You can have your local dealer reflash the ECM back to stock. Maybe half an hour labor. They can also tell if it's tuned with the Digital Technician. But have it reflashed there's often an updated version of the map available for older bikes that runs better. Sniff the exhaust? Yeah that'll work. I've had so many guys come in and tell me the bike is rich 'cause they can smell it. Well they're typically very lean. A lean mixture is hard to light and what they're smelling is unburnt fuel. It will fool an O2 sensor too by the unburnt fuel cooling the sensor compound the lean issue..