WTF
Hadn't thought about using km or milage as a change criteria

Wirh my 1st mistress, Morissa, a 2006R3 (non of all these variants at time), I asked my bud and mentor (in QC, back in 2012, you had to have a mentor for 11 months of learners' permit - started my 11 months on an old Honda 750 Magna, finished last 2 months and passed my permit on Morissa), how long he kept his tires. So he says to me "I wear mine down to the ropes." (actual expression in French "j'use jusqu'à la corde", translated to English would be "down to the bone").
A couple of months into the summer and my rear has about 1" wide of steel belts showing. We're on a hot summer ride, stopped for an ice cream cone, butts on curb, and I figure I'll ask him for a more precise answer: "... so how much down "to the ropes" do you actually go on your tires?"
"What do you mean?" he asks. So I show him, and he yells "What are you crazy? It was a figure of speech!!"
Well it wasn't clear in my mind, and riding down to the first steel belt was no issue and performed fine. Now I change my Metzellers at about 2mm of tread, I think.
This is a true story and I'm not saying you should do as I did, but it is reassuring at how well built rear Metzeler tires are made for R3s.
It still bothers me to waste 2mm of tread plus, the rubber to the 1st belt plus the 1st belt. But if someday you find yourself living in a post apocalyptic world like MadMax, well at least now you can say that at least you're now "in the know", (at least for rear Metzelers).
REAL environmentalists don't like to waste. Smart environmentalists know tires can be (some actually are) recycled. In a world where "smart" recycling isn't that present, not being "real" is hard. I still have think the fiest steel belt is a good criteria, just ride as if you're in the 'great white north" = carefully, and save (the environment).
Luvyall
CrazyX

(xian)