I did a search but didn't turn up anything definitive on the practice of repairing and reusing a tire with a small puncture. I know it's best to replace it, but I'm cheap and the tire has less than 500 km on it. There is a small, perhaps 2mm cut along the bottom tread. Could it be repaired and used safely? The venerable Sheldon Brown recommended using a section of an old tire as a boot, but as a temporary fix on the side of the road.

What say you? I'd only use it on the rear wheel, needless to say.

A piece of a tyvek mailing envelope is usually all it takes. In an emergency, use a dollar bill. Tuck it between the innertube and the tire. Inspect it once the tire is inflated; if you see a bulge, you have a problem; but in most cases you won't even find the puncture.

There really isn't any way to glue the hole shut; people talk about using super glue for this purpose, but i'm not convinced it does anything.

Do you have a photo? How big of a cut through the casing down to the tube?

A 2mm cut may well be of the size that it can just be ignored. Over time you'll get more of them. Just repair the tube, and keep riding.

I did try superglue to fill holes once, and for the most part it was effective, I think. But, I periodically probe my holes for glass, and the filled holes looked like debris filled holes, so I dug out many of the filled holes.

I'd probably boot it and keep an eye on it, if I really wanted to save it.

I think I'd try something with structure (most patches are just rubber and would bulge out if unsupported), probably a bit of an old tire which would have belting in it. Cut a patch sized bit, feather the edges, and glue it in place.

Really I'd probably just write it off as bad luck and replace the tire, because my route is long enough that I don't want to be caught 20 miles from home with a completely useless tire. But if I was riding closer to home I'd maybe try the above.

got a photo of the "2mm cut along the bottom tread"?

2 mm is about the size of the typical grit puncture I tend to get.
Roadside, I have no problem at all simply ignoring it.
At home, I will try to patch/seal it one way or another as it seems like holes like that can pick up debris that'll work its way through and chafe at the tube.

Now, the commuter never sees more than 6 Bar intentionally.
Higher pressure tires may be more sensitive.

I'll try to get a pic of the cut when I get home.

It's probably a combination of my upbringing and not having the means and access to buy whatever we wanted/needed whenever we wanted/needed it, but I grew up believing that throwing things out on a whim is not a good trait - simple repairs should always be attempted. I ride on patched tubes (last one lasted over 1000 miles) because 1. it keeps it out of the landfill longer and 2. I save a few bucks.

For a tire I generally don't even bother repairing it. Just make sure you remove whatever caused the puncture, then carry on - never had a problem with the same spot again or mystery punctures. Always caused by a shard of glass or a wire bead or similar kind of sharp debris. I recently inspected my commuter tires and was amazed to see how many cuts and slashes there were in the contact area; none of them have been a problem for 6+ years I've used those tires (Maxxis Xenith)

Here's the puncture. The Canadian quarter there for size reference:

IMG_0781.jpg

Doesn't look worth worrying about. Does it go all the way through or is it just in the surface? I would make sure nothing is in the bottom of it trying to work its way through and then put a little Shoe Goo in it. Although I'm not sure that has much effect.

Put a small piece of Duct Tape on the inside of the tire and ride.

It does go all the way through, and a small piece of metal sticking out from the inside. If I decide to fix it I'll have to somehow remove that.

wonder if it would be more likely to pick something else up in there, whereas on a smooth surface, the new object would just bounce off

patching tire or not, I suspect you'll need to remove that metal anyhow, to get the tube to hold air.

I always just ignore punctures in tires. Until the tubes start getting punctured at too high a rate. I rode one big apple with a quarter inch by quarter inch flap hanging loose for another 2000 miles. (it was the first week I had the tire on; I should have gotten ~5k miles out of it)

Are Canadian quarters half the size of US quarters?

I'd just clean out the hole, and ignore it. You'll get more holes like that over time.

Possibly a radial tire wire. They are super-sharp and often impossible to find, so you're lucky to have found it. Pull it out with needle nosed pliers. If there's no damage to the cords, there's nothing more to do than to put in a new or patched tube and carry on. If one or two cords are cut, you could put some duct tape on the inside. And keep an eye on it for bulging.

They're 74.73% of the U.S. quarter...today.

That's not much damage. The key is what it looks like on the inside of the tire. There is a good chance that the puncture did not damage the casing to any significant point. Boot it as others have recommended and watch it for the next few thousand miles.

Not worth a boot unless you pump up a new tube (after removing the metal thing) and there is a little bulge there. I am happy with the Park Tool boots.

That sounds like it will cause future punctures if not taken care of. One of my tires had a similar wire sticking out the inside, and I took my Dremel with sanding drum and ground it down. I could see a couple of sparks so it was definitely not something to ignore.

Good grief, I wouldn't sweat that. Just fix the tube, pump it up and ride. Keep an eye on it to make sure it doesn't start to swell, if it does, boot it, but I bet it doesn't.

If the metal/wire didn't come as part of the tire which is unlikely, then it has to come out.

Cutting it off doesn't guarantee it won't work itself further in over time, or pressure of the tube won't expose it

Pull out the wire and carry on. If you leave the wire, you will get more tube punctures there. The damage to the tire is negligible.

Thanks for all the comments.

I pulled the wire out. Made sure there were no other sharp protrusions. Stuck a piece of cloth tape on it just to cover up the hole from the inside. Yeah, know it's rather useless, but was the only kind I had on hand.

Pumped it up to pressure last night. Seems to be fine.