Alex Reed

When I ride my bike on uneven terrain, I worry about the bike tire getting punctured. I don't know what are the most common causes of bike tire punctures and how can I prevent them.

genejockey 

Well, in my experience, there are 3 or 4 kinds of flats that I get.

One is pinch flats, aka Snakebites. You get those when you hit a rock or pothole that pinches the tire and the tube between a hard edge and the rim. You can tell them because the tube will have two cuts right next to each other, about half a cm apart. So, avoid rocks and potholes.

Two other types are generally caused by glass on the road. One of these is a cut or slash. Glass, especially wet glass, will cut tires, right through the tread. I've had glass cut a 1" long slash in a tire that went all the way through the casing into the tube. No way to fix it. So, watch out for glass shards - mine was part of a bottle some jerk had chucked out a car window.

The other type of flat I've gotten from glass is when a tiny piece of it gets into the tire but not all the way through. Over time as the tire flexes it works its way deeper and deeper into the tire until the point is against the tube and eventually punctures it. So, again, avoid glass.

The fourth type of flat is from "Michelin Wires", little wires that come from the woven steel belts in radial tires. If car tires get worn down to the belts, the tiny wires end up on the road, where they can get picked up by your tires, and like the tiny glass shards, gradually work their way deeper and deeper into the tire till they poke into the tube and puncture it. You can't see them, so you have to live with them

Other debris can puncture tires, of course - nails, screws, all sorts of debris on the edges of roads. Some places, thorns are a problem, but not where I ride.

SO, in case you haven't done so yet, learn how to fix a flat on the side of the road, and carry a pump and/or CO2, a spare tube, and tire levers. And remember to run your fingers over the inside of the tire looking for anything that might penetrate the tube before you put in the spare and pop it, too!

EDIT: That's on the road. If you're not on a road, I can't help you. Others will know.

Frkl

This thread will almost inevitably turn into a tubeless vs tubes debate and/or a debate about whether Schwalbe Marathons are the most puncture proof tire out there.

But my approach to flats is that they cannot be prevented. Even while not riding, there is a non-zero risk of flats through slow leaks in the valve, for example. So there are things you can do to reduce the chances of getting a flat, but it will eventually happen. If you ride places that are more than convenient walking distances to bike shops, then it is worth it to lean to fix a flat, and to carry the minimal equipment necessary to do so.

noimagination

Well, "uneven terrain" can encompass different types of riding.
- rough roads - i.e. potholes, debris
- gravel roads
- light off-road riding
- bike paths that are not maintained well
- etc.

The type of flat tire caused by "uneven terrain" is usually the snakebite type that genejockey described. There are generally 3 ways to make this type of flat less likely: (a) higher pressure in your tires (it takes more force to push the tire against the tube to pinch it); (b) higher volume tires - i.e. wider tires (more room for the tire to deflect before it pinches the tube); (c) ride so as to avoid "big hits", i.e. big rocks, roots, drops, etc. at high speeds.

The problem with (a) in "uneven terrain" is that, in many cases, it decreases traction, because the contact patch (the amount of your tire in contact with the surface on which you're riding) is smaller.

You can buy wider tires, just be sure that they will fit on your bike. If you already have a high volume (wide) tire, then higher pressure can reduce the likelihood of flats, as above, but you may sacrifice some traction. How much pressure is "too much" depends on lots of factors - the surface you're riding on; your ability to control your bike in lower traction circumstances; your tolerance for flats (i.e. how much you're willing to sacrifice to prevent the occasional flat); etc. You'll have to figure that out yourself.

Riding style and experience cover (c). It's up to you how you ride, riding to avoid flats at all costs may not be very fun. In general, more experienced riders have fewer flats per mile because they are better able to recognize and avoid situations that are more likely to cause a flat. Riding more (and paying attention) is the prescription for (c).

Another way to reduce the "worry" is, as mentioned by Frkl, to learn how to fix a flat on the road/trail. A flat is not the end of the world. If you carry a spare tube and a pump, then when you get a flat you simply fix it. If you carry a patch kit, that can reduce your worry about multiple flats on one ride. Fixing a flat can be an annoying chore (my Dad taught me how to fix one when I was about 7 years old, and I've been doing it ever since), but with practice you can do it in a few (15-ish) minutes. Some people pride themselves on doing it more quickly, but in actual fact it takes time to stop, shift the chain to big-small (biggest chainring, smallest cog), remove the wheel, remove the tire and tube, identify the cause of the flat (if a snakebite, it may be obvious so this step can sometimes be skipped), get out your tube and pump, replace the tube, pump up your tire, press any remaining air out of the flat tube, pack away the punctured tube and any tools you may have used, pack away your pump, shift back down to a reasonable gear and get going again.

shelbyfv

Yep, you can conquer this anxiety by learning to repair a puncture.

freeranger

Ya beat me to it!!

shelbyfv

Actually post #4 beat us both but it was tl;dr

jgwilliams

Where I live we have little shards of flint that perform the same function as the little shards of glass mentioned by Genejockey. Pretty much impossible to avoid, so I find that it's a good idea to regularly checking for flints working their way into the tyre . Because they are light in colour, I find that wiping over the surface with a damp cloth will tend to show them up.

skidder

Besides learning to fix a flat and carrying the right tools/parts to do it on the roadside, use puncture-resistant tires. They won't prevent flats, but will help reduce the number of flats.

CAT7RDR

If flats are a persistent problem, you need a more robust tire like a touring tire instead of a road tire.
There are dozens on the market. You will pay a weight penalty but I like the Schwalbe Marathon Green Guard for my all purpose bike.
No flats in over two years and I ride over all kinds of $#!^ that could cause flats.

