive...

    find a source of ca carbide and mix with water...hey presto! acetylene!
  5. motorpsycho

    motorpsycho Active Member

    well, think about lugging a 20 pound tank of l.p. around, strapped to your bike.
    sure, you could get a smaller tank, but it would not last very long.
    I'll stick with gasoline thank you.

    by the that last pic, that guy is hauling a 200 + pound deer in a trailer with a pedal bike UPHILL????
    no thanks, that looks like too much work.

    the guy in the pics. looks like a total moron on that thing if you ask me....but that's just my opinion.
    Last edited: Nov 12, 2010
  6. DougC

    DougC Guest

    Propane is a lower energy density than gasoline,,,,,, I think propane is 40% of the energy?

    So what that means is you would need to carry 2.5 gallons of propane just to equal the range of 1 gallon of gasoline.......

    (this is also the reason that propane-fuel trucks usually have a big tank in the bed behind the cab, and don't use the space of the original gasoline fuel tank)


    Propane does have one advantage in that (being an evaporative gaseous state at normal temperatures) it never fouls the carb. This is why so many forklifts use it.

    Propane is preferred for forklifts and other similar loading-dock and factory-yard machinery when they are only used occasionally. A gasoline or diesel engine would get carb-fouling (for a gasoline engine) or fuel-fouling (for a diesel engine) from all the time they would sit unused, but propane doesn't do either.
    Last edited by a moderator: Nov 16, 2010
  7. loquin

    loquin Active Member

    there's an outfit (Lehr) making 25cc propane powered weed whackers. They get about two hours out of the camping style 1 pound propane cylinders.

    Daves Discount Motors is selling the Lehr engine. They have a 54mm clutch, though - not the 78mm that's pretty much the standard we use..
    Last edited: Nov 17, 2010
  8. happycheapskate

    happycheapskate Active Member

    I think the Lehr propane 4x engine (25-32cc) gets about 40mi on a 1 lb green can. You could easily carry 3 or 4 total cans on a bike.