Originally Posted by
acantor
On all tours, long or short, I carry a patch kit and a pump.
On a long tour, I bring a replacement inner tube. On a short tour, or if I am going out for just the day, I may or may not carry one.
But going forward, I will always bring an extra inner tube. I just experienced a rare failure: the nut on the presta valve snapped off while I was inflating the tire, which rendered the valve useless. The only solution: a new inner tube!
The moral: Unless you are OK with not being able to cycle on a cycle tour, always carry one or more replacement inner tubes.
Oddly, this is actually not that rare, especially when affixing a pump to a valve. In this case it would be well to have an extra valve core or two handy, as it's easier to put a new core in than it is to change out a tube.