Waterland Farm

Land between the Hazel and Hughes Rivers

in Rappahannock County Virginia.

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Tube Patch

You may find yourself in a situation that you have a flat tire in an isolated location. AAA will not come out there to help you, there is no service for your cell phone and your car is several hours walking away. So it is up to you.

You can handle the situation in three ways: 

1. You can start walking;
2. You can put on a new tube; or
3. You can patch the tube, which is by far the easiest approach.

This page is about patching a leak in a tube. When it mentions the word tire it means the part that meets the road; when it speaks of a tube, it means the part inside the tire that holds the air. The wheel is the metal part around which the tube and tire are fitted. The rim is elevated outside part of the wheel; each wheel has two rims.

This page assumes that you have the basic materials for patching the tube. So, before you go on your trip prepare your tube repair kit. You don't need much and what you need is inexpensive.

1. First you need a tube of rubber solution. In the old days, people made it themselves by dissolving rubber in gasoline. But since pure rubber is now difficult to find, it is better to get some solution for a few cents at a bicycle shop or a Wal*Mart type shop. Wrap it air tight in plastic film, because the content is very volatile and it may have become hard and unusable if you need it after some time.

2. You also need two flat pieces of metal (tire lifters) to pry the tire of the rim. They sell inexpensive special tools for them. You can also use medium-sized screw drivers.

3. You need something to patch the tube with. They sell pre-cut patches and these are very convenient. You can also cut some pieces in various sizes (to match the size of the puncture) from an old tube.

4. You also need some material to clean the site on the tube to be patched. Gasoline is by far the easiest to use, but it is not suitable to carry along. So use a bit of gasoline to clean a tube for repair at home, but put a small piece of fine sand paper in your kit for field repairs.

5. Finally you need a small pump to inflate your tire during and after repair. A bicycle tire should normally be inflated to some 60 lbs/sqi but your small pump may bring you home on perhaps 20-30 lbs/sqi.

All this sounds sounds like a lot, but (except for the pump, which should be attached to you frame) it is only a handful that is easy to put somewhere.

Now here you are with your punctured tire and your tube repair kit on a lonely road. What to do? Here we go:

Put your bicycle upside down, so that it rests on its saddle and handle bar.

Locate the approximate area of the leak. Perhaps you see a nail or piece of glass stick out. If  it is a significant puncture you will hear the air escaping from the leak. If you cannot hear that, it must be a small leak. Perhaps you don't need to repair it right here and there and you can get by by inflating the tire a couple of times on return to your car. Also, make sure that it is not the valve that leaks (possibly because of dirt); if so a few strokes with your pump may help. If nevertheless the tire loses air too quickly continue as follows.

At about a foot to the left of the leak, place one tire lifter between the tire and the rim (making sure that the tube is not between them) and pry the tire on one side over the rim. Hold the screw driver with the tire over the rim with your left hand and with your right hand place the other tire lifter between the tire and the rim about 1-2 inches to the right and again pry the tire on one side over the rim. Now remove the first inserted tire lifter (making sure the tire stays over the rim). Continue to pry the tire over the rim so until you are about one foot to the right of the leak. The prying will be increasingly easier and the whole process will not take much time. If you have no idea where the leak is, you will have to pry off the whole tire, but only on one side of the wheel. If the leak is on your rear wheel, select the side where there are no gears to work on.

Now, pull out the tube and locate the exact spot of the leak. You may have to inflate the tube a bit to do this. Mark it with a ball point or scratch it with something sharp if it is not clearly visible.

Clean the leak site with sand paper over an area somewhat larger than the patch you need to put on. Select a patch of appropriate size and also clean the patch if it is a patch made from an old tube. Wipe off sand paper residues.

Put on a thin layer of rubber solution around the leak and also on the patch if it is an old tube patch (a commercial patch has the solution already on it). Spread it with your pinkie and wipe your pinkie clean on your trousers. Thin is the operative word here. Don't put on too much. Now (and this is critical), if you put the patch on the leak right away, you are in for trouble. Wait, wait perhaps one minute or even more until the rubber solution has dried somewhat. Then stick it on. If the patch curls up, you put it on too soon. It is easy to put it on too soon, but difficult to put it on too late.

Put your fingers inside the tire to feel whether there is anything sharp protruding from the inside at and around the leak area. If so, remove it. If not, put the tube back inside the tire. If you took the valve out of the hole you may have to do some wriggling to get it back in. Then put a little bit of air into the tube so that it just rounds out. This is important to avoid that the tube gets caught between the tire and the rim of the wheel. Make sure that the valve sticks straight out of the wheel. If not, grab the tire and move it slightly to get the valve in the right position.

Now you have to get the tire back over the rim onto the wheel. Do not use the screw driver, at least not right away. Go to the side of the wheel where the tire is not over the rim. The motion to perform is hard to describe, but (starting at the point where you began taking the tire off) put both hands firmly around the tire and pull it in a circular motion towards you to get the tire over the rim. This may require some force. Generally you will get in this manner the tire back in place. Should you need to use your tire lifter to get more leverage, be very, very careful not to get your tube between the tire lifter and the rim.

Finally, inflate your tube. Your tube is now as strong as before. Even if you wanted, you could not get the patch off the tube again.

If you brought a new tube with your repair kit,  you would save the patching part, but the other work would remain the same. If the flat was on your front wheel, it would be easy to put on a new tube because the wheel is easy to detach. If the leak were on the rear wheel it would not be quite as ease with the gears and all that.