Thursday, March 17, 2011

Blowout

This last Tuesday during my morning bike ride I suffered a front-tire blowout. It happened on a winding downhill portion of the route immediately following a turn. I was second in the group, in front of ten or so other riders following closely in single file.

Pop! Hiss, hiss, hiss, hiss—the unmistakable sound of air escaping a revolving leak. But though a blowout is unmistakable, one has only seconds to react. A blown out 700x23 road tire is flat when its pressure drops much below 80 PSI, and when it's the front tire that's flat, the bike is made nearly incapable of turning, for the wheel rim will slide right off the flattened rubber between it and the road surface and the bike will tip over instead of turn with the wheel. Fortunately, my tire blew out on a straight stretch of road rather than on a turn, and the loud pop of the sidewall blowing out alarmed the other riders enough for me to have room to maneuver to a stop safely on the side of the road.

But what does one do with a blown out sidewall on the side of the road in the dark, pre-sunrise hours? To fix a typical puncture flat, one removes the puncturing debris from the tire and replaces the inner tube. With a hole in the tire itself, any new tube will itself also blow out.

There's a handy fix for this. It's George Washington. A dollar bill makes for an except temporary tire patch for blowouts and, these days, is rather cheap. To use, you fix the flat as you would any other, only before slipping on the tire over the new tube you insert the folded bill between the new tube and tire to cover the blowout. A dollar bill is strong enough to prevent the tube from bursting through the sidewall hole, though every time I've used this technique I marvel at how a thin weave of cotton and linen can reliably hold against 120 PSI. But it has held every time. In fact, one time I forgot to change the tire when I arrived home after suffering a blowout, and I ended up riding on the blown out tire for several months. It wasn't until the same tire punctured in a different spot and my seeing a ratty dollar bill fall out of the tire when changing its tube that I remembered that the tire itself had a hole in it.

Thus, every flat-tire kit should contain, in addition to tire levers, spare tubes, and pump or inflater and CO2 cartridges, a few dollar bills.

2 comments:

Bobby Wein said...

How much would you have paid for the exact same fix at the exact same time if for some reason you knew that the dollar bill would not have worked? Shortening, how much was that dollar actually worth to you? What did you eventually spend it on thereafter? How long did that last? Did whatever you purchased enable to you trade for anything else etc. etc. Fascinating.

cmbrandenburg said...

Bobby— Good questions. How much would I pay not to be stranded in Paradise Valley at 5:45AM? I'm pretty cheap, but I think I would pay $20, maybe $30. Let's call it PRICE_OF_TAXI+$10. The dollar-bill-as-bicycle-tire-patch is one of the few ways in which paper money actually does have intrinsic worth, despite whatever the economic textbooks say about paper money otherwise.