Ssevy,
Not my ride, just my 'bike, but I have done an SS1600 km on the Tiger some years ago.
Of course, one doesn't just jump on and ride 'silly' distances without setting up the 'bike, and conditioning oneself to these longer saddle times.
Bike: adjusting footpeg heights (thanks Mustang), seat covers (sheepskin and/or Airhawk), throttle lock, electronics (GPS, two-way radio, 'phone connections), etc.;
Self: working up to longer distances, maximising fuel range (i.e. fewer non-essential stops), avoiding caffeine & alcohol beforehand, and then getting used to recognising fatigue, and what to do about it (be it a coffee break, or a 20/30 minute 'power nap' - or pull the pin on the ride!).
As I couldn't get the fuel consumption down low enough on the Tiger, I acquired another 'bike for LD use, and have since done an SS2000 km ride in 24 hours - that's my limit, couldn't do it now 'tho!
Bill