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single fire vs. dual fire

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Old Apr 20, 2006 | 04:39 AM
  #1  
lowglide88's Avatar
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Default single fire vs. dual fire

I'm thinking of upgrading my ignition...I know you really don't get much performance from ignition..would single fire be better...or would a good dual fire.. be just fine...I'm runnin an 80 in Evo with S&S heads,pistons and 520 lift cam, 10:1..also I have a SE ignition module,if I choose to go with a Crane kit..that has everything on the sensor plate..can I use that module or do I need to put the OEM module back on..I'm just throwin this out there to get some opinions on it.
 
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Old Apr 21, 2006 | 01:08 AM
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Shovelhead Bob's Avatar
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Default RE: single fire vs. dual fire

Dual Fires are nice, but more for performance motors... Most Dual Fire setups, the 2d spark is a wasted spark anyways... Get a good single Fire, and you can, if you choose, retain the SE module, and look at getting an "Adjustable Curve" Ign Module... Gives you the flexibility to fine-tune your performance requirements, along with maintaining your rideability....

 
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Old Apr 21, 2006 | 02:16 PM
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Default RE: single fire vs. dual fire

thanx for your input shovelhead bob
 
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Old Apr 21, 2006 | 02:23 PM
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Default RE: single fire vs. dual fire

ORIGINAL: Shovelhead Bob

Dual Fires are nice, but more for performance motors... Most Dual Fire setups, the 2d spark is a wasted spark anyways... Get a good single Fire, and you can, if you choose, retain the SE module, and look at getting an "Adjustable Curve" Ign Module... Gives you the flexibility to fine-tune your performance requirements, along with maintaining your rideability....

I think there is some confusion here. The Dual Fire is what is stock, fires both cylinders on each stroke. The Single Fire modules use to be race only but some of the newer systems actually give you a bit of gas mileage and horsepower increase. What the Single Fire is best for is a decrease in vibration in the EVO engines. Then to take it further, the Daytona Twin Tec has a multi-spark mode that decreases the vibration even more.

There has been some confusion on this over the years and even some manufactures have mis-used the terms. Go here for more information:

http://www.daytona-twintec.com/tech_ignition.html
 
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Old Apr 21, 2006 | 02:40 PM
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Default RE: single fire vs. dual fire

I will testify to Daytona Twin Tec's claims.

I had a Dual Fire system in my custom bike (94 Evo engine). I put in a entry level Compu-Fire Single Fire ignition and it ran smoother, less midrange vibration and my gas mileage increased a couple of mph.

Then I spoke with the folks from Kendall Johnson at a show and they have been using the Daytona Twin Tec 1005 in their customs and sell the unit under their brand name. I bought one, I already had a Daytona Twin Tec Single Fire coil. Installed it in the Single Fire Multi-Spark mode and tried a few of the standard advance curves for the street and settled on number 6.

Things ran great, less vibration in the mid and high RPM than the Compu-Fire.

Well something failed and the unit is back for repair. That happens will all electronics sometimes.

I put the Compu-Fire Single Fire system back in and noticed the mid and high rpm vibration came right back.

If you want to play, the Daytona Twin Tec 1005 has a computer interface and you can program your own advance curve.
 
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Old Apr 21, 2006 | 06:11 PM
  #6  
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Default RE: single fire vs. dual fire


ORIGINAL: ThudMeister
I think there is some confusion here. The Dual Fire is what is stock, fires both cylinders on each stroke. The Single Fire modules use to be race only but some of the newer systems actually give you a bit of gas mileage and horsepower increase. What the Single Fire is best for is a decrease in vibration in the EVO engines. Then to take it further, the Daytona Twin Tec has a multi-spark mode that decreases the vibration even more.

There has been some confusion on this over the years and even some manufactures have mis-used the terms. Go here for more information:

http://www.daytona-twintec.com/tech_ignition.html
Agreed.

A single fire will also improve starting. I wouldn't think twice about using a single fire ignition.
 
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Old Apr 22, 2006 | 11:02 AM
  #7  
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Default RE: single fire vs. dual fire

springer and thudmeister...thanx for your input as well..
 
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Old Sep 13, 2006 | 01:59 PM
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Default RE: single fire vs. dual fire

I cannot find info on whether my 05' 883 sportster is a single fire or a dual fire, I know all older ones are but not sure of 04 and up. My coil has a plugin in it with 3 wires, not 2 like the old ones, any help, will putting an aftermarket module not help that much if I am already single fire????
 
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Old Oct 5, 2006 | 02:05 PM
  #9  
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Default RE: single fire vs. dual fire

C,mon no one knows? I found a nice small aftermarket tach, but it says it will only work with single fire, So I need to know if it will work on my 05 sportster.
 
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Old Oct 5, 2006 | 05:33 PM
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Default RE: single fire vs. dual fire

Your bike is a single fire. Some sportster have a factory tach, and some don't. Check your service manual, and look for the tack feed pin. Tap it off there just like a stock set up.
 
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