My ST2 mostly standard apart from cans, chip and 14 tooth sprocket does about the same (about 140-150 miles between fill ups).
But what's a fill up? Being a wuss who doesn't like pushing bikes to petrol stations I always fill mine as soon as I'm able to once the low fuel light comes on. I usually put about 15 - 16 litres in once the light shows (I know, I know, I've still got 4 to 5 litres left when I fill up which is loads for a 996 pilot) so 140 divided by 15 or 16 is about 8 to 9 ish miles per litre.
It's in the same ball park so pipes, chips and smaller sprockets don't seem to make much difference
Best achieved with my ST4S (performance cans) was 220 miles on a full tank during return trip from Mugello to UK. Also managed Plymouth to Birmingham (M42 services) over 200 miles.
ST4S, lowered gearing, performance cans, TFI injection gizmo, lightened flywheel and me behind the handlebars ..... max I've seen is 158 Plymouth to somewhere on the M5 at a "sensible" cruising speed! Then again, I was getting 145 miles per tank out of it blatting around the mountains in Spain. As long as there's enough in it to get me to the next fuel stop I'm not that fussy. If I wanted fuel economy I'd buy a diesel powered Enfield!
Yeah...I think mines about 140 miles between fill ups...I dont really check properly just guessstimate...sometimes it costs me 11 squid sometimes 14... I still dont really know how far I can let it ride on empty light. I will probably only let it do about 20-30 odd miles from the light coming on.
ST4, cored cans, 14 tooth front sprocket. I regularly get 170 miles before the light comes on. In France last year i think we averaged 55mpg thats two up, full panniers and a full tankbag.