It's not cheap to buy good, quality inner tubes these days, so it's not a bad idea
to learn how to repair them yourself if you get a puncture. Now we've already done
a video on how to replace an inner tube, so if you're unsure how to get your wheel
out or how to get the inner tube out of the tire, you might want to head there
first. Now, these days you can get self-adhesive patches which are perfect
for a quick trailside fix, but if you're at home, the safer option is still your
traditional puncture repair kit. A lot of these come with a pair of tire levers in
order to get the tire off in the first place. And all of them will come with
glue, some sandpaper in order to rough up the surface of the inner tube
which aids the adhesion of the patches. And you get various patches in different
sizes. Now, you might wonder why you need different sizes of patches.
The reason that is, of course, if you've got a small thorn going into the tire,
then you just need one single, small patch. But if you've go a snakebite
puncture, which is quite common on a mountain bike, which is where the tire
compresses against the rim, you can often get two holes away from each other.
In that instance, one of the larger patches is more adequate. Right,
so the first thing you're going to have to do is locate where the hole is on the
tube. And for that, you're going to need to inflate it using a pump.
If you've got a very large hole, it's going to be immediately obvious exactly
where the air is escaping from. If it's slightly smaller, then what you can do is
run the inner tube next to your ear and often you can hear where the air is
seeping out. If you can't hear it, if it's a particularly small hole,
then the next step is to take your inner tube to a sink, and that way you'll be
able to see where the bubbles are escaping from. Okay, so make sure that your valve
is done up and gradually submerge the inner tube in the water.
So this one's pretty obvious exactly where it is. See? A lot of air coming out.
So once you've located it, be certain to dry it off, and then you want to mark
where it is so that you don't lose it again. A lot of puncture repair kits will
come with some chalk to do this, but anything that allows you to locate it,
a pen, just so that you don't lose where that hole is. Okay, once you've marked
where the hole is you can let the rest of the air out of the inner tube by
undoing the valve and pressing it in. The next thing we want to do is take our small
piece of sandpaper and just rough up the surface all the way around our small hole.
And as I said, that will help the adhesive of the glue in the patch when we come to
put that on. The next step is to put the actual glue on, itself.
Now, most of the instructions say apply sparingly, and that is an important note
to make. You don't want to put too much on. A little goes a long way.
Once you've applied the glue, you need to wait for it to dry slightly,
which takes around five minutes, perfect for a cup of tea or coffee if you're in
the U. S. The next step is to remove the foil from the back of the patch.
Most patches do look like this. Sometimes they don't have foil on the back,
and, of course, you want the center of the patch to be over the hole as exactly as
you possibly can. Make sure you get it over the center and that there's glue
underneath all of where the patch is. Press it down firmly with your finger,
and it's quite a good idea to take something that's not sharp but fairly
solid and just press it down to make sure that there's no air trapped underneath the
patch. And again, I'm going to leave that just for a couple of minutes to set before
we take this plastic off the top. You need to be careful that you don't take the
patch off with it. So start rolling it backwards. If you do find that it starts
to pick it up, just use your nail to gradually pull it away from the plastic
and make sure it stays on the tire. That's pretty much job done.
You've got some chalk that comes in your puncture repair kit. It's good for two
things. Firstly, you can use the chalk to mark the area where the hole is in the
first place. And secondly, they normally come also with a small grater,
so if you grate some of the chalk up and just put it over the top of the patch,
it will stop the glue surrounding the patch from sticking to the inner tube when
you put it back inside the tire. If you're very confident in your abilities,
then you can just put the inner tube back inside the tire and pump it up.
I'm not, so we're going to put it back into the sink and just check there's no
bubbles emerging from around thepatch. Okay, that looks like it's perfectly
fixed, so we just need to put it back into the tire and pump it up.
And again, if you don't know how to do that, please check out our other video.
By undoing the brakes, and then undoing the quick release. If it's the front
wheel, you need to unwind the quick release slightly so that it clears the
safety tabs at the bottom of the forks.