Bicycle Mechanics - The art of the puncture?

So there I was this morning, did not have to go into work until this afternoon, got up and Precious and I went for a ride. Precious got three flats. The first one I just changed the tube and went about my business. The second I tried to find the puncture and could not. I refilled the tube I figured I had screwed something up when I fixed the first flat (left the valve open or something). The third time I gave up and walked home.

The question: Is there an art to finding punctures?

I usually fill up the tube, give it a first pass by making a donut w/ my fingers and going around the tube once. If that doesn't work, I try running the tube by my upper lip, very sensitive, so I can pick up most small leaks. If its smaller than that, I fill it, go home, and run the tube under some water, looking for bubbles. There isn't any leak that can get past the bubble method, but then that one is hard to do on the road.

Most flats I get are from punctures I can see pretty easily after I find the leak. From that point, fixing is straightforward.

Another thing to try is to pump up the tube and hold it close to your ear. You usually can hear the air escaping from the tube at the point of the puncture.

Thanks for the suggestions. I tried the hearing thing but I think all of my walkman listening is starting to have an effect. Miracle Ear anyone?

Sounds like whatever caused the first flat was still lodged in your tire casing. Did you check it when fixing your first flat? I used to just quickly run my finger around the inside of the tire, until the time that I cut a finger when I found the wire that had caused my flat.

Originally posted by roadbuzz
Sounds like whatever caused the first flat was still lodged in your tire casing. Did you check it when fixing your first flat? I used to just quickly run my finger around the inside of the tire, until the time that I cut a finger when I found the wire that had caused my flat.

I can't believe I forgot to mention this step.. Yes, very critical, often if you don't check the tire, you will get another flat. Just try not to cut yourself ;)

Originally posted by Sailguy


I can't believe I forgot to mention this step.. Yes, very critical, often if you don't check the tire, you will get another flat. Just try not to cut yourself ;) Cotton ball.... Use a cotton ball on the inside of the tire run it gently with a little pressure around the inside a tire the thorn, glass, hypo needle, whatever will snag the cotton flagging it. Never can be too careful. (FWIW I live in Tampa so the needle thing isn't too far fetched.)

Yes, in my infinate wisdom I completely forgot to check the tire. It turns out there was a piece of glass (Zima bottle from what the guy at the bike shop said) in the tire. Two pieces. Did not know there was glass on the gound everything was covered with leaves. Went over the front tire last night and there was nothing. Live and learn, I guess.

The first step is to inspect the tread carefully on the outside of the tire. One road tires, often a new punture is noticible. The tube hole will be found below.

Forgeting to check the inside of the tire usually happens only only once. ;)

A little baggy of talc (baby powder) is always nice to carry along to get the tube nice and lubed before reassembly.

FWIW, I usually wind up doing the reverse. The leak in the tube is usually easy to find, so then you hold that against the tire to locate where the puncture occured, so you can visually check the tire, too. (And remove hypodermics, and what not.) Unless it's a snake bite, in which case I don't worry too much about checking the tire.

I had a similar experience, except my experience was spread out over three days. It wasn't a puncture, i was just putting the tire on wrong and riding too hard.

Man...don't you feel stupid walking your bike home?

A lot less stupid than having to push your car home!

Originally posted by Jean Beetham Smith
A lot less stupid than having to push your car home!

:lol: