Just under 120 (indicated) (so probably 108 reality )

130 gps tracked and on the mechanical speedo

Readings taken about a month ago:
118MPH (190KMH) at night with fresh air.
I've managed to hold a little beyond 100MPH (160KPH) uphill.

Bike is an oldie '91 blue with 82000Km (51000miles) and has a 17 teeth sprocket.

(was a little faster years ago).

Did 120 mph indicated a couple of times on an empty motorway - with only about 3/4 of the throttle.  It felt as if it would go faster, maybe another 10 mph (indicated), but it was a bit too scary to try that. The tach never worked since I got the bike so I don't know what RPMs it had.  Started life as a naked E model, but then got a front fairing and a dual headlamp conversion and a Scorpion exhaust.  Everything else is stock.

I did 110.6 actual today on my way to work.  level, with slight headwind

My GS500F... ~95 mph in a burst. I never ride consistently faster then 5 over the limit here in Canada.

My bike handled much better at faster speed with the lower plastics removed. No as much cross wind messing me up.