Backfire on startup

[hdfatboy02]

Ever since I installed my PCIIIr every so often my bike will do odd things at startup. It is not all of the time (only a handful), but the latest is a full fledged backfire. Not a pop but a backfire that made me jump 3 ft. in the air. After that everything was fine and it ran great. I have downloaded the correct map for my setup so I don't know what the deal is. I am about to take the Power Commander and V&H off and put my cycle shack pipes back on (it ran flawless back then). What causes a backfire on startup? Any suggestions on what I can check out myself?

[Boom]

Ever since I installed my PCIIIr every so often my bike will do odd things at startup. It is not all of the time (only a handful), but the latest is a full fledged backfire. Not a pop but a backfire that made me jump 3 ft. in the air. After that everything was fine and it ran great. I have downloaded the correct map for my setup so I don't know what the deal is. I am about to take the Power Commander and V&H off and put my cycle shack pipes back on (it ran flawless back then). What causes a backfire on startup? Any suggestions on what I can check out myself?

First thing I'd do is remove the PCIIIr from the circuit and connect ECM back to normal. If it backfires without PCIIIr, call V&H support. If it doesn't backfire without PCIIIr, call Dynojet support. Bad download perhaps?

[DaBaTT]

Ever since I installed my PCIIIr every so often my bike will do odd things at startup. It is not all of the time (only a handful), but the latest is a full fledged backfire. Not a pop but a backfire that made me jump 3 ft. in the air. After that everything was fine and it ran great. I have downloaded the correct map for my setup so I don't know what the deal is. I am about to take the Power Commander and V&H off and put my cycle shack pipes back on (it ran flawless back then). What causes a backfire on startup? Any suggestions on what I can check out myself?

Shoot I have V & H staggards on my fatboy no pciiir or usb yet and it backfires every so often, I kinda get a kick out of it as it sometimes scares the crap out of anybody sitting on my right side :flamejump

DaBaTT

[hdfatboy02]

First thing I'd do is remove the PCIIIr from the circuit and connect ECM back to normal. If it backfires without PCIIIr, call V&H support. If it doesn't backfire without PCIIIr, call Dynojet support. Bad download perhaps?

Well I disconnected the PC, took out my Thunder Monsters and put the V&H baffles back in my Straightshots. Good news is it fired up without a hitch and just seemed to run healthier. Bad news is my pipes are not as loud, the popping on decel is back and I notice a big drop-off in power. I guess I need to put the PC back in and get a dyno run done on it and just be done with it.