Let down again

Whizzing along on my new bike and then the unmistakable bumpety bump sensation of a deflated tyre. The second time in a few days! Walked it back to the car - not for nothing I reflected that bicycles are also referred to as "push bikes".

Off to the shop where the expert (he can replace an inner tube in 90 seconds) took the wheel off, found the puncture but no cause, replaced the inner tube and after discussion I bought a pair of more robust tyres that are supposed to puncture only with difficulty. We'll see!