Puncture Resistant Bike Tires From Old Seatbelts


[Nicolás] often rides his bike in the city, and on more than one occasion has ended up with a flat tire. A flat tire might not sound like a big deal, but imagine if you are a few miles from your destination and running late – now your day has gone from bad to worse.

He was contemplating how he might protect his bike’s tires from being punctured by glass and other debris, when he came across some old car seat belts that used to serve as straps for various messenger bags. He pulled the tires off his bike and after removing the inner tubes, he unrolled the seat belts inside the wheels. The belts were cut to size, then the tubes were reinserted into the wheels and inflated as normal.

He hasn’t run into any glass shards just yet, but [Nicolás] is betting that the reinforced nylon mesh of the seat belts will keep his tubes safe whenever he does.

[via Make]

71 thoughts on “Puncture Resistant Bike Tires From Old Seatbelts

  1. nothing new, but interesting choice of material. most places that sell bikes have protective liners that are inserted the same way described in the article. I am a heavy rider and same treatment on my tires has resulted in no flats for several years now. and if you live in new orleans, you know the condition of the roads there =)

  2. Hey, years back, l was stuck in the (one of the) armpits of the earth- Pendleton, 0regon.This place was probably one of the planet’s test facilities for noxious flora (and then some). My bike was given the task of the usual too early, and too late few miles from home and my armpit job. l have no idea what this certain bicycle-specific piece of plant design was really called, but we just called them ‘goat heads’. for their particular tank trap design par excellance. each and every day, when it was time to go home, l pumped up another puncture,to be fixed at home after work. Before that, l never had any idea just how many patches could be put on a tube. Kinda looked like leprosy after awhile

    1. Goatheads (and that is what most from Southern California to Texas call them) are NASTY! They are proof that nature can build an armored micro-sticker capable of punching through Kevlar on a whim! Believe it or not, after TONS of failures from Tuffy liners to Rhinodillo liners, I made my own that actually worked! The problem is the plastic they use. All the liners are using Urethane. Forget that, use PET (Polyethylene). Simply go to the store, buy 1-qty 2-liter soda per tire you need a liner in. Make sure the soda is a flat-wall bottle, like a Pepsi or Mt. Dew (sorry, Coke won’t work on this one). Now, cut the top off and bottom off, until all you have is a straight cylinder of plastic. Now, take a marker and draw a spiral line around the bottle – I use a compass, so my width stays standard as I spiral around the bottle body. You can get a strip out to about 85-inches (around 28…maybe 29″ diameter tire) out of one bottle. Now, make sure you use some 200-grit sandpaper and knock all those edges down, so they don’t pinch or cut the tube. Then, just put them into the tire and re-assemble. Costs $10 less than a commercial liner, 10x tougher than any liner you can buy, no significant weight gain on the bike, and I personally can’t tell a lot of ‘harder ride’ quality either. I have YET to have a goathead puncture this liner!

  3. Yeah we have goat heads down in New Mexico and they will easily puncture not only a bike tire but, small trailer tires and 4 wheeler tires, that green slime works wonders.

  4. I wonder if you could use some sort of metal mesh, like chain maille. The downside would be if THAT had a problem, it would probably do the puncturing of your tire from the inside.

    Slime is awful if you don’t ride for a while and it all settles in one spot.

  5. This might work, but increasing the rotational mass of your wheels increases the work required to ride, especially during acceleration. I imagine the off the shelf options would be more efficient.

  6. I got a flat because of a screw once, then repaired the inner tube and got at least 5 other flats because I didn’t repair the tire itself. In the end I just cut a piece of an old tire and put it over the hole: fixed forever.

  7. Slime is bad, I know first hand. It dries up too fast in one spot, and doesn’t really work that well. The yellow stuff you get for car tires is much better, as it fills the hole and solidifies, and it doesn’t dry out over time inside the tube.

    I wish I had seat belts to do this with, then I wouldn’t have had to double up on inner tubes, or waste my money on those extremely crappy sponge tubes, the “never get a flat again” pieces of crap.

  8. I dont understand the application. Debris would be coming in from the outside of the tire, not the inside. These straps are placed inside the wheel… shouldnt they be placed inside the tire?
    o.O confused…

  9. I’m impressed, it’s a terrible solution.

    A thorn will go through that easily, so will debris, a nail and eventually a glass shard.

    I’m assuming you won’t care about the added rotational inertia, or the fact that it could potentially get wet and ruin you’re ride, (the tyre-rim assembly is not air or watertight).

    Get a proper tyre, or at least do it with a Kevlar strip.

