Why using a puncture repair kit instead of a new inner tube?

Question

I am a casual rider (~30 km commute as often as possible) in an urban setting.

Reading this SE site to learn about biking (the resource is extraordinary, even though I don't understand every technicality) I see that one of the suggestions given on a regular basis is to have a puncture repair kit.

I ride with a spare inner tube and used a kit maybe 30 years ago - I thought it was an inferior approach to just swapping the inner tube (because you need to find the hole, prepare the kit, glue etc.). I see that I was apparently wrong.

What are the reasons to recommend a kit rather than a spare inner tube?

Is it because

• of the cost? An inner tube for my casual riding is a few euros, I needed maybe one or two last year
• of the reusability? One kit probably serves several punctures but then I would consider having both - in the unlikely case I get a puncture (statistically from past years) I would use the spare, and have the kit in case of a second one.
• of the ecological considerations?
• of the weight? This is a good point but I do not feel the extra tube in my backpack over such a short distance

Answer 1

You have to remove the wheel to replace the tube. A repair can be done in the frame.

On older bikes without quick release, and with current gear hubs, electric hubs, Nuvinci hubs, belts etc, you need a spanner and oftentimes, the gear adjustment goes back different and needs fiddling with.

This reduces the advantage of tube changes. A fix is only 3 mins.

Hints:

• Once opened, small tubes of glue dry out very quick, so I always have an unopened tube in my kit.
• I also find that using the aluminium foil from the patch, over the tube opening, and screwed under the cap, keeps the glue alive longer.
• real sandpaper beats the hell out of the useless punched metal scraper thingy
• you should have a square of canvas or equivalent for covering splits in the tyre sidewall

Answer 2

I think you answered your own question to a large degree, but probably cost is the big one for most people. Once one knows what they're doing with a traditional vulcanizing patch kit, most of the time you can make the tube as good as new in a few minutes, maybe 10 minutes to be realistic but not overly optimistic. That's a reasonable time versus money proposition for most cyclists, especially once you factor in the time cost of going to buy tubes. Once you have the hang of it, you can often keep the same 3 tubes going for years using the common method of carrying a spare and a patch kit, or just the spare, using the spare first when out on a ride, then patching your punctured tube (probably while watching TV for even more time savings) when you get home and then have it become your spare.

The eco part is a reasonable consideration too for a lot of reasons, not the least of which is that butyl is a non-renewable resource and rubber goods production in general is fairly nasty.

A further upside of patch kits that can really save the day is they allow you to be prepared for repeat offender type flats, where something you fail to find and dig out is lodged in your tire and causes multiple flats, or where there's some kind of rim strip or rim problem that does the same, which tend to strike most cyclists sooner or later.

Answer 3

I'm surprised no one here has mentioned the obvious answer. I carry 1 spare tube, a patch kit, and 3 CO2 cartridges. That's all I have room for. There simply isn't room in my saddle bag for two spare tubes. On a long ride I can fix 3 flats (which implies I need a new tire). The patch kit is the last resort, but it's way smaller than a new tube, let alone an extra 2 tubes.

I do agree with others here, if I help some random stranger out with a flat I will patch their tube rather than give them my spare. The spare costs $6-$7 plus the CO2, a patch costs $.50 plus CO2.

Answer 4

Why not combine it? I usually carry both - one tube and one repair set. When I get a puncture, I use the spare tube, keep the punctured one and repair it when I get home. This has multiple advantages:

• since I have quick-release wheels, it's much faster to use a spare tube than wait for the repair
• you don't always get a puncture in nice dry weather. When it's rainy, you're tired and you have nowhere to hide, repairing a tube becomes a nightmare
• I still have the repair set in case I get two punctures during one trip
• I get the price and reusability benefit since this approach only requires one extra tube (which you'd buy eventually anyway, you can't repair it forever)
• the quality of repair is better since you have time to do it properly at home

The only disadvantage is the little extra space you need but I don't really mind since I also carry repair tools with me.

Answer 5

I personally carry a puncture repair kit to give to strangers I meet that have flats.

I carry 2 spare tubes in my side bag as I'm paranoid of running into a broken glass patch (urban area here) and having 2 flats at once. I actually gave away 3 repair kits and used only used 1 tube for myself in several years of biking to work.

I like carrying them because obviously other's won't always have the same tire size as me so it's an all-purpose stranger help kit.

Most bikers around my area aren't equipped to make a quick fix.

