With so many varied numbers, I thought I should chime in as well!
Been using a FZ100 with auto for last 4 years as my daily driver. Consumption for both 80 series n 100 series using same engine should be reasonably close.
Usual consumption around town is 4-4.5km/l, a very light foot may sometime show something closer to 5km/l.
Motorway (constant 120-125kmph) gives around 5.5-6km/l. GT road travel (95-105kmph) gives around 7kmpl.
BKs figure of 8km/l at 85kmph on motorway may be a possibilty, though I have never driven at 85kmph on motorway.
BKs, what diffs does your TLC run, 1500rpm with 85kmph means a very fast diff, what tyre size/ diff/ gear box are you running?