  10. Sigh. This is a classic example of people reinventing the wheel, pardon the pun. The biggest problem with this solution? Astronomical rolling resistance.

    Bike tires come in a variety of levels of protection. The tougher ones have thicker treads and/or kevlar linings built-in.

    You can also get thicker tubes, as well as puncture protective linings, and yes, “slime” that goes in the tube.

    If you keep getting punctures, you’re:
    a)Not running enough tire pressure (do you get a pair of punctures? This is from the tire bottoming out and getting cut by the rim, also called a “pinch flat”)

    b)Running too much tire pressure (in general, or for your weight.) If you’re on the heavy side, you should be running a wider tire, so you can thusly run a lower tire pressure. Why? The higher the tire pressure, the higher the force pushing the debris, whatever it is, against the tire. If you’re running 80PSI, that’s much less force pushing a piece of glass against the tread than if you’re running 120.

    If you google around, you can find size and pressure recommendations on some of the manufacturer websites (Schwalbe, Michellin, etc.)

    Lastly: if you have a normal chain-driven, derailleur bike…flats are no big deal. Bicycle tubes are actually quite easy to change out, and patch kits are super cheap. I carry in a small bag the lever, patches, and spare tube. In my pannier bag goes a pump (my road bike has a pump mounted to the frame.)

  11. @B

    what he’s done here isn’t re-inventing the wheel, it’s using stuff you’ve got lying around to solve a problem… aka hacking.

    the fact is that there are many debris on the road, particularly in cities, that will have no problem puncturing a tyre, even one at the perfect pressure… the advice you’ve given is relevant advice for someone who often gets punctures, but is by no means an alternative to a solution like this… also, yes there will be problems with additional rolling resistance, but to be honest, a consistent moderate problem slowing you down is far easier to deal with than getting a puncture 1 day in 10.

    rant over…

    nice idea though

  12. The real fix? Use a good tire with a kevlar belt, and slime tubes. Yes, critics say a slime tube will still leak a bit. However, in my opinion, a slime tube’s purpose is to limp you home once it’s punctured.

  13. Although the idea is cheap and clever I have to agree with ‘B’ that its not ideal.

    I used to be a cycle courier in the city and simply buying fairly cheap (£30/pair) slick, narrow, kevlar lined tyres for my mtb saved many many punctures and kept me whizzing round the streets. In fact some evenings would be spent picking the glass out of the tread.

    Adding rolling resistance is a big deal if you want to be an efficient cyclist. On pure tarmac roads you are looking to reduce the weight of rims, tyres and tubes along with having a high tyre pressure and narrow tread as possible.

  14. one other thing to remeber is most times when a sharp thing is going to puncture your tire, it’s the second time around that does the damage.
    At the bike shop I used to work, we sold these groovy things called “nail pullers”.
    All they were was a loop of stiff wire that mounted on the brake calliper pivot.

    So simple, yet so effective!

  15. I could’ve done with that hack a week ago, on one of my night rides I got a puncture and had to walk back 3 miles to home, luckily the weather was pleasant but that didn’t stop my feet from complaining.

    The green shit in the tube didn’t help one bit, somehow a previous puncture in the innertube had opened up to 1cm long and the entire inside of the tyre was horribly slimy, the green shit then hampered the business of putting patches on as there were more than one hole that needed to be fixed.

    The seatbelt idea is perfect, the added weight would not hamper the ride experience as it’s an electric bike which weighs significantly more than normal bikes, and you don’t notice the extra weight when riding anyway.

  16. Seconded on the Wire Loop “crud skimmers. They really “just work” for what they do.

    Slime’s a mitigation not a cure. It’s a make-do method of adding one more graceful failure mode. The layered approach of skimmer loops+some sort of Kevlar tire+an inner liner+Slime or similar flowable gunk all combines as “Risk Reduction” so to speak.

    The excellent hack of seatbelt material is worth some exploration as it’s “Good Enough” of a concept to warrant larger scale trials. Lest we forget- there are a LOT of folks in wheelchairs that use bike tires! They might be helped by this hack too.

  17. Too bad only a few people will ever read this.. Many years ago I was replacing my inner tube and the only one the store had was “thorn resistant” to which I had to state “thorn resistant!?!? I’ve never hit a thorn and had it puncture the tire, much less the inner tube. I bought it despite the higher price and put it on my bike. Less than a week later, It proved NOT to be resistant to the 3-inch long “jesus thorns”(they look like a cross, no joke) that I ran into for the very first time. This left me stranded just as it would have if I’d bought a normal inner tube so I’m guessing I was not pleased since on top of it all, I’d used my last patch on the previous inner tube and the store was out of them when I bought the inner tube and I wasn’t expecting a flat….from a thorn..within a week…

  18. If someone does read this, could you explain how kevlar is supposed to prevent punctures? I know enough about kevlar from personal experience to know 1)that it can easily be cut, so glass would most definitely affect it, and 2)that kevlar vests stop bullets but they do NOT stop knives, broken bottles, probably ice picks, etc. since they’re a different kind of force being applied. So how does that work?

