How dirty was the air filter?
Anything restricting the Exhaust? Dings in the Exhaust? The spark arrester in the Exhaust clogged?
Did the bike feel on song or was it down on power?
Change the plug anyway it’s cheap
I wonder if Dealers have a diagnostic tool that plugs into the EFI Computer and can display the sensors outputs so you can see what the readings are? There are only a few key sensors in an EFI system:
Air Temp (Diagnostic tool should show a value in Degrees C or F)
Coolant Temp (Diagnostic tool should show a value in Degrees C or F)
MAP (Diagnostic tool should show a value in KPa or PSI)
Throttle Position sensor (Diagnostic tool should show a value in percentage of throttle opening)
Oxygen Sensor (Hard to check this one for accuracy unless it is completely dead, best to just replace if you think faulty)
There may be an Atmospheric Sensor too. Some EFI systems use the MAP sensor to check Atmospheric pressure just before the engine starts turning over. Works out if you are at Sea Level or way up in a mountain where the air is thin
If the Coolant Temp Sensor was faulty and indicated the engine was cold it would make the bike run richer and use more fuel. Or if the wire had fallen off the Coolant Temp Sensor, but I am not sure if this would make the EFI Computer think the bike was cold, or hot, or if the EFI Computer would just turn the fault light on.
There should be a Fuel Pressure regulator in the fuel system somewhere. If that is faulty and supplying more pressure the bike will run rich. This needs to be checked with a Fuel Pressure Gauge (Old School). Some Fuel Pressure regulators have a little air hose that runs back to intake manifold, if this hose is split the regulator will see no vacuum and think you have the throttle wide open and supply more fuel pressure. This will result in more fuel used, but I think you would notice the bike a little off song if this was the case.
Any rubber boots in the intake system that may be split?
Was it a cold day? If the coolant thermostat was faulty and stuck open and the engine was running cold, the Computer would compensate and run the bike richer.
Chassis Dyno and Exhaust Gas Analyser would check the Air Fuel Ratio in the exhaust to tell you if it is running rich. I have used Innovate LC1 and Autronic Exhaust Gas Analysers with great successes in Cars and Boats but never a bike.
I have only drooled over a Fuel Injected Husaberg in the shop, so have no idea about their EFI system. I have wired up a few Autronic EFI Systems in Cards and Boats