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Discussion Starter #1
I just had an awkward problem this morning tha tmay have started yesterday. yesterday i was having spark issues after washing my bike, no pressure washer just a gentil rinse. I noticed some cracks in my coil so i swaped it out with another that i had and problem solved so i thought.

I have a boyer elec ing in the bike running a 3ohm harley style twin fire coil. I think the one that i replaced it with may have been a 6 ohm coil. even thou it fired right up yesterday and shut off normally, today when i arrived at work and i keyed it off it kept running. not the slightest indication that i turned off the key. I had to pull the boots on the plugs.

The key seems to be working fine in respect to how the brake lighe fuctions in pos 1 and all lights in pos 2 and everything off in pos 0.

I dont know if the coil with a different ohm is still recieving enough from the ele ing to fire or did i fry something in the ele ing?
 

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Electronics.....It'll never catch on.

Which Boyer unit are you running?

The Mk3 has a limit on the coil resistance of 4ohms MIN
Any less and the current drwn by the coil will cause the unit
to overheat, and the coil will get hot due to the high dwell that
the unit provides.

The Micro Digital unit can use low primary resistance coils as it
employs current limiting.

Need to know which one and how you've wired it.

Nick
 

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Discussion Starter #3 (Edited)
A little more info to help with the issue.

Its a MK3 kit. The coil that I removed measures 3 ohms and the one that’s on it now measures 3.6 ohms.

When I turn the key off the bike still runs as stated and I measured the voltage at the coil. With the key on and the bike running voltage is at 13.4 at the coil, with the key off the voltage dropped to a 8-9 volts.

I have checked, double checked tippled checked everything including the ignition key and the key is not passing power through it with the key off.

Lastly the most important find is I found that even with the key off if I kick it the coil is firing.

Somehow when you kick the bike the electric ing is firing the coil even with the key off and the battery isolated form the system.

The magic black box is the only thing I can think of that is allowing the bike to fire as it sends the signal/voltage to the coil.
 

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I think you should double check your power wiring to the Boyer box, and ensure you aren't also feeding power to the coil. I think maybe a hotwire situation exists.
 

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Is the bike wired for + or - Earth?

I know these things can be frustrating but you'll probably find that something stupid is causing this.

For the unit to provide a spark at the coil it MUST have a supply
on it and an earth.(8-16 volts across it)
If the bike runs without the ignition switch 'on' then either a wire
is connected incorrectly or one has shorted to earth somewhere.

Let me know if it's pos or neg earth.
I'll dig out some drawings.

cheers
 

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I think you said it yourself, you washed it. I reckon you have water in some wireing somewhere that is allowing power past where it shouldn't. try low pressure compressed air to blow all the wires:cool:
 

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Discussion Starter #7
Is the bike wired for + or - Earth?

I know these things can be frustrating but you'll probably find that something stupid is causing this.

For the unit to provide a spark at the coil it MUST have a supply
on it and an earth.(8-16 volts across it)
If the bike runs without the ignition switch 'on' then either a wire
is connected incorrectly or one has shorted to earth somewhere.

Let me know if it's pos or neg earth.
I'll dig out some drawings.

cheers
its neg earth. i believe the "short" is inside the boyer box.
the wiring on the bike is solid as that is one of my specialitys and i have been running it like this for 2 years now without any problems.

i actually tried to put the first coil back on it this morning and it fired once but not enough spark to catch so i am thinking that not only is the first coil dead but it may have created a short in the boyer box.
 

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Discussion Starter #8
I think you said it yourself, you washed it. I reckon you have water in some wireing somewhere that is allowing power past where it shouldn't. try low pressure compressed air to blow all the wires:cool:
normally i would say thats a good idea but any connections are soldered and sealed with shrink tubing.
 

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The keyswitch internal connection to the ignition may be corroded to a point of fault. The lighting contact in there might still be okay, hence the visual cue that the lights go out, but the ignition stays hot. Test this by pulling the ignition hotwire off the keyswitch terminal.

Otherwise, it's definitely water-related. the Boyer box has no way to attach 12v from anywhere inside it except via the "hot" wire.
 

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From your last post i think the question is answered.

When you put a lower resistance primary coil on the bike you get little or no spark.
With a higher resistance coil it runs,
This is indicating a high resistance connection supplying the ignition system. ie more current = less volts

I tend to think its the ignition switch has water in it if all the joints are soldered and sleeved.
 
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