[fian]

I have experienced a roofing nail puncture as a cyclist. In Australia roofing nails usually are galvanised with a washer to spread the load held by the head across a corrugated sheet of steel or plastic.

I was riding at around 35 km/hr and believe my rear tyre rolled along the nail from point to head until the tyre hit the washer. The washer then then forced the point of the nail upwards into my tyre, tube and then right through my aluminium rim. There was a very load bang and an near instantaneous loss of tyre pressure. I was lucky it was the rear wheel and not the front so I could keep the bike straight and slow down safely. The wheel wasn't ride-able after that.

In my car the two times I've had puncture were due to roofing screws which also have a built in washer type flange. Again I think the washer/flange acts as a lever helping to flip the point upwards into the tyre. In both cases the car tyre didn't deflate but we could hear the screw hitting the road on every tyre revolution so drove straight to the nearest tyre repair shop to get it fixed.

[code_duck]

I just got one of those stuck in my sandal a couple of days ago - presumably from construction next door. Thank goodness they have thick soles. It is basically the worst how they’re weighted and shaped in a way that makes them stand straight up.

[jimmux]

My car tyre punctures have typically been the same culprits. I hope the clowns who like to spread tarred tacks on bicycle paths never clue into how effective they are.