I have a 1994 Softail Heritage Classic HD. Since 1995 it has crane cam, in it adjustable push rods, hi flow pet ****, big 8 millimeter wires, super ESS carburator, fireball dual spark coil, Hi-4 crane cam ignition. Since 1995 it ran good sat for a year and a half. Idle is good, runs good, until you get to 5th gear and crack the throttle and it starts popping out of the exhaust. I rebuilt carb, rebuilt accelator pump, replaced manifold gaskets, replaced manifold o rings, rejetted the carb 4 times, put new spark plugs, put new dual fire coil on it. And it still pops out the exhaust when you crack the throttle in 5th gear. What could be wrong with it? I am out of ideas. It the carburation or is it the ignition? Thanks

 

Only in 5th gear? That's weird. What RPM in 5th?

In general, a pop out the carb is too lean. Too fat is falling on it's face when you open it up. Actual backfires out the exhaust, well, I've seen it with an exhaust leak, but mainly on reversion. A lot of people had trouble with those Hi-4 ignitions.

 

I think about 3000 rpm's but it doesn't have a tac

 

Disconnect the voes and see if it still does it....

 

Try new plugs and gap them a bit closer-
you are describing what the secondary side if the ignition will do when it breaks dwn

 

Thanks I already tried that and it did the same thing But thanks!

 

I put new plugs in but it did the same I will put new plugs in and try gapping them closer I gapped the old ones at 40. Thanks!

 

What Jets are you currently running and is there cylinder head work or Pistons... ? Do you know what the compression is?
also did you disconnect the voes and try it?