  19. Ok..First, this idea won’t do jack all…beyond adding a little depth, thus reducing damage from shorter barbs. It MIGHT add some amount of slash resistance, but it’s a woven fiber that isn’t that tight. It has just about no protection against punctures…To see this yourself, get a thumbtack. Go out to your closest car. Figure out what to do with the thumbtack yourself. Doesn’t take much pressure, does it?

    As for the Kevlar question, HOW Kevlar is woven decides wither it is slash or puncture resistant. They make slash resistant gloves out of Kevlar for fishmongers, and puncture resistant gloves for cops…and combinations therein. Remember, the key word is RESISTANT. Enough pressure, and you can cut through just about any material.

  20. When I was a lad and neither pocket-money nor parent would afford the replacement of a thread-bare tyre, we used to cut strips of PVC off ice-cream containers and sandwich them betwixt tube and un-tyre. Aint nothin’ getting through that.

  21. I had to repair a flat on my little brother’s bike today. It wasn’t set up like this guy’s tire though. All I did was take a latex glove (that I stole from the doctor’s office a few days ago) and cut it into a rectangle. Then I super glued over the hole and wrapped it with the latex while adding more superglue. And to finish it all off I wrapped the entire “bandage” with electrical tape. He’s pretty rough on his bike, and after the patch it hasn’t lost any pressure.

  22. @zacdee16

    Super glue? Like…cyanoacrylate, regular crusty old super glue? I’d guess that it will harden and flake off in short order…that’s why they have patch glue.

    Anyway…in Cali we have what I’ve always called ‘demon vine’ which sounds a lot like goat thorns. They grow in little clusters of several ‘heads’ with two long thorns each along with a bunch of spines. They’re only about the size of a pea, but they make a mess of tires. And shoes. And bare feet.

    I’m a bare-footer when I get the chance (I walked across our Sacramento area parking lot in bare feet in the sun yesterday. It hurt, but not too bad.) I once walked barefoot into a patch of dried demon thorns, which I mistook for a dusty patch of driveway. Even after pulling out the majority of the thorns, I still had to go back the next day with tweezers to get the remaining spine tips that broke off under the skin. o.O

  23. Punctures will always happen. The two best hacks which deal with them are:

    1. Get a better tyre. From experience, I went from an average of a puncture every 2 weeks to not having one for 8,000 miles just by changing tyre type. Not sure the seat belts will top that.

    2. Always carry a spare tube + pump. A lot less hassle than having to walk home. Same as buying components – if you need 2, buy 3 just in case.

  24. Used to do this as a kid with Duct Tape. Couple layers on the inside and you could ride the dunes forever where there was all manners of broken glass, rocks and thorns.

  25. Aren’t seatbelts designed to be cut easily? I always get intrusive thoughts of my car crashing and exploding in a ball of flames. I pacify my self with the idea it’d be easy to get out of…

  26. Where I live most tires come in a very cheap variety and a normal one (still not that expensive) that have a kevlar puncture-prevention layer.
    Seems that is the standard so perhaps he should get those instead.

  27. Didn’t read to see if anyone else had this idea – but this would also come in handy when you’re using bolts/screws to make your own winter/ice bike tires (or other high traction use tires).

    I converted an old tire with metal screws (over a hundred per tire) a while ago into a winter tire and used two layers of duct tape. it worked okay, but i noticed wear after 1 season’s use on the innertube. This would probably work better than duct tape for that application…

    by the way, the converted tires worked amazingly, but the crappy rubber pad on rim friction brakes suck when frozen and/or wet. snowbanks quickly became my braking system…

  28. An old tube works better. I’m the mechanic at my local bike shop and I’ve seen a few locals try some methods like these. Some companies actually make what’s called a tireboot, it’s just a piece of rubber that sits in between the tire and tube. But with this seat belt method I’m sure you’d have a rough time seating the bead depending on the tire/rim combo. Where I’m located, I’d say about 75% of flats aren’t from punctures but from pinch flats, or snakebites. Cause by running your tires at a lower pressure. Common misconception, you’ll get more flats if you run the tire and the minimum recommended pressure as appose to running it at the maximum.

