Plug spark

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StueyC
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Plug spark

#1

Post by StueyC » Thu Nov 11, 2010 5:44 am

Is it normal for the plugs to spark when you turn the inginition switch on and then off with the motor not running?

StueyC



john HD
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Re: Plug spark

#2

Post by john HD » Thu Nov 11, 2010 6:10 am

if the points are closed it could be possible.

john

StueyC
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Re: Plug spark

#3

Post by StueyC » Thu Nov 11, 2010 9:56 am

I have a hall effect ignition fitted John. I spoke to one person who said it was normal for this to happen on harleys from 60's through to 70's?

Sounds strange to me. If you happen to leave it in gear when stopped and turn the ingintion through to lights and then turn them off again the motor can fire from residual fuel in a cylinder and lurch forward.

The only reason I found out was because I did just this and the motor backfired through the carby. Bit of a surprise when your not expecting it.

StueyC

JR JOHNSON
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Re: Plug spark

#4

Post by JR JOHNSON » Thu Nov 11, 2010 3:21 pm

hi, my dyna s ignition do the same thing,if you dissconect the battery,put a battery charger on it,it sets there and keeps on firing, what i understand that surge of energy will triger the switch,if its in a closed,like points mode,it will do it,just part of life,with the hall switch. .....with respect.....JR...

kitabel
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Re: Plug spark

#5

Post by kitabel » Thu Nov 11, 2010 6:18 pm

I had a panhead cough and rotate when I hit the switch, almost lit up my eyebrows.
Why unusual?
I just took of the Linkert - the gas remaining in the manifold ignited.

StueyC
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Re: Plug spark

#6

Post by StueyC » Thu Nov 11, 2010 10:59 pm

Thanks JR.

Kitabel, were you running points or electronic ignition?

StueyC

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Re: Plug spark

#7

Post by james » Fri Nov 12, 2010 1:38 am

I've had it happen with points and the E-beyond 2000.
When I turn the switch I always wonder if it's going to fire off.
It's like a swoosh sound. Pretty cool

jim

StueyC
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Re: Plug spark

#8

Post by StueyC » Fri Nov 12, 2010 2:01 am

Thanks James. sounds like it's normal then so I'll learn to live with it. Never had it happen with my Shovel but then again I've never checked if the plugs spark like the pan when the ignition is shut off.

Nothing wrong with bit of a heart starter every now and they hey?

StueyC

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Re: Plug spark

#9

Post by FlatHeadSix » Fri Nov 12, 2010 2:16 am

Stuey,
As everyone has already told you, its normal, and nothing to worry about. The OEM ignition systems were "wasted spark", every time the points open both plugs will fire. Turning the ignition switch on-and-off is the same as the points closing and opening. I imagine that a Hall Affect sytem behaves much the same way.

On the OEM points & coil systems you can sometimes (if you're lucky) amaze your friends by giving the engine a few primer kicks, make sure you leave it on a compresion stroke, take the dust cover off the circuit breaker and "flick" the end of the arm on the points: engine starts! WOW say your friends ("lucky" says you). I've done it, but it sure won't work every time!

mike

StueyC
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Re: Plug spark

#10

Post by StueyC » Fri Nov 12, 2010 2:45 am

Thanks Mike.

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