Do I have to add a Power Commander or reflash the ECU when I install a Dobermann Performance exhaust and/or headers ?
Again, this is an area where there is an incredibly high amount of false and outdated information floating around the web, and thousands of home spun theories.
The fact is that you can install your new exhaust and header pipes and go out and enjoy your bike without any additional modifications – the modern engine management system will take care of things for you and keep your engine safe.
All the confusion on this topic has its origins in the past: Back in the days when motorcycles had carbutettors, you had to install bigger main jets to compensate for the increased air flow in the aftermarket exhaust. Same thing for the first generation of fuel injection system (Mostly on bikes made before 2007), where the programming is fixed and there was no lambda O2 sensor to measure and adjust the air/fuel ratio.
Modern fuel injected motorcycle engines all have one or more O2 sensor(s) in the exhaust system, which will measure the air content in the exhaust and adjust the air/fuel ratio. So the O2 sensor will adjust the air/fuel mixture to compensate for the new exhaust, and that is why you can install your new exhaust without fear of engine damage.
You may have a bit of backfire on engine braking where the ECU will ignore the O2 sensors input, but that is a (sound) cosmetic issue and not a problem for your engine.
NOTE: The O2 sensor can obviously only do it’s job if it is installed, so it is a very very bad idea to remove the O2 sensor and install one of the common O2 sensor eliminators. The O2 sensor eliminators/dongles are a popular mod because they are cheap, but eliminating the feedback system to the ECU is about the worst trhick in the book, so stay away from this (non) solution !!!