I added a HP Corse exhaust to my 08 910S and while the sound is quite pleasing she feels like she's running a bit too lean which I guess is to be expected. Only mods are cat removal and derestricted airbox. Spoke to a mechanic friend who suggested a Rapid Bike ECU upgrade, while another mentioned the B4 gets finicky when messing with the ECU. I'm on a bit of island when it comes to MV mechanics here in New Mexico, the closest being in AZ. I'm certainly sure I could find a dyno though if need be. Any tips appreciated.