GG, I've just done 4,500 kilometres on TKC80 tyres. My 1100 is running at or just under the gross vehicle mass (GVM) as stated in the handbook.
My extrapolation from what I've done and what I see on the tyres, is that they will see about 7,000 to 9,000 kilometres depending on the surface ridden over.
One weekend, which was in the mountains, and 1,000 Klm's of abrasive non skid surface, really wore the tyres quite markedly. The bike was totally loaded to the legal limit but it still handled remarkably well, considering that the weather was running a temperature in the 30 to 37C ambient range.
My guestimation, is that about 10,000 kilometres or 6,000 miles is an absolute maximum you'll see, it does however need for you to remember how close to the GVM you are running as this will definitely shorten or lengthen the tyre life.
I've seen one set of tyres that have come from Central Australia that had done 12,000 kilometres with a fairly heavily loaded 1100. This included some high speed bitumen riding in the Northern Territory where there is no speed limit at all, allowing him to ride at 160Kph for about 2 hours non stop at extremely high temperatures. That rideing started the blocks to melt and shred a bit, so he slowed down.
I and the owner estimated that about 40% was dirt roads, sand etc, etc, whilst the rest was bitumen. However to say his tyres were shagged would be a gross under estimation, they were really stuffed!
