Save your seat.

Q I'm tiding a bike through New Zealand this winter and was wondering if you had any suggestions for preventing (or at least coping with) the inevitable pains that are sure to afflict my, um, rear end? SHAUNA LIVINGSTON, Toronto

A The most important three things to remember before embarking on a multiday bike tour, according to Chris Cole, director of the annual AIDS/LifeCycle bike ride from San Francisco to Los Angeles, are a comfortable seat, a properly fitting bicycle, and time in the saddle. "The more she rides and trains, the better she's going to feel all around," Cole says. While your first instinct may be to get the widest, most cushy seat available, remember that the more direct contact your body has with the surface of the seat, the more likely it is to cause chafing. Many bicyclists prefer leather seats to plastic because they conform to the contours of your body over time. No matter how unstylish they may seem, Lycra cycling shorts' lightly padded liner could literally save your arse. And to help reduce the friction between your perineum and the seat, Cole recommends keeping your sensitive spots lubricated with Butt Balm or Chamois Butter. "It's less viscous and more comfortable than Vaseline." When you're out there cruising up and down the rolling hills of Kiwi country, pedal standing up as much as possible (this is called "honking," a term originated in England and also used in New Zealand).

Q When I travel i'm paranoid that the X-ray machine at the security check will damage my film, so I end up packing my digital camera instead. Can X-ray machines really harm unexposed film? PEGGY SHARP, Reno

A The higher-powered post-9/11 security scanners used for carry-on baggage generally have no effect on undeveloped film under ASA/ISO 800--unless it passes through more than five times. To be safe put your film in a clear plastic bag without the canisters and request a hand inspection, especially if you plan on passing through multiple X-ray machines. The Transportation Security Administration advises not to place undeveloped film in your checked baggage, which is subjected to more powerful radiation. Of course, if you simply process your film before flying home, your only worry will be finding last-minute airport souvenirs for your gal pals.

Q I heard that in Thailand it's considered improper to touch someone on the top of the head. Are there any other social customs I should be aware of when traveling in this country? JUSTIN UNDERWOOD, Santa Cruz, Calif.

A Thailand may have one of the most easygoing, gay-friendly populations in Asia, but that's no excuse to disregard the country's long-held social mores. While the head is indeed considered the most sacred part of the human body, the feet are considered the lowliest. Thus it is impolite to point your feet at anyone or toward the altar in a temple or to put your feet up on furniture. Avoid stepping on doorsills when entering someone's residence. Thais believe that stepping on the doorsill will offend the deity who resides there. Staring is also considered impolite--even intimidating. The smile, however, is one of the most common Thai expressions, as it is in many parts of Asia, and can be used for almost any occasion: to greet, thank, apologize, or even cover up an embarrassment. Smiling could come in handy if you accidentally, say, touch someone on the top of the head.

For Web links to more information on bike seats, traveling with film, and foreign customs log on to www.outtraveler.com.

HAVE A TRAVEL QUERY? E-mail [e-mail] or write to The Out Traveler, 6922 Hollywood Blvd., Suite 1000, Los Angeles, CA 90028