I bought 3 spare tubes 3 years ago and still have one in the saddle bag 13,000 miles later.
You probably just jinxed yourself. I was bragging how I hadn't had a puncture in 8k miles and just spent $40 on tubes and CO2 cartridges in the past few days. First my latex tube experiment
went bad. Then I picked up a tiny shard of glass which I couldn't spot at dusk on the side of the road. So I got flats on two consecutive rides.
