How long does it take you to change a tire?

It depends on the circumstances. I haven't timed myself but I think I can do a front tire in less than 3 minutes. That would be using a new tube and CO2.

We had a contest a few years ago at a tri club meeting and the winner did it in less than a minute! That was removing the wheel from the bike, replacing the tube, inflating, and putting the wheel back on the bike. I wouldn't have believed it could be done that fast if I hadn't seen it.

I spend one weekend a year practicing..after a few tries I have my kids time me.  I can do it under 2' when things go well.

I think changing my tube about 10x in a weekend is good skill practice. If only I could practice changing my tubulars I'd be happy. Maybe next time I change my tires I'll practice with the old one.  

I never go for speed.  I am really careful about getting the new tube in without having a second flat.  This means finding the hole in the tube and matching it up with the tire to check for embedded glass or thorn.  Then, I make sure the tube is inside the tire without catching it under the bead of the tire.  A partial inflation helps to make sure everything is in place.  Then I pop the tire back on the bead bare-handed.  With a new tire this can really be difficult and take some time.  I figure this takes maybe 10 minutes.  I never time it.

TW

I would never have thought to do this!

I don't remember the last time I had a flat!  I was in to mountain biking before road biking so I learned to change flats very well.  I think I have probably only changed a road bike flat perhaps 3 times.  I have put a lot of miles on my road bike but thankfully haven't flatted too often.  I still have never used my CO2s. 

Probably for good reason. You're taking a chance on ruining a rim, so if $100+++ is "worth it not having to stop," then ride away.

You can do that on tubulars, not clinchers.

If I'm going for speed with a folding bead I don't need tools so about 3-5 for the front and 5 for the rear. Horizontal dropouts make the rear easy, if you know how to hold the chain.

But on a ride I take my time, to make sure I do it right. I've never had to change in a race, though. It would probably take longer from being flustered.

Done.  Not too shabby.