I am on my 3rd rear k60 scout on a f800 gs.The first one was a 140 that I put on in Fairbanks that was the original tread design.It lasted about 7000 mi,had some left but changed it out a few months after I got home.Put the 2nd 140 on and it lasted about the same.Most of the miles are on gravel or offroad.Now I have the 150 on that is the newer tread and do not like it as well as the 140.The 140 is more predictable on power sliding.The 150 sometimes does weird shit in loose gravel corners.In fact I took it off when I did a ride down in Arkansas and put a new 140 on before I left.I do have the 150 back on trying to wear it out.If you get in the slimy type clay mud the k60 doesn't do so well but as a 50/50 tire it does the job.
As far as the front k60 I took it off pretty quick.Did not like it at all.Currently running a TKC on the front.
"I will not follow where the path may lead, but I will go where there is no path, and I will leave a trail". Muriel Strode,1903
2012 KTM 350 EXCF - 2008 WR250R