PeteHski

I’ve managed to get to the point where flats are a once in 20,000 km occurrence. Just from moving to wider 30 mm tubeless tyres with sealant at lower pressure. Not even using reinforced tyres, just premium road racing tyres like GP5000S TR.

I carry a Dynaplug kit, mini-pump and a spare tube on longer rides, but I’ve never had to use it. I did have to use the Dynaplug kit once in 2022.

jaxgtr

I used to worry about this stuff, then just realized it part of the deal that flats happen, it sucks, but once I stopped worrying about it, my rides became much more fun.

79pmooney

Another "trick" that reduces flats a lot - don't ride too close ti the edge of the road. Cars blow debris aside. To 3-5 feet to the right of their tire tracks. (More there traffic speeds are higher.) Beyond that is where the vast majority of glass, debris and tire wires hang out. If you keep your ties on the clean pavement to the right of that, far fewer flats. Also cars tend to hug the insides of turns so that clear pavement is further from the curb on left hand bends and often right to very close on right hand bends. On roads you ride a lot, you will see consistent patterns.

The "how do you deal with traffic" and visibility are for different threads and I won't go there.

ofajen

What type of terrain are you (the OP) riding on? If you use tires suited to the surface, learn to fix a flat and carry what you need, then there should be no reason to worry.

ScottCommutes

Welcome to the club - cyclists have worried about tire punctures since pneumatic tires were invented in 1888.

Uneven terrain is not high on my list of worries about flat tires. Depending on your bike, uneven terrain is perhaps rocks/roots, gravel, cobblestones, bad roads? I don't think any of these are responsible for the majority of flat tires.

GamblerGORD53

I'm good at spotting nails and screws.

WaveyGravey

Keep tires properly inflated. Also, my bikes are equipped with Gatorskin tires. Flats are no longer much of a problem.

rumrunn6

avoid thumb tacks

carry some stuff to change a tube or patch a puncture. watch some videos about how to do it. even if you can't or don't want to, maybe a passerby who knows how, will help you

Iride01 

I wouldn't worry about the uneven terrain for flats. If you get a flat because of the uneven terrain, then you must have tubed tires and are not inflating them enough to keep the rim from pinching the tube between it and the tire.

It's normal for the thin butyl tubes to leak down in just a few days. So check your tire pressure often till you know what rate yours leak down at. Latex tubes are even faster. Both for rolling resistance (good) and for losing air (bad).

Welcome to BF!

indyfabz

+1. Sometimes I get a little anxious if I’m touring in nowhereville and start out on a unfamiliar, unpaved section of road, but that generally goes away quickly, especially if there are other things to worry about, like making it up the next climb without losing traction. The real concern is not a flat but rather seriously the tire.

wheelreason

I hate when that happens!...

Smaug1

↑ Excellent post.

I will add that for the bolded ones, you can often avoid these by checking your tires frequently. That's a pain, but not as much of a pain as dealing with a flat out on the road.

I went for a ride with two other riders through my medium sized cities. Awful road and he had a high performance (light, thin) road tire. He got a flat. Changed the tube, and checked the inside of the tire and found nothing. I asked him to hold on a sec and checked the OUTSIDE of the tire. Good thing the light was good; I found two tiny pieces of glass barely bigger than dust right in the center of the tire. Popped those out with my fingernail. He would have flatted again otherwise.

Thorns and goat heads are the main causes of flats offroad, and maybe sharp rocks if you're really hardcore.

genejockey 

Scrood.

79pmooney

That doesn't have to be a big deal. On a tubed tires, a dollar bill will work just fine as a boot you get you home. Then glue on a patch of sturdy fabric. (Real sailcloth from a sailmaker is excellent. Ask for fabric for small dinghy sails.) Glue an oversized patch on with contractor's contact cement. Replace tire at the usual time (ie your definition of "dead").

I make it a point to always have at least 5 bills (of any domination) in my cycling wallet. It is impressive how big a casing rip can be ridden with enough bills and all I've used have survived, then spent. (One trick, seat the bill ends under the beads on both sides to resist pressure and bulging out the cut.)

veganbikes

The best way to help prevent a flat is make sure you have a good tire that is properly installed, properly inflated and generally you will be fine. Once you know how to replace a tube it will help greatly and if you then carry the necessary equipment to change the flat (tire levers, new tube, inflation) you will be good. I also recommend having a spare tube as well. There are more than enough people who have replace a tube and have no backup and are like well I can just "blah blah blah" and I say well what if "blah blah blah" doesn't exist or isn't available or you are too far out or something else what do you do. I find having a couple tubes is handy. I generally take on on the ride and the second one at home or if it is a longer ride I might bring both.

You can get other flats from nails and glass and other detritus and that cannot always be prevented but if you are spatially aware and try and avoid that stuff when you can it will help.

What I might recommend is in the comfort of your own home in a nice comfortable chair or couch or area practice taking out the tube and putting one back in and reinflating as you would need to on the road maybe if your pump is gauge less put your floor pump on it as you finish and think it is good to see where you are at and if you need to add more add more and feel and redo it a few times. Help get the muscle memory so when you go to do it on the road in rain or cold or whatever you are better prepared. Once you take off the front and rear wheels a couple times and do a few mock flats you will be better off and if you need to maybe take a piece of paper write down the steps and carry it in your seatbag or SWAT or frame bag or whatever you might be carrying tube and tools in.