Removed baffle-Bike Backfired 10 times-Now no Spark!

[AjG]

New to forum here.
I have two Vintage CBs, a 73' 350 Four that has been cafe'd a bit. And a 74' 750 Four that is mostly stock at this point, but the previous fella put in a new Power Arc (Dyno?) ignition. It is a new piece of technology that sits in the distributor housing. I have had the bike 3 weeks and it was running like a dream. At purchase it had no baffle in the muffler and sounded amazing. He gave me two baffles with the bike. I have only played with putting one in. Rode with baffle in for about 1 week.
I Went to a car and bike show last night and pulled the baffle out so that it would sound as good as it looks. I noticed on the way to the show that in 4th and 5th gear a hesitation occurred when I wrapped the throttle on the expressway to pass cars and get up to speed. These were the 1st lurches or glitches I have noticed. But I arrived with no incident.
I Enjoyed the show and had some nice reviews. After the show a guy and I decide to head on down the road for jaunt and I'm backfiring out of the parking lot?
5-10 backfires later the bike in motion and going 40 mph....the motor cuts off. I Squeeze in clutch for neutral, drop a gear and release, and the bike pop starts, but isn't responding to throttle. In fact gas stalls engine. I repeat pop start maybe 3 times to get engine going. It rumbles, but isn't idle. Hitting throttle continues to kill engine until I coast to the shoulder.
Bike will not start. Fortunate to have been with someone. I get a ride to fetch my truck and get the bike to my garage.
We pulled the plugs and they are soaked. Dried em out, whisked em off, grounded them and tried to see if we had any action......no spark.
Bike turns over, but I get no fire.
Any suggestions or experience with this type of ignition or backfiring that would kill the spark?
Any thoughts would be appreciated. Kinda new to biking too, so I'm at the left side of the learning curve here. Hopefully this isn't too big a deal and will help me learn something....

[Re-run]

Backfire would not kill the spark. Can you get a pic of the ignition?
Are you sure there is no spark? Pull the plugs out and ground them on the head, turn off the fuel and crack the ignition. See if the plug sparks. If the plugs spark, then that should not be an issue, should be a blue spark.
What you may want to do is run through a basic tune up procedure. Pull out the plugs, pul off the points cover, what you called the distributor cover. Remove the 8 valve cover caps. Get the timing marks to 1-4 T and check valves.
There is a trick for this. At 1-4T, you can check either both sides of 1 or 4 and the intake of or 2 or 3 and the exhaust of 2 or 3. (Cant remember which order off the top of my head). Set your intake to .004 and exhaust to .003. Manual says .003 and .002 but the added space helps the valve train last longer.
Rotate around to 1-4 and again and do the rest of the valves.
After that, rotate the crank back about 15 degrees and set the timing change tension.

After that, make sure you had fuel flow to the carbs. If the line is blocked, it could have gotten real lean and backfired and there may not be enough fuel to start.

Course, if you have no spark from the first test, try to contact the Previous owner and see if you can get a receipt or something or contact dyna if it is a dyna.
If the ignition is dead, you can either go back to points or get a new ignition. If you choose a new ignition, I suggest the pamco ignition. You can order it from a link we have here. From what I have heard, it is a pretty decent ignition.

[AjG]

Definately no spark.
Pulled the origional plugs, grounded and tested to no luck.
Put in new plugs to retest, same result.
Fuel is not the issue, I have flow.
I realize now the "distributor" cap is my points cover. Thank you...a bit green here.
I was given the origional points parts. I would like to reinstall based on several recomendations to do so.
The ignition installed is from Power Arc. I have some paperwork on that and will contact them.
When the condition occurred I was under power like I described. I believe it started mildly with hesitation upon throttle in 4 & 5th gear. Bike decelerated when I hit gas, sputtered and lurched.
It started popping on subsiquent ride and then just died while in 4th going 40 or so... I could get the engine to a slow sputtering rumble via pop start, but throttle would kill engine immediately.

[Re-run]

Well, toss on the points and get your gap set to spec and timed and see if it helps. It will take about an hour to do that. It does sound like the ignition died but this will tell you for sure.
Looks like the power arc is programmed, so maybe contact them and see if maybe the programming can be wiped out somehow by accident. It may be that the ignition is still good but lost its programming.