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Thread: Oddball engines and prototypes

  1. #2566
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    10th February 2005 - 20:25
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    1944 RE 1
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    I know it's a little off the two wheel track and it's possible that it's been mentioned before, but ……….. this has to be the ultimate in fun and even I might be able to use it!

    https://www.youtube.com/watch?v=qSMWEd54NcA
    Freedom of speech is important but if what we say is considered incorrect by our peers, they will quickly put us right.
    P.C. will eventually destroy our right to tell the truth.

  2. #2567
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    28th November 2013 - 21:58
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    Dawes Jaguar
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    Just found out about these. Most outboards have reed valves into the bottom of the crankcase but Mr Martin thought different, apparently. I've seen automatic inlet valve two strokes in museums and books but these are timed by eccentrics on the crank.

    https://www.joeoutboard.com/manuals/martin-manuals.html
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  3. #2568
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    1st May 2016 - 13:54
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    [QUOTE=guyhockley;......these are timed by eccentrics on the crank.[/QUOTE]

    That's keeping it simple, a bit more work to change the timing, but!

    Cheers, Daryl.

  4. #2569
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    1st May 2016 - 13:54
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    Quote Originally Posted by WilDun View Post
    I know it's a little off the two wheel track and it's possible that it's been mentioned before, but .. this has to be the ultimate in fun and even I might be able to use it!
    That does look like a whole lot of fun!!! So long as it's fitted with a decent 2 stroke engine.

    Cheers, Daryl.

  5. #2570
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    13th June 2010 - 17:47
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    Quote Originally Posted by guyhockley View Post
    Just found out about these. Most outboards have reed valves into the bottom of the crankcase but Mr Martin thought different, apparently. I've seen automatic inlet valve two strokes in museums and books but these are timed by eccentrics on the crank.
    Perkins in the UK did something very similar in the 50's. Drawing and pics in Irvings 2 stroke book - which i've misplaced.

    Friend of my father's had a Perkins 40HP with this setup. Went quite well too.
    Reason is a tool - remember where you left it..... The late, great, John Clarke

  6. #2571
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    10th February 2005 - 20:25
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    Quote Originally Posted by Pursang View Post
    That does look like a whole lot of fun!!! So long as it's fitted with a decent 2 stroke engine.

    Cheers, Daryl.
    That could probably be done I'm sure - a really giant leap forward.
    Not many motorcycle type two strokes available now, (everything is dictated by fashion - nothing is dictated by commonsense!).
    Freedom of speech is important but if what we say is considered incorrect by our peers, they will quickly put us right.
    P.C. will eventually destroy our right to tell the truth.

  7. #2572
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    4th June 2013 - 10:03
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    2010, specialised bike
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    Quote Originally Posted by guyhockley View Post
    Just found out about these. Most outboards have reed valves into the bottom of the crankcase but Mr Martin thought different, apparently. I've seen automatic inlet valve two strokes in museums and books but these are timed by eccentrics on the crank.

    https://www.joeoutboard.com/manuals/martin-manuals.html
    Shouldn't there be a seal between the crankcase chambers?

    Martin engines were manufactured by National Pressure Cooker Company. I think the engines had cams on the crankshaft, as indicated on these patent drawings.


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