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why in the world would you want to draw power from your ignition system to make a flaming exhaust? You need that power to run the spark ignition system.

Instead of scavenging the coils, build yourself a small voltage amplifier that will run directly off the battery. It takes very little current to fire a spark plug in zero-pressure (atmospheric) exhaust air. Couple the amplifier with a diode or timer if you want, and then you can shoot spurts of flame instead of continuous stream.
 

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#1 the back fire you got upon decell was caused be what is called a lean missfire. This happens on an incorectly jetted bike of anysort. The mixture briefly goes too lean to burn in the cylinder and builds up in the exhaust and once the fuel content is high enough to fire in the cylinder, that flame then ignights the fuel vapers in the exhaust. Ols time hotrodders use to do the flames out of the tailpipe trick all the time. what you have to do to get this to work is ritchen up your air fuel mixture as far as possable and still have the bike able to run.(will cause rideability problems). then you need to get an ignition coil out of a model "A"( they will create a constant spark when hooked up right,( I can't remember how that is right off the top of my head). If you don't have a constant spark, you run a good chance of blowing up your exhaust system.


Good luck on your project.
 

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unfortunatly you are mistaken, and if you hook a coil up to a constant power sorce, all you are going to do is reach it's maximum build up and spark potential. A ciol causes a spark when the power is taken away from the coil and the lines of magnetic fiels collapse and pass through the finer more numerous windings of the secondary coil winding. When the magnetic lines collapse and pass through the secondary coil windings, this induces a voltage multiplied by however many more times the wire is wrapped around the secondary coil in comparison. primary coil supplied with 12 volts with 100 windings can creat 60,000 volts from a secondary coil with 5000 windings.
 

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There should not be any unburned fuel at all going through the exhaust system. That's the whole idea of tuning an engine. You want a complete oxidation of all raw fuel inside each cylinder. You want that complete burn, in the case of a spark ignition engine, to be completed in a constant-volume fashion so that the expanding gases can work on the piston during its full downward motion. Sorry, I'm nearly a mechanical engineer, I know this stuff :p

Blowing up yoru exhaust system is highly unlikely. What he is referring to is a violent backfire caused by a charge of air/fuel not being ignited becuz the spark doesn't happen, exiting a cylinder, and exploding in the exhaust tube. It will damage components, but it will not "blow up" the exhaust. Either way, you don't want it to happen.

There really isn't a "proper way" for the ignition coil to fire when it comes to low current. The lower the current going through the ignition coil windings, the less spark energy you have. See, a spark plug does only one thing for the engine: it adds energy in the form of heat. That heat energy is used to trigger a reaction between the fuel and air. The fuel oxidizes (burns) and turns to inert expanding gases (H2O, hydrocarbons, CO2, NOX, etc) that drive the pistons. If you take electrical enegy away from the coil, although the spark plug may still fire, you may not be adding enough heat energy to fully burn the fuel/air mix in time, which will cause poor performance, poor gas mileage, and the slow clogging of your exhaust ports with carbon, buildup of carbon in the cylinders, and other problems you don't want to deal with. Ignition coils are designed for each application, and there really isn't any sacrificial energy to be leached away from it. Make sense?

If you want to create a flame thrower with the exhaust, it's going to take some more thought than simply leaching spark energy and running the engine rich. What you may want to do is, put some small reservoir of WD-40 or even hairspray. Mount it underneath your seat or somewhere clever like that, and have a small nozzle that is controllable and will spray a mist of the fluid into the very end of your exhaust, behind the muffler so there's no risk of component damage. Build the amplifier I mentioned earlier that will send a high voltage to the spark plug. You'll want a timer that will turn the amplifier signal on and off rapidly to ignite the plug lots of times like a normal plug. All of this can be operated with a very small, very cheap microcontroller. I know it's not the easiest way to do things, but this way would guarantee that everything is safe, and nothing robs power from any other system. I can give more details on this, if you like. Just email me.
 

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And whats the point of this and why would ya wanna do it?? You relize you gotta have this running SUPER rich to get the ignitor to run right?? So its basically just for show. IMO I think itd be kinda lame (dont take it personal, just aint my thing) I dont like it on ricers either.. Hotrods that are flamed out, dont seem as bad, but not on anything newer than 1960
 

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You'd have to shut off your engine kill switch while driving, coasting with the clutch out (engine braking) then open the throttle all the way, filling the engine and exhaust with fuel. Then you can get your flame, with whatever sort of spark device you choose to put in your exaust. It wont be constant, it wont be kind to your exhaust, and it may be unfriendly to your tail light
 

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All that depends on the fact that you have a set of carbs on this bike. If its fuel injected, forget it you have to rig up some sort of aux fuel device mentioned before, and that sounds like a pain.
 

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Leave it to someone to make a kit for something this stupid.
www.flamethrowers.com.au
http://www.hotrodsetc.net/

Id imagine theres a switch you'd install that makes your bike run really rich and you can turn it off/off as yuou want. Thats what i take from their faq. If your bike is carbed then not sure how you`d go about. anyway. I hope you burn your butt and reconsider this stupid idea.


50$Kit includes: http://www.axdo.net/
• Detailed instructions (including where to buy affordable coils & increase flames)
• Control Box
• Power Switch
• Wiring Diagram
• 16GA Power Wire
• Spark Plug(s)
• 30A Fuse and inline fuse holder
• Disconnects/connects - makes wiring much faster
 

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You kids these days with your loud music, britches with the crotch down to your knees now shooting flames out your exhaust........

Back in the old days we'd just eat a load of beans and light a match when it was time.
 

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To quote Susan:

Eeww. That was way more information than I needed to know!
 

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Uncle bob, i`m curious how old are you. i imagine you are a cool 49 year old dude with a beard or goatee maybe long hair and a degree from Cal tech. or Ga tech or something.
 

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TsPerformance said:
Uncle bob, i`m curious how old are you. i imagine you are a cool 49 year old dude with a beard or goatee maybe long hair and a degree from Cal tech. or Ga tech or something.
46 actually !

Receding hairline kept short because long hair was just too much trouble when I had some, clean shaven because of an incident which burned the hair follicles on portions of my face so any attempt to grow a beard ends up with bare patches.

Engineering degree from Montreal Polytechnical institute.

I do think I'm cool though !
 

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Hi, thanks again for the wiring on my engine!!!

So in order for ignitions coils to create some voltage in Kv from a 12v sources, it needs pulses or alternating current.

I think it would be expensive to get an inverter (dc to ac) for you little system, but it would create a constant spark.

A cheaper solution it to put a little manual switch and just press rapidly of the button (on,off,on,off,on,off). You could also I suppose get some kind of timer if you want too.

As for the gaz, I don't think you are supposed/or a good idea to get unburned gaz in you exhaust system. One thing I can think of is a fuel primer (use to pump gaz in your engine before starting it, like in snowmobiles) with a thin nozzle at the end so it would kinda spray the gaz (you dont want it to be liquid).

Let me know what you think!
 

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Wow...I read the title to this thread thinking that for some strange reason, fire was shooting out of someone's exhaust and they needed help on getting it to stop! :shock: I jumped on this thread, not because I knew any answers, but because in the event that MY bike started shooting fire out of the exhaust...I wanted to know how to stop it like NOW!

Then I started reading.... :roll: :roll:
 
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