Monday, August 8, 2011

A bad, bad inner tube gets what's coming to it

fixed, a bit later in the day
Tried to take 2 kids out with me on the old Schwinn tandem and pulled it out of the garage only to find that the front wheel, which had been fine the day before, was utterly flat. Great!, I thought. A maintenance task for the LGRAB games! Out came the old metal tire irons and patch stuff. Off came the front wheel.
Tire coming off

Rrrgh. The hole wasn't in the tube itself. It was in the rubber surrounding the valve stem. Rubbing on the steel of the rim for years had done it in. Even with a patch over it nothing would hold it closed. Any patch just blew off with no tire behind it holding it in place. Tried it a couple of times, even.

Eventually gave up and put in a new tube. The old one, it turned out, had been the wrong size and was folded over itself inside. A neat trick if you don't have access to one that really fits, but not ideal.

Finally got it redone, headed off and had a nice afternoon, with the big kid actually pedaling along!

     To do this yourself, get your patching tools together, with a tire patch kit, tire irons (plastic ones are nicest to your fancy aluminum rims), a wrench or other tool to take the bike apart and put it together (often 15mm on newer bikes), a new tube to fit your wheel that has the type of valve you use (Presta is skinny and Schrader is like the ones on a car) and a pump or compressor. A new tube is fast but if you can fix the old one it will be just fine and it's a lot cheaper. The whole process takes only a few minutes. Need a new tire? Now's a good time to change it. If your bike is Dutch, internal geared, or otherwise very difficult to take apart, and you can fix the old tube well, you can do the rest of this stuff without removing the wheel and without a new tube.
     Notice where the washers and nuts all go on your wheel compared to the fork ends, and unhook any safety thingies. This bike has screw on wheels, but if you have quick release levers you'll probably notice they're not that quick, really, since you probably have to undo the lever, then unscrew one side or the other, for the nuts to fit over the "lawyer lips" you likely have on your fork, or unhook any little tabs from the slots in the fork. The brakes should fit over the flat tire as you pull it out, or you can loosen them if needed. If you have a classic Raleigh you have a special case, and you need to put the wheel back exactly right. Mark the right side and the left side of the wheel, or, better, read this first. Some tires have to go in a certain direction - check yours.
     Take the wheel off the bike, then use the tire irons to gently lever one side's tire bead (inside the metal of the rim) up and over the rim toward the outside. Continue along, levering more and more off until the entire side of the tire is off the rim, leaving the other half still attached, and pull out the flabby flat inner tube. At this point you can fix the tube, usually, following the instructions that come with your patch kit. Pump it up, find the hole, use the kit.
     Check for bad things inside the tire or rim. If you find a piece of something sharp or a rough spoke end sticking through the rim tape or rubber rim band, you can remove it now or smooth it and cover it with new rim tape or a tire patch or thick duct tape. If there is a hole in the tire itself, it has to be pretty big to cause any problem. If you need to you can use a tube patch on the tire, or a stiff piece of paper like a new dollar bill can cover a big weak place until you get a new tire.
     Insert the new tube, slightly inflated, into the tire. You put the stem through the hole first, which should traditionally be near the brand marking on the tire, then stuff the rest of the tube into the tire. Even it out without too much twisting or pinching.
     Write in your contact information and put it in on a piece of Tyvek from a FedEx pack or similar including your name, telephone number and instructions to call you if the bike is taken for service (theft protection), write it on the rim tape, or Sharpie marker it onto the inside of the rim or tire. Rough notes can eat into the tube so make yours small and smooooooth.
     Reinstall the tire. Start near the stem and go around both ways to click it in. Often with mountain bike tires you can do this by hand, but these old Schwinn Westwinds needed a little oomph from a tire iron. Be careful not to pinch the tube (jab it in before levering the tire bead) or you'll be popping holes in tubes and doing this again and again.
     Put the wheel back with the tire mostly flat so it fits in between the brakes (assuming you didn't unclick the quick release on them - the old Schwinn doesn't have any kind of quick release). Attach the various lawyer safety things and washers just the way they were and screw everything in properly (or use the quick release. Put it in the loose way then move the lever to tighten. Too tight? Loosen the screw a bit and try again. Make the lever point back so hooking it on a bush won't drop out your wheel.)
     A back wheel is similar but more complicated to remove and replace. Make sure a back wheel is even so it doesn't drag on things before you tighten it down.

Did you enter the LGRAB games?


  1. Ooooh, hiding your contact information in there is a good idea! I hadn't heard that before. At our local bike kitchen, they advised during a workshop that if you're doing this at home, right after checking for bad things, add a little baby powder inside the tire and roll the tire all the way around to distribute it before you re-insert the tube. By lubricating the tube this way, you keep the tube from getting a pinch flat while you install it.

  2. That is a good idea about the contact info. And my quick releases are, in fact, very quick. I recently switched to this new kind of bicycle quick release, that doesn't require any adjusting. You just have to open and close the lever to get the wheel off. It was such a small change, but one of the better upgrades I have ever made to my bike.


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