rodneybrown,
I had a very similar experience with a Metzler MZE3 a few years ago on my GSX R600.
I went to the tyre shop to throw a new Donut on the back and the guy says......... So you're down to the second layer of tread! Yeah I said I know it's the steel tread!
I noticed a shiny bit here and there after a ride and sure nuff it was the steel belt. :razz:
Davem