rear cylinder fire problem

[Rider Burak]

hi to all, I have a very odd question, I ride a 93 Heritage installed with Andrews EV13 cam, Fireball HI4E module, dyna coil, s&s Super E carb and kick start, for like 4 months I have a very irregular rear cylinder no-fire problem, I have done many settings and re-adjustments but I  can never run it properly for longer than 30 minutes...Could it be the fuel ?? or Fire Ball Ign module settings... can anyone help me ??

[Rugby_fxdwg]

The coil needs to be a Fireball, dyna ignition is a different ohms then Crane

[rageglide]

I've been running crane ignition with the green dyna single fire coils for years without issues.     As I recall the single fire dual coil (single unit) should be fine from either crane or dyna.  (I think those are 5ohm coils).  That said I had multiple failures of the crane single fire coil, ditched it and went to dual dyna stick coils (green).

If it was a cone ignition I'd drop blame squarely on the hi-4 because their failure pattern is to drop a cylinder when they get hot.  But in this case could be the pick up itself with a problem.   Or a coil problem too.   For that matter, if voltage at the ignition drops below 9V on a crane you'll have problems.  My old softail required a relay to bypass the oem wiring which was becoming a problem due to very high resistance causing nasty voltage drop.

Lotta things to check with a handy dandy digital voltmeter.  Check both cold and hot when you have the problem.