Answer 6

One consideration that you should think about are those rare occasions where you get some issue with a tyre that manages to puncture tubes 2 or more times in quick succession. You'll always try to ensure that the tyre is clear of the cause of the puncture, of course, but it does happens sometimes that you just can't find it.

In that case you're either replacing and throwing away several brand new inner tubes, or in worst case scenario get through all your spare inner tubes in a single ride and then get another puncture..

Like most others have said I tend to pack for worst case, so during my commuting I'm generally carrying:

• spare new inner tube;
• repair kit;
• what is now a third-generation swapsie patched up old inner tune, which I subsequently swapped with a fellow commuter who was riding with no backup and was SO happy and grateful to have me rescue him (and save from from being late for work having already been warned once) as you would not believe. I took his broken tube home, patched it, and then swapped with another rider who'd been carrying a spare tube but hadn't thought to clean the cause of his first puncture out of his tyre. His old tube is now my spare spare, patched up and ready to swap with another unlucky commuter...

That reminds me - I should probably check my repair kit and make sure I've still got plenty of patches, and that my glue hasn't dried up!

Answer 7

A piece of advise that has not been mentioned yet, but which works really well for me:

• Use the best puncture resistant tires you can get.

  From my experience, I'd estimate they got my puncture frequency way below 1 in 5000km. It's hard to say precisely, I only had about two or three punctures since, and cannot recall how much km I did in between. That's a huge difference to the one in 100km that I remember from before I switched to puncture resistant tires.

• When the reduced puncture risk is still too high for you to just deal with being stranded (like, just hob on a bus to get to work), carry a spare tube.

  At such a low puncture rate, the few dollars that you save from using a repair kit is just not worth the added hassle anymore. When I get a flat tire, I always consider the state of the tire itself to decide whether I'll replace that as well while I'm at it.

Without puncture resistant tires, you are constantly experiencing flats, and can get a lot of experience using repair kits. I most certainly did. And you certainly don't want to buy new tubes at such a high rate. So you are training to patch your tubes, and become quick at it.

This changes drastically when you change to puncture resistant. You will quickly forget the skills of using repair kits, so you'll just want to replace tubes, and you'll be happy about it...

Answer 8

Easy.

A good mini pump (such as the Quickex Quicker Pro which I have and which unfortunately isn't available for sale anymore) will pump a tire hundreds if not thousands of times. Thus, by carrying a pump instead of a CO₂ kit I'm not limiting how many flats I can fix.

A Rema Tip Top TT04 Sport kit has 6 patches. It weighs 18 grams. Thus, 3 grams per puncture.

On the other hand, a Continental 32-47 / 622 inner tube with Presta valve weighs 220 grams. Thus, 220 grams per puncture.

To have capacity for 6 punctures with the tube approach, you need 1.32 kg of tubes.

It might make sense not to obsess over bike weight but rather obsess over weight of carried equipment such as water bottle (you won't need it -- usually you can find a shop less than 10 km away from your route, so a lightweight credit card can replace a heavyweight bottle) and tubes (carry just one and replace the 5 others by a repair kit).

However, carrying one spare tube instead of 0 spare tubes and just puncture repair kit has some merit. The rubber glue will take a day to fully harden. By putting a recently replaced tube in the wheel, it has a risk of starting a slow leak. Thus, you repair the punctured tube, put the spare tube in and the recently repaired tube becomes your new spare tube. In emergencies (both wheels flat, two consequent flats) you may need to put a recently repaired tube in the wheel, thus starting a slow leak.

The saved tube replacement expense is a bonus, but not the real reason why tubes are repaired. Repairing prepares you for multiple punctures in the same day.

Answer 9

I carry a spare tyre because sometimes I can't find the piece of glass or metal that has punctured the tube. If I am sure where the puncture is, because the piece of debris embedded in the tyre is obvious, and or I can hear the leak from that point, then I can use a patch (sometimes without even dismounting the wheel).

But if not, then I change my tyre and tube and, patch the tube at home. Now that tubes have become cheaper (2USD from aliexpress) I have a backlog of un-patched tubes that I may never patch.

Without a spare tyre, then a spare tube is not a fail-safe solution because the offending piece of glass, or whatever, may only poke through to the inside of the tyre under high pressure so however many times you run your fingers over the inside of the tyre, the cause may be very difficult to find.

Patches increase your options, or available attempts.

When a patch goes well it results in a tube that is a little bit stronger than a non patched tube.

Answer 10

A kit is great if you either don't have a tube or got super unlucky and had to use the tube you already had. I look at kit as a temp fix until you can put a new tube in.