When I raced yesterday I pumped my tyres to 40PSI (cross tyres 700c) that was too hard, so I let out more and went by feel, must have been about 25/30.But after the race they felt rock hard.Why for this happen?

strength lost in hands from cold and exertion so they ‘felt’ hard but weren’t?

Going so fast you warmed up the tyres and increased the air pressure?

Braking too much and you warmed up the rims and thus air in tyres?

😉

Number two I reckon.

Probably that the rubber lost flexibility as the temperature of the tyre dropped. No change in pressure, just a change in compliance.

I was thinking it was a compound issue. These were wire jobs so do you reckon better quality tyres or tubs would have behaved better?