Ignition Module Question
Ignition Module Question
Hey folks. So I'm only getting fire on one cylinder with the stock ignition module and coil. It's on a 99 Softail EVO and from what I gather from reading and talking to mechanics, it's the module. The question I have is, has any one ever replaced theirs and if so do you suggest going back to stock or buying aftermarket. If aftermarket, do I need to get a single fire or dual fire? What's the advantages and disadvantages to the single or dual?
Cruiser
Joined: Jun 2011
Posts: 138
Likes: 1
From: Juneau, AK
If your gonna replace your ignition module go aftermarket or screamin eagle, about the same cost as stock plus you get more bang for your buck. I got the dyna2000 HDE module and love it, I stuck with dual fire instead of single... You'll get a lot of opinions on either or.
Cruiser
Joined: Sep 2011
Posts: 236
Likes: 0
From: Ontario, Canada
Hey folks. So I'm only getting fire on one cylinder with the stock ignition module and coil. It's on a 99 Softail EVO and from what I gather from reading and talking to mechanics, it's the module. The question I have is, has any one ever replaced theirs and if so do you suggest going back to stock or buying aftermarket. If aftermarket, do I need to get a single fire or dual fire? What's the advantages and disadvantages to the single or dual?
Cruiser
Joined: Sep 2011
Posts: 236
Likes: 0
From: Ontario, Canada
The question I asked was: Can you explain the difference and the advantages and disadvantages between double fire and single fire ignition modules.
His response was this:
A dual fire ignition module fires twice each cylinder, once at the top of the combustion stoke and a second time while on the exhaust stroke.
The theory behind a single fire is that the second fire is a waste and therefore single fire ignition is more efficient.
He claims unless you were running a high HP monster there would be no difference.
He also stated that an aftermarket ignition module "should" make no difference unless the current module was not working correctly.
I'm not saying a beleive this, I'm only posting it in the hopes of getting clarification and a better understanding. Honestly I have come to trust the information shared by the people here more then my mechanic which I've talked to for a total of fifteen minutes.
Last edited by FXD_One; Jan 20, 2012 at 11:13 AM.
Stellar HDF Member
Joined: Apr 2007
Posts: 3,008
Likes: 463
aftermarket is tuneable, factory is not.
dual fire, fires both plugs everytime. once when needed, once when not.
dual fire, fires both plugs everytime. once when needed, once when not.
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Seasoned HDF Member
Joined: Dec 2010
Posts: 7,736
Likes: 1,524
From: Coromandel Peninsula New Zealand
It is a myth that dual fire is inefficient, the system is designed to give adequate spark at both plugs and spark size has very little to do with power output unless the spark is so compromised that it can't ignite the gas, gas explodes once lit, you just need enough spark to light it.
I have fitted single fire systems for people and couldn't tell the difference...now a tuneable module...that IS a good thing :-)
I have fitted single fire systems for people and couldn't tell the difference...now a tuneable module...that IS a good thing :-)
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Road Captain
Joined: Oct 2009
Posts: 701
Likes: 1
From: The Great Southwest Desert
The firing voltage in a dual fire system is actually higher than in single fire system. The second sparkplug gap that has to be jumped to make the circuit forces the coil to saturate more deeply and that and the extra distance makes the voltage higher to the plugs.
Shittin' Chicken modules increase the rev limit and some have different curves. Aftermarket ones are more adjustable and more apt to be misadjusted.
Shittin' Chicken modules increase the rev limit and some have different curves. Aftermarket ones are more adjustable and more apt to be misadjusted.
Intermediate
Joined: Oct 2011
Posts: 47
Likes: 0
From: Missouri
when my module went south, my mechanic replaced it with a crane cam ignition - I'm pretty sure it's a dual fire - they claimed (and I trust my mechanic to work on MY bike for MY type of riding) that single fire/dual fire won't make much difference unless on a racing/performance type application. I like the idea of everything in one little package - it bypasses the voltage regulator under the seat, which I removed completely.