94 evo rebuild

rode bike 50 miles today, am having an issue with twin tec ignition. when starting kicks back and pops out exhaust,think rear cyl . triple checked instructions, used supplied wires. ran jumper to convert twin tec coil back to dual fire and hooked up stock module, starts and runs. then put twin tec module back on in dual mode starts and runs good in dual mode. module or something does not like single fire mode. was the same in single or multi-spark. or could there be a problem with coil in single fire mode, more likely think module or me is the problem. by the way bike pulls super, no ping or leaks. still waiting on starter, battery, and t/header. did not dare shut it off warm, thanks for all the help and any thoughts on my current ignition problem

What are your current settings for timing on your twin tec?

BP started with instructions on page 3 that has single fire diagram. set mode on position 3 set timming curve on 6 and rev cont at 6x1000 and 0x100. also tried mode on 2 with same problem on start, pop from exhaust- think rear cyl. just started bike now, still in dual fire mode -one pop then started on second try. possible that when cranking voltage drops enough for a bad signal from cam sensor. will wait for battery to try first. thanks for the help.

+1 you can run a delay on fire with the twin tec . insted of it firing on the first rotation you can delay the firing sequence . also did you have compresion releases installed ? that also helps alot. if your above 9.7.