I carry a std (not HD) 21" and a patch kit. If the rear is patchable I do it, otherwise a 21 works fine to finish the ride or weekend or whatever your tolerance to leaving it in there.

 

I also carry a patch kit. Patching tubes and tires is way easy and reliable if you know what you're doing (it's far from rocket science). There are circumstances where I'd rather patch a tube than swap it out...as I'm about to explain.

One thing to remember is you may not even need to remove the wheel from the bike to patch a tube. For example, with a simple nail/thorn/stick puncture without the valve stem torn off, you can:
lay the bike chain/sprocket side down (there's more space for work on the brake side),
break the bead on just top side of the rim, *
spoon the bead to the outside of the rim if necessary (you might not need to depending on your tire tube combo),
work the tube out of the tire and patch it,
reassemble.

* Even if you remove the wheel from the bike for a full tube swap or repair, you probably only need to break one bead to get the tube out/in. This saves a lot of work and makes it a little less likely to get crud inside of your tire.

 

Good ideas Lutz

 

Awesome i love that idea. How do you know where the leak is on the tube to pull only that section out? Doesn't it get hard to pull it out around the rim lock?

 

Maybe just when you get a nail or thorn and can see where the puncture would be under the tire, It would be had to find a pinch or rub flat under the tire

 

If you can see from the outside of the tire what/where the tire was punctured, it will help you narrow in on the location of the leak, use the location of the valve stem as a reference. You'll probably want to pull the tube all the way out of the tire to make the repair, but you might not need to if you know where the leak is and are very confident in your patching ability. In almost all cases, though, you should be airing up the tube to verify the location of the leak(s)...and make sure to find them all. And then airing up the tube after you patch it to check your work before remounting the tire. If you do air up the tube, it needs to be all the way out so that you don't get a pinch flat between the rim and tire.

Working around the rimlock is no different than any other tire/tube change; it still needs to be loosened before you can break the bead, and even without a rimlock you're probably going to need to spoon that bead off the rim to have enough space to get the tube out/in (flimsy tires and standard tubes are easier, stiff tires and thick tubes are tougher). If you would have enough space to leave the bead inside the rim, except the rimlock is in the way, you should also have enough room to spin the nut off of the beadlock and just get it out of your way - inside the tire or out of the wheel completely - and then put it back when you're ready.

Oh, I forgot to mention before: make sure to look over the outside and inside of the tire, and carefully feel inside the tire, to be sure there's nothing sharp left there to poke another hole in the tube. Seems silly, but people do forget this.

 

What are these "tubes" that everyone is speaking of?