[Bike...and Dennis]

It is odd how the hairline split seems to run over the edge off the main tread. How deep is that cut? It doesn't look nearly as deep as the tread grooves.

 

[Bike...and Dennis]

It's about the thickness of a newspaper page. The angle of the split does look like it's peeling at that thickness. We have had some extreme heat on the tarmac lately and I wonder whether that could be a factor too.

Extreme heat?

Daytime air temps here run above 100 degrees Fahrenheit for over four months straight. By mid-summer, our roads are getting pretty toasty. It doesn't seem to cause tire problems.

 

[Bike...and Dennis]

Norm.
Maybe Bridgestones next time?

You get the same drivel from Bridgestone.