This really ruined my commute this morning on my way to work. And it was a duo path job too. Top and bottom tube repair. Right there next to the road. Cars whizzing by at 50 mph!
Then I went to the office at break and "What the W-T-F is this? It's flat!!"
So at lunch I break it down. Is it the top patch ort the bottom patch that failed me? Maybe both the way my days going.
So I pump the tube up and take it upstairs, across the hall, down another set of stairs to the utility closet. And what did I find?
NOTHING!!
Not a bubble anywhere. I must of failed to tighten the damn stem's valve all the way. It's happened before.
But on the bright side both my patches held while done in hast. And I was only 12 minutes late for work.
And I still got to ride my bike to work! Love riding to work.

Could be a "ghost" puncture: usually happens when its patched 99% correctly, a wee little bit of air leaks out so the tube can stay relatively hard for a few hours before you need to inflate again. They are a real pain in the ass because you never realize it until its too late. You suddenly flat out and when you check you can't find a physical puncture, and when you inflate the tube its almost impossible to hear such a small amount of air whizzing out. The solution is to simply patch it properly, except when you have multiple patches and have no idea which one was the most recent one....

It could have been worse. I had a nail go through my tire inner tube and put a deep gouge in the rim. I had to slide a dollar bill in between the tube and the rim to make sure the rough edge of the gouge didn't cause another flat. When I go home I deburred the gouge and filled it in with epoxy.

you the man!

When that happened to me once the nail bent when it hit the rim so that the nail then ripped out the sidewall of the tire.

Done that .. Debris happens.. pulled out the nail put my spare tube in and finished my Trip. Gatorskin Conti MTB size travel contact.

Nope. Its flat this morning. I'm a failure!

Use the pot of water method to find the leak.
Cheers,
David in Alaska

I usually take the tube out and overfill to find the leak. Pass the tube close to your lips to try and detect airflow. Your lips are very sensitive, and I rarely need to resort to soap and water to find a leak.

The other advice I have for patching is to make sure that you wait long enough for the glue to dry before applying the patch. Wait at least 5 minutes - longer if you can.

Replace the tube. Sometimes it's not worth getting aggravated at an inexpensive, inanimate object. FWIW, that's why I carry at least two tubes on all my bikes. Fixing roadside flats isn't usually enjoyable under the best of circumstances; trying to find a small hole on the side of the road with 50 mph traffic around me, then abrading the area, waiting for the glue to dry, etc. No thanks. I'd rather replace the tube, get back on my way, then at home I can patch a bunch of tubes at one time - usually on a cold, or windy Saturday afternoon.

Ha! That's just whati did today at lunch! Went to the LBS and just picked up a new tube. Luckily I had a spare car to use.

Oh yeah, I meant to say that too. Much easier to apply a quality patch in a well lit, air conditioned space than on the side of the road with dirty hands, poor light, and speeding cars.

So one of the patches had a very slow leak. Too slow to produce a trail of bubbles. I wiped one bubble away from the edge and another one appeared in its place. And it would just sit there untill I wiped it away so it's another could take its place. Replaced the path and took my sweet time doing it and now there's no bubble appearing. And I have a spare in the bag for next time.

Yikes! Not fun (other than the riding...always fun!) I had a large nail ruin my commute home last year.

Not fun, I hit a similar ~2 inch nail last summer with a new Schwalbe Marathon Plus tire. Patching the tube was not a big deal. Anyone have suggestions on patching the tire itself? If I inflate the tube it starts bubbling up through the hole in the tire. It is a shame to have that *new* tire just sitting there in the basement.

I ran over a 1 1/2" wood screw last week. Glad I carry a tire boot because it put a serious hole in the tire.

I've patched a tire too, - just put a patch on the inside. Can't say how durable it will be over time. The tire I did that to was nearing the end of its life and I replaced it not long after.

Tire boot! Ordering a pack tonight!

I had a flat once in which I could not find the leak because it was a time when I still didn't know how to pump up a presta valve. So I put everything back together and rode the bike riding on the rims all the way to the nearest subway station. Then I took the subway to the Bike Pirates, the local volunteer DIY bike shop.

You can use old tires too. Just cut up a few inches. Make sure to cut off the bead, of course.

I have heard of doing that too, but I never knew what kind of adhesive to use. Any suggestions?

I don't use adhesive, the pressure of the inner tube keeps it in place.

If the hole isn't too gaping, you can use a piece of duct tape as a boot. The piece should span both beads, to resist creep:

Did you break down your wheel just for this shot?

Haha, nope. I was able to get an additional 150 miles out of this tire, then gave it an honorable discharge after snapping this picture.