Wow, at least you made it out of it with out going down. Looks like it might have been a piece of angle iron or something. 65 mph and a flat rear tire is not my idea of fun. Did you need a crowbar to remove your butt from the seat when you got off it?
ah, another in the list of Captains, including myself, that could easily seek out otherwise harmless objects that could cause the POS Metzler to open up and spill its guts.
After 2 flats on the Metz and numerous other issues (poor wet traction, poor braking performance, etc.) I went darkside with no problems in the 2+ yrs and 23k+ miles since.
Glad that you held it up and made it through safely.
That's an almost brand new tyre!!! Similar thing happend to me a while back just 2 days after fitting a new Metz (my last ever) - ran over a dyna bolt; loud pop and instant deflate at about 60km/h (40mph). Couldn't believe it. Front must have kicked it up and I hit it at exactly the right (wrong) angle. Very interesting stopping experience. Glad you got through it. Been on Avon ever since.