Finding Top Dead Centre

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Tolly
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Re: Finding Top Dead Centre

Post by Tolly »

Iron Head wrote:That Bantam owner was obviously a West Ham supporter. Don't forget too the legend that states that Bantams can fire up and run in reverse. Don't know if it is true but years ago a mate of my brother's reckons he started his D7, put it in gear and it went in reverse?!
Yes I've seen that done, not sure of the model of bantam as I was only 15.
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spookefoote1956
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Re: Finding Top Dead Centre

Post by spookefoote1956 »

"With my gears in reverse, the other way round I'll finish first
Oh! Come along and see me riding in the T.T. race"

Is it true they go faster that way?
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SPRIDDLER
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Re: Finding Top Dead Centre

Post by SPRIDDLER »

The Dolphin 2-smoke seawater-cooled marine aux engine was designed and produced in the 40's by the brilliant designer/engineer, Harry Ricardo. To go from Ahead to Astern one stopped the engine, threw a switch and restarted it running 'backwards'. The main drawback was that you had to stop the engine, usually when you most needed to slow down, and 2-smokes are often notoriously difficult to restart when hot........... :oops:
Around 55 yeas ago, knowing that I was an apprentice motor mechanic a pal coerced me into sorting out his unreliable single cylinder Dolphin of approx. 3 HP on a good day. The restarting (by hand crank) when hot problem was more or less cured by replacing the crankshaft seals which when hot would soften and leak, seriously reducing the crankcase pressure.
Mind you, that was just about still in the days when many self-respecting yachtsman wouldn't dream of using a motor to pick up a mooring.
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Peter Morris
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Re: Finding Top Dead Centre

Post by Peter Morris »

Expat wrote:
Get it over tdc too quickly and schlooooop........instant chalfonts :o

:lol:
Chalfonts............ posher than Farmers? :rofl:
JimFitz
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Re: Finding Top Dead Centre

Post by JimFitz »

SPRIDDLER wrote:The Dolphin 2-smoke seawater-cooled marine aux engine was designed and produced in the 40's by the brilliant designer/engineer, Harry Ricardo. To go from Ahead to Astern one stopped the engine, threw a switch and restarted it running 'backwards'. The main drawback was that you had to stop the engine, usually when you most needed to slow down, and 2-smokes are often notoriously difficult to restart when hot........... :oops:
Around 55 yeas ago, knowing that I was an apprentice motor mechanic a pal coerced me into sorting out his unreliable single cylinder Dolphin of approx. 3 HP on a good day. The restarting (by hand crank) when hot problem was more or less cured by replacing the crankshaft seals which when hot would soften and leak, seriously reducing the crankcase pressure.
Mind you, that was just about still in the days when many self-respecting yachtsman wouldn't dream of using a motor to pick up a mooring.
Also how the old Villiers engined Bond three wheelers worked. Stop it, throw a switch and start in reverse. It allowed you to do the same speed in reverse as forward :o
I found that as the steering turned the engine and front wheel up to 90 degrees you could do high speed donuts without burning rubber although it was possible to turn it greasy side up!

Jim
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Pharisee
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Re: Finding Top Dead Centre

Post by Pharisee »

JimFitz wrote:
Also how the old Villiers engined Bond three wheelers worked. Stop it, throw a switch and start in reverse. It allowed you to do the same speed in reverse as forward :o
I found that as the steering turned the engine and front wheel up to 90 degrees you could do high speed donuts without burning rubber although it was possible to turn it greasy side up!

Jim
Not just the Bond... My mate had 'bubble car' back in the sixties that worked that way. The engine had two sets of points set equally, either side of TDC. Stop the engine, turn the ignition switch the other way and press the start button. It reversed the polarity on the 'dyna-start' generator/starter motor, and used the other set of points to fire up in the reverse direction.
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