Go Back   Harley Davidson Forums > Harley Davidson Motorcycles > Evo Classic Models
Sign in using an external account
Register Forgot Password?
Search


Evo Classic Models All Evo Models
Sponsored by: J&M Motorcycle Audio

Welcome to HDForums.com!

Reply
 
 
 
P
 
Thread Tools Search this Thread
  #1  
Old 01-26-2011, 05:30 AM
emwolb emwolb is offline
Ultimate HDF Member
Join Date: Aug 2008
Location: eastern oklahoma
Posts: 5,403
Default ignition, single fire vs dual fire???

what are the advantages of either system, and which system is idiot proof? also, is there a way to identify which system i have on my bike? it's not stock, but all aftermarket and i'd like to know what to look for, if i need to improve anything with the ignition system.
__________________
2013 RoadGlideUltra, all the right stuff.
Reply With Quote
  #2  
Old 01-26-2011, 06:07 AM
Hackd's Avatar
Hackd Hackd is offline
Outstanding HDF Member
Join Date: Oct 2005
Location: Canton, Michigan
Posts: 2,631
Default

I've been running a Dyna 2000, in dual fire mode, on my 93 FLHS since 2002. After a bunch of research, I didn't see much advantage in running it in single fire mode. Add in the addition of another coil (if used in single fire mode), I wanted to use the KISS approach on my bike. There are other, more significant, advantages to replacing the stock HD module with an aftermarket one. Namely rev limiting and ignition curve adjustability.

If you look at a dyno graph of most big twins, you will see that the stock ignition kicks off (limits) just as the EVO is building horsepower. Bumping the rev limiter up to 6000 will get you a fist full of (hidden) power for those occasional corner to corner romps.

IMHO, the whole wasted spark argument, is more of an advertising hype (on a stock compression EVO), than an advantage.
__________________
___________________________
76 CJ5, 5.0L Mustang Engine, T18/Dana 20, Dual ARB's, 4.56 gears, and -way too much money...

In the end...It's all Hack."
Reply With Quote
  #3  
Old 01-26-2011, 08:35 AM
V-Twins & Bowties V-Twins & Bowties is offline
Senior Rider
Join Date: Dec 2010
Location: Illinois
Posts: 493
Default

There is no difference IMHO. I had dual went to single did not notice a thing different.

The reason stockers have dual fire is as simple as lower cost in production.

They're both idiot proof until you get all fancy with the after market systems with numerous bells and whistles.

To ID, Dual fire the coil has two terminals. Single fire the coil has three terminals.
When changing coil/s pay attention to resistance value.

I run a Compufire single fire which is a set it forget it ignition. Its been in three years and so far not a problem.
__________________
Great Southwest

Last edited by V-Twins & Bowties; 01-26-2011 at 08:49 AM.
Reply With Quote
  #4  
Old 01-26-2011, 10:50 AM
98 FLHX's Avatar
98 FLHX 98 FLHX is offline
Senior Rider
Join Date: Mar 2009
Location: St. Peters, Missouri
Posts: 375
Default

...Here's what Nightrider has to say about this topic....

http://www.nightrider.com/biketech/h...ionmodules.htm

http://www.nightrider.com/biketech/hdseignition.htm
__________________
127"
6 Speed
Thunderheader
Reply With Quote
  #5  
Old 01-26-2011, 06:42 PM
t150vej's Avatar
t150vej t150vej is offline
Road Warrior
Join Date: Dec 2005
Location: NC and across the Mississippi every opportunity
Posts: 1,672
Default

The only "real-time" advantages to aftermarket single-fire setups - they allow for different advance curves, dead cranking rev modifications and adjustable rev limiter settings, depending on the manufacturer. I run a single fire and it's of no advantage concerning mileage or power.
Reply With Quote
  #6  
Old 01-30-2011, 01:45 AM
emwolb emwolb is offline
Ultimate HDF Member
Join Date: Aug 2008
Location: eastern oklahoma
Posts: 5,403
Default

thanks for the replies guys. i just got a bike that has a compu fire box up between the front frame rails, and twin coils at 3 ohms each, and i'll pull off what we used to call the points cover to see what rotor is being used there. i can't see any advantage of a single fire over a twin fire, and the motor runs just fine. it's a new bike to me, so i'm trying to figure out what ignition it's using. thanks again.
__________________
2013 RoadGlideUltra, all the right stuff.
Reply With Quote
  #7  
Old 01-30-2011, 09:24 AM
PakMul's Avatar
PakMul PakMul is offline
Prospect
Join Date: Sep 2010
Location: Albany, Oregon
Posts: 178
Default

I put a Daytona Twin Tec single fire module and coil on my Ultra when the stock module died. It made no difference in the starting problem or the running of the bike. Nice to have the adjustable curves and all that since I've changed other parts of the engine since, but the single fire feature didn't really add up to much.
__________________
Savor every ride like it's your last!
1956 Panhead - Stock
2001 Deuce - Andrews, Mustang, Vance & Hines

2011 Electra Glide Limited - V&H, Ness
Reply With Quote
  #8  
Old 01-30-2011, 09:44 AM
Stiggy's Avatar
Stiggy Stiggy is offline
Ultimate HDF Member
Join Date: Nov 2010
Location: Oxford, Nc
Posts: 5,785
Default

If you've got twin coils at 3 ohms, you've got single fire. But like the other posts, there's not much practical advantage.
Reply With Quote
  #9  
Old 01-30-2011, 11:07 AM
topfuel7's Avatar
topfuel7 topfuel7 is offline
Prospect
Join Date: Dec 2010
Location: central NC
Posts: 132
Default

I have the headquarters ignition and a Killer Watts coil. It has the dual or single option. It may depend on the setup of the bike or the igniton box itself because mine does idle different in single fire than in dual fire. I have to adjust the idle if switching between the two and it dosent spit back at all in single fire mode but it will occasionally cough back when in the dual fire mode.
__________________
Reply With Quote
Old 01-30-2011, 11:07 AM
 
 
 
P
Reply

Tags
2010, 99, coils, davidson, dual, evo, fire, harley, harleydavidson, ignitian, ignition, ignitions, ingnition, king, road, single, softtail


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off
Forum Jump

Advertising
Featured Sponsors
Vendor Directory
Sponsors
All times are GMT -5. The time now is 02:33 PM.

Internet Brands, Inc.

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.1

Admin, Emails & Contact Details