My 2010 Roadster was dynotuned today.
The system has a stock motor with a Ramair intake, Viking headers and a SuperTrapp muffler. I was running a TuneECU tune. The bike was running rich before the dynotune.
The bike picked up about 10hp and about 10ft/lbs of torque.
The most important improvement was at 2500rpm where the bike picked up about 90hp and over 30 ft/lbs of torque. The old tune wasn't good with this intake/exhaust combo.
The bike runs smoother and faster and should get much better fuel economy.
For those looking at a Viking Exhaust this should give you some idea of the improvement you can expect.
I am very happy with the result.