Sunday, June 22, 2008

Tyre Damage : Continental GP4000

Can anyone identify this tyre damage or possible flaw?

This Continental GP4000 tyre has done about 200 road miles at 120psi on the rear of my bike. I weigh about 190lb.

I noticed this after climbing a local hill which has been recently relaid. At the time I noted to myself that the blacktop seemed to incorporate a lot of what appeared to be glass granules, about the same sort of size / appearance as glass from a broken windscreen. The glass definitely appears to be a part of the surface, not just pressed in by traffic.

I don't normally ruminate about the composition of road surfaces, but in the last couple of days I had been listening to an article on NPR which stated that low grade glass is recycled for road surfaces ...
So anyway, at a coffee stop, not a mile from the hill, I happened to notice these rather odd pock-marks, rather as if a miniature ice-cream scoop had gouged out the tyre compound. The cut seems very clean.

Now I can't say for certain that this had only just happened, but I had just checked / adjusted my spoke tension / wheel trueness just a couple of days before and hadn't noticed any damage.

Does anyone have a clue what's happened?

Otherwise, I love these Contis. And yes, I can spell tyre ;-)