Dear Tom and Ray:

Between yesterday afternoon and this morning, I have had three flat tires. The tire that was flat yesterday had a screw in it, and the tires that are flat this morning have finishing nails. Other than the obvious question of "Was this sabotage?", I have a question about repairing the tires. My question is, are plugs reliable, or are patches or tire replacement recommended? I will add that I am living in Costa Rica, and tire puncturing is a known technique for robbing foreigners. Thus the idea of replacing tires only to have them repunctured is not appealing. But even less appealing is having to stop along a highway (they do not have shoulders) and being held up by the people who put the nails in the tire.

-- Bill

TOM: Well, my first thought was that you need run-flat tires. But I'm not sure that technology is widely available where you live. Run flats require special equipment to mount them, plus they're expensive, require tire-pressure monitors and may not be as repairable as standard tires.

RAY: So, on second thought, you need a 55-gallon drum of pepper spray mounted on the roof.

TOM: Actually, plugs have been used since the days of the Roman chariots. OK, not that long, but they're well-established and effective. As long as the hole in the tire is not too big (and screw or nail holes are not too big), you can insert a plug and expect it to last for the remaining life of the tire -- which in your case sounds like about six hours.

RAY: But even better, a plug is something you can do yourself, Bill. You can go to any auto-parts store (try Manny, Mo and Carlos in Costa Rica), and buy yourself a plug kit.

TOM: It consists of a bunch of plugs, a reamer, which you use to make the hole the exact size of the plug, and a tool for inserting the plugs.

RAY: So you create the hole, then thread the plug into the insertion tool, and then you insert it and remove the tool. And voila! The repair is done and you're on your way.

TOM: So then what you need is a cylinder of compressed air that you can carry around in your trunk. Once you plug your tire, you can reinflate it by the side of the road, hand your wallet to the nice banditos who've been waiting patiently for you to fix the tire, and be on your way. Good luck, Bill.