  29. Great idea as long as you are travelling short distances (like a mile or less). Other than that it’s just one of those “there, I fixed it” moments. Bikers, those who actually ride and put tlc into it, prefer lightweight components. The real key here to NOT getting a flat is to have quality rims and quality rubber. The best tires I know of are Schwalbe Marathon XR’s (approx $60ea and worth every penny). The standard $5 tube is plenty sufficient with these tires. Slime? Garbage, as it’s used with cheap sellers to prevent flats with their junk rims and trash tires and will regularly plug up the valve stem and also adds more weight while at the same time causing imbalance-the bain of a tire’s life, if not the rim itself.
    In any case, ALL tires which take air will leak over time, no matter what. Other than completely redesigning wheels to use no tubes or air, in case of a ‘leak’, slime would be the simplest patch job. But like I stated, the quality of your rubber and rims, along with proper maintenance, is what keeps the bike rollin. Putting odd materials inside the wheel is asking for trouble. Though a few dynabeads may help with balance issues.

  30. @ DeadlyFoez Chev Quincymd
    MarkG B Whatnot
    John PilotGeek Zacdee16
    Drackar Cas

    Did you forget what site you came to??!!

    !HACK! A DAY…. Sujesting store bought options to a mans “on hand” hack… pretty lame and useless trolling if you ask me.

    Thanks to the ones who actually gave personal experiances and mentioned their own HACKS.

  31. got a pair of bike tires from my local decathlon sport store a couple months ago.
    they’ve got a built-in metal sheet to prevent punctures.
    seat belt won’t ever be as good as metal (against thorns at least), but I guess it’s a good compromise

  32. @ehrichweiss

    kevlar doesn’t make punctures impossible. Bicycle tyres are generally fairly lightweight so there is only a small amount of rubber and some thread between the tube and the road. Kevlar just makes the tyre more puncture resistant without negatively affecting the tyre too much. Glass shards certainly can and will get embedded in a tyre and gradually work their way through to the tube even past kevlar.

    That’s why there are tyres like the marathon plus that uses a thick pocket of rubber to trap objects in addition to kevlar.


    Stan’s No Tubes only works at low tyre pressures suitable for off-road riding. At the higher pressures used for road riding the pressure just forces the latex sealent out of the puncture before it can seal. Instead of little white spots at the puncture site you can see on the video you get streams of latex pissing out of the tyre, shortly followed by air once all the sealent has been ejected.

  33. @G-Reg Oh shut up fool, why hack something that is already there? Use the saved time to do some real hacks
    It’s silly to desperately try to make up half-baked solutions when the fix is standard and cheap and available in every shop.
    My criteria is that a hack should either a) save money or b) do something that’s better or more tuned to your needs.

    Also don’t be one of those pathetic idiots who just call any other person they disagree with a ‘troll’, people will like you better or at least take you more serious.

    If I see someone come up with a complex and expensive and time consuming way to dremel thin slivers of a block of metal to join wood I’ll tell them they sell nail everywhere thank you very much.

  34. Hey Mr.Whatnot. I can rip your lil post to shreds from many angles but ill just pick the obvious.

    The one who chooses which post’s to publish OBVIOUSLY didnt see it so half baked. Not to mention the others who have commented on simular experiances.

    Your a tool if you honestly think the man who made this didnt know he could have spent money to fix

    Horrible analogy btw. I highy doubt his seatbelt fix was complex, expensive, or time consuming.

    So just chill out and accept your wrong and stay quiet in your conner by yourself.

  35. Single speed, lightweight aluminium frame, thick tires and all rust resistant parts.

    I have this thing for about 3 years now and i never had to adjust or repair anything; very reliable.

    Try building your own bike, it’s really not that hard.

  36. If you could get black urethane to cure without open air, a way to increase viscosity and mix under pressure with argon (very well) that would make a badass tube. The trick would be injecting the ‘foam’ into the tube and have a controlled pressure release value that let the tube reach optimum pressure and then hold until cured, excess foam could spill out into a inline purge bottle to protect the compressor and relief valve. argon:urethane ratio would control the resulting foam rubber density.

  37. @Drackar, perspectives on the table expand the creative process if they offer value. It may be a waste of time to do things a certain way from one perspective, the learning process is anything but. In the realm of hacking I’ve found commercial solutions to be a great launching pad to draw from, just tear apart some junk and excel in identifying the residual value of component’s properties, or just reengineer somthing to work better or in a different way.

    Many people cannot hack the situation so to speak, where first they might not like your perspective they could spin or take whatever value it has and build on it. From a performance perspective I found value in your comments and don’t really care one way or the other about the social crap, though I do ‘get’ the criticism, maybe you could adapt a little to grease the wheels of learning? Or not.

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