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Discussion Starter · #1 ·
Having somehow burnt out 2 petronix kits in the last few months (and no, the ignition wasn't left on) I've decided to revert back to points.

Can anyone tell me if I can leave the flamethrower coil on or do I also have to go back to a bosch coil ?

Cheers
 

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Yeah, you could just stick with the Flamethrower coil.

What I'd do is get one of the transistor ignition kits from Maplins (only £10!) and use that with the points. I've used the same one on my Baja and my Bay since 1998 and haven't had any problems with it.
 

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Bobster said:
Scuse my ignorance but what does that then do ?
A damn sight better than the Pertronix by the sounds of it! ;)

The points are retained but instead of the points doing all the high current switching, there's a huge transistor that does it instead. The result is a damn good spark, better power and fuel economoy and points that last a long time. Make sure the insulation is good on the HT leads as you get a huge spark that will jump quite some distance (I'm not kidding!)

And it does away with the condensor too.
 

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I built one of those kits, too, and fitted it to a Russian bike I've got. Easy to build (and good fun too if you're into that kinda thing) and works very nicely. The main advantage for me is that I could build it into an og Russian regulator box so it's hidden. Makes a big difference to starting especially, and your points don't wear half as much. Worth a punt at £10 (tho mine was £15!)........
 

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How does the transistor ignition increase the spark from the coil?
Not disputing it, would just like to know more.
 

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zac said:
How does the transistor ignition increase the spark from the coil?
Not disputing it, would just like to know more.
Mainly because there's a load of resistance on the points (especially when they're a bit old and worn) so you don't get as good a connection to ground out the coil and collapse the voltage - resulting in the spark.
Whereas the transistor ensures there's always a good connection.

Plus the maplins kit does have a big capacitor on the output so it acts like a very small capacitive discharge (CDI) unit (although I'm not sure if this makes a huge difference).
 

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With the high output coils you used to need a Ballast Resister if using with points......is this what you are talking about?
 

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pellandine-sports said:
With the high output coils you used to need a Ballast Resister if using with points......is this what you are talking about?
You don't need a ballast resistor with the Maplins thingy.
 

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You don't need a ballast resistor with the Maplins thingy.
Okay I'll take your word for it....but what's the difference?

The Maplin thingy is an ignition amplifier....I understand how that works but what does a Ballast Resister do?
 

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As far as I know (and I stand by to be contradicted, cos I've never actually used one, just heard about them):

The idea of a ballasted coil is more HT when starting. The coil primary is wound to give the desired HT output with only about 9V or so on the input.

A ballast resistor is wired in series with the coil so that under normal running, you get the reduced primary voltage. But the ballast resistor is shorted out when you crank the starter, connecting the battery direct to the coil.

AFAIK, you need a specially designed solenoid that will give you the appropriate ballasted/unballasted feed to the coil.

Popular on old British sports cars, I believe.

Hope I'm right, cos it sounds convincing!
 

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tonyhedge said:
As far as I know (and I stand by to be contradicted, cos I've never actually used one, just heard about them):

The idea of a ballasted coil is more HT when starting. The coil primary is wound to give the desired HT output with only about 9V or so on the input.

A ballast resistor is wired in series with the coil so that under normal running, you get the reduced primary voltage. But the ballast resistor is shorted out when you crank the starter, connecting the battery direct to the coil.

AFAIK, you need a specially designed solenoid that will give you the appropriate ballasted/unballasted feed to the coil.

Popular on old British sports cars, I believe.

Hope I'm right, cos it sounds convincing!
Yup, that's pretty much it.
 

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Discussion Starter · #14 ·
Blimey this is getting well complicated. I supose the main question I'm asking is at the moment can I run the flamethrower with standard points without any other additions ?

Cheers
 

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Bobster said:
Blimey this is getting well complicated. I supose the main question I'm asking is at the moment can I run the flamethrower with standard points without any other additions ?

Cheers
Yeah. Coils will only generate as much power as needed so that shouldn't be a problem.
 
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