Flat Tire Rules

Bicycles, for the most part, use pneumatic (that's technobabble for 'air-filled') tires. There are a few exceptions, but quite frankly most of them don't work anywhere near as well as pneumatic tires for the intended purpose: they're heavier, usually slower, rougher-riding, and don't protect your bike's rims as well.

Thus, cyclists, for the most part, accept the occasional flat tire as the small price we pay for a faster, smoother, lighter, sproingier ride than might be provided by, say, iron-shod wood or closed-cell foam (besides, we'd all look silly carrying around iron-shod wood spares).

However, it's worth noting that there are certain physical laws of the universe involved — or, shall I say, clauses within the greater set of Murphy's Physical Laws — that determine exactly when, where, and under what conditions a flat will occur.

For the edification of my fellow Not-Very-Well-Informed Cyclists, I present them here:

Murphy's Laws of Pneumatic Bicycle Tire Tube Mechanics

1. Most flats will occur on long rides, usually at the furthest point from home or civilization.
2. The presence of a cell-phone 'Dead Zone' greatly increases the likelihood of a flat.
3. The omission of a patch kit, wrench, tire levers, or other requisite tire-changing tools greatly increases the likelihood of a flat.
4. If you are in a cell-phone 'Dead Zone' without your tool kit, a flat is nearly inevitable.
5. When riding in a cell-phone 'Dead Zone' with no means of changing or repairing a tire while wearing cycling shoes that make walking nearly impossible, you should really just give up and wait for the next better-prepared cyclist, passing car, or search helicopter. It will be easier in the long run. However, the Universal Law still dictates that your tire will, with certainty, go flat at some point while you are waiting.
6. Flat tires will almost always occur on your rear wheel. Engineers will attempt to reassure you by saying this is due to weight distrubution. Don't be taken in. The sole reason that the preponderance of bike flats are on the rear wheel is that the rear wheel is harder to remove than the front one. This is doubly true if your front wheel has a quick-release hub and your rear wheel doesn't.
7. If you do not have a quick-release hubs, your tire will go flat on the one day out of the year that you have forgotten the requisite wrench for removing the wheel.
8. If you do have quick-release hubs, your tire will go flat on the one day out of the year that you have not remembered to bring tire levers.
9. If you have quick-release hubs and tire levers, the rear tire will go flat on the one day you have brought a patch kit but not a spare tube, and the damaged tube will prove to be beyond repair.
10. If you have quick-release hubs, tire levers, and a spare tube, but no patch kit, the spare tube will turn out to be defective or the wrong size. Meanwhile, the highly-reparable damaged tube will silently mock you.
11. If none of the above conditions apply, your wheel will go flat on the one day you've forgotten your frame pump.
12. If by the grace of God none of the above conditions apply, you will find that your frame pump:
    
    • is defective.
    • is mysteriously incompatible with the valve type on the tube you need to fill.
    and/or
    • has somehow disappeared during the ride.
13. If a miracle has occurred and absolutely none of the above conditions apply, your tire itself will have mysteriously disintegrated, and really — how many of us carry a spare tire on every ride?
14. If, somehow, you have managed to avoid all of these pitfalls, be prepared to change your tire and ride like the wind, because zombies, ninjas, the armies of the Apocolypse, or possibly all three will be close behind you.

One last law:

• The moment you think, "Gee, I haven't had a flat in a long time!" the Powers That Be will smite you.

I am absolutely certain that there is some celestial being or another whose mission is tracking down cyclists who are thinking exactly this thought and popping their tubes. I believe the being in question may be the same one who subjects drivers who say, "We're making great time!" to immediate sidewall blowouts.

The best way to manage all these potential disasters, of course, is to pack plenty of snacks and water, Gatorade, or the beverage of your choice, and possibly also some Valium or vodka, on any ride longer than three or four miles (make that 'three or four blocks,' if you're in those cycling shoes that make walking nearly impossible; 'three or four meters' if you're in those cycling shoes that make walking nearly impossible and have developed blisters). That way, you'll at least be well fed and hydrated while you wait for help.

Addendum: Come to think of it, a PSP, iPhone, or other video game system and an extra battery might also come in handy. Or, if you prefer, an iPad with plenty of pre-loaded e-books.