I've just given my bike a 'proper' wash and have noticed this on both tyres.
You can actually feel the carcass if you run your nail along the lines. It's on both tyres, on both sides and pretty much round the whole circumference, so what do you think, keep running them or deposit them in the bin? My feeling is that if they do let go, no amount of tape, tyre boots or bodgery will get me home
Just what tyres seem to do when run tubless at lowish pressures. That or your legs generate drag racer levels of instant power and the tyres are rolling up as you accelerate.
All our race tyres look like that, Schwalbe Ralph's Ron's mainly all run tubless 26". Except for the snakeskin ones they seem to look like new. Personally wouldn't worry. We are running all Specialised tyres 29" at the moment ( nearly all s-works), they are good but are begining to loose the outside of the sidewalls the same. But we really like the fast track's, for most of the riding, most of the time it's become the tyre of choice for us for all riding I. The Peak.
A quick spin out over the hills, walkable, self rescueable, other half rescueable... I would run one on the back. Maybe / maybe not the front. Without actually having a feel, look etc myself I'll not say.
heading over the hills and far away, multi day adventures. I probably wouldnt. Especially If I was going somewhere rocky that puts sidewalls in peril.
Also, depending on their age / mileage and how low I'd been riding them I would possibly not buy again. At the least, I would up the pressure. if i bought more.
