1600 Fuel Gauge Duff

Well that was fun!
Just purchased from a dealer and was surprised to see that, unlike the norm, there was a nearly full tank. (according to the gauge!)
Went for a short initial drive and thought economy was good as the gauge seemed to alter little.
Decided yesterday on a longer trip and headed out.
By now my suspicions should have been raised as the gauge still showed a substantial amount of fuel.
Cruising along the A34 the bike looses power and stops......on a busy dual carriageway!!!!!
My immediate suspicions were fuel but the gauge still showed over half full!!
Anyway, long and short was that I spent a happy hour and a bit at the side of the bust A34 waiting for my wife to bring out some fuel.

So!!
Gauge reads plenty of fuel and no low fuel warning light. Got to be the sender, yes?
Or could it be something more electronically complicated?

Oh, and don't worry, the dealer will be getting an ear bending on Tuesday!!

Cheers folks.

PS. Sorry, here's a pic of the newbie for the forum.



Replaces my 05 America which gave me years of service and never let me down!