I have a 04 heritage with stage 1 download hd open air box and screaming eagle double barrels. I washed the bike and after i started to get decel popping what could have caused this.

 

did you soak your air filter? my buddy got his all wet once and ran like **** till it dried out

 

my guess would be:
Wet plug wires+crossfire+misfire+uncombusted a/f mixture+hot exhaust=pop pop pop
or
Wet filter+restricted air flow+rich mixcture+unburned fuel+hot exhaust=pop pop pop
or
gremlins
Just my guess though

 

Bike has continued to pop even after dried. Started 3 months ago and now i also get a cough out of the air cleaner when shifting from first to second gear and on startup now.

 

I'm surprised it hasn't been popping all along. I have the same setup on my '03, with SEII "competion" pipes. It popped on deceleration all the time and coughed under hard acceleration.

I swapped out the exhaust, the SEII's were way to loud, and installed a Power Commander III from the Fuel Moto people and is have been great ever since. You can leave the pipes if you like them, Fuel Moto will map the PCIII to match your configuration.

 

I added a vance @ hines fuel pak popping gone but I still get coughing through the air cleaner.