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I ask this out of mere curiosity. People are talking about getting punctures as if it were something obvious to get. I've ridden well over 100 000km in my life and I've never gotten a puncture. But I did, but only because I tend to let the rear tire wear out until it simply blows up.

Roads in switzerland are a charm. There is no such thing as a pothole here. Nails, glass, debris... it just doesn't exist. But everyone else around is carrying spare tubes and a pump on the bike. I know I don't.

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  • What do you mean by 100k? 100km?100 000km? The latter makes sense if you wear out tyres but you'd need to be very lucky even with the toughest tyres in most places.
    – Chris H
    Jan 18, 2017 at 17:16
  • You should go to the French-speaking side. For some reason their roads are in much worse shape.
    – ojs
    Jan 18, 2017 at 17:25
  • Some places people deliberately smash bottles and throw tacks in bike lanes to mess with cyclists.
    – Rider_X
    Jan 18, 2017 at 17:41
  • 100k is less than what some people ride in a day so riding that in a lifetime is hardly something to crow about - although Chris H kindly suggests maybe you meant 100,000 km...
    – RoboKaren
    Jan 18, 2017 at 19:00
  • Statiscally speaking you're probably just an outlier. It happens.
    – stijn
    Jan 18, 2017 at 19:10

1 Answer 1

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Punctures have three main causes

  1. Something penetrates the tyre/tube and lets the air out. Any road debris can cause punctures, from sharp rocks to nails/staples/screws. Bits of wire seem to be common, as do small flakes of glass from bottles. Its unusual to find safety glass as the cause. Fix: don't ride through junk on the road. patches of gravel should be avoided too.

    1b. Spoke ends can cause punctures this way too, if your rim strip is thin and worn or moved or missing. These are obvious because the hole is on the inside of the tube, respective to the valve stem. Fix: file any poke-out bits of spoke flat, and replace the rim strip. The cheap fix is to wrap 2-3 layers of masking tape between the spoke ends and the tube and poke a hole for the valve.

  2. Something wears a hole in the tube/tyre and lets the air out. A hole in a tyre can allow the tube to bulge out and make regular contact with the road and wear off. Fix: replace the tyre, or patch the tyre on the inside as a temp fix.

  3. Something cuts the tube/tyre and.... lets the air out. Pinch flats from running too-low pressure, sharp-edged potholes in the roadway, or railway/tram rails. Also a poorly-installed tube that gets pinched between tyre and rim. Fix: run your tubes at a better pressure, and stop riding off kerbs/curbs and through potholes. Learn to jump minor things that show up in your path.

There are some minor causes too but I wouldn't class these as punctures.

  • Burping a tubeless tyre, where the tyre and rim separate and lose pressure
  • Valve faults, where the fill mechanism fails to retain the air
  • Blowouts through over-inflation, you've added too much air and the whole tube pops like a balloon.
  • Slow deflation due to micro air leaks
  • Slow deflation due to age and breakdowns of the tube material

Wet Weather makes punctures slightly more common too - because rain moves the debris around on the road and more likely to be poking up.

Worn tyres don't cause punctures but a worn rolling surface doesn't offer as much resistance to sharp things as a thicker new tyre.

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    Regarding wet weather, I believe there is also be a small increase in the chance of sharp debris actually penetrating the tyre, as water can act as a lubricant.
    – Penguino
    Jan 18, 2017 at 21:26
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    @Penguino - Yep, I've seen the same effect, particularly with tiny glass shards. Jan 18, 2017 at 23:57
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    worn tyres might not directly cause punctures, but they allow the tube to wear down and at some point there's a hole in both. Tubes are also less puncture-resistant than tyres, so every hole in the tyre is a likely puncture site.
    – Móż
    Jan 19, 2017 at 2:29
  • If water acts as a lubricant wouldn't the debris be sliding off the tire instead of drilling its way inside?
    – AzulShiva
    May 12, 2017 at 16:44
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    @AzulShiva you'd think so - but water does two bad things - it tends to stick small objects to the tyre so they have several chances/revolutions to penetrate. And once the object has started embedding, the moisture helps lubricate the sides of the hole, and overcoming resistance so allowing the object to penetrate easier.
    – Criggie
    May 12, 2017 at 21:37

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