TUCSON, ARIZONA. After getting a flat tire a few miles west of Kent, Texas it occurred to me that riding a motorcycle isn't very practical. There is no trunk. There is no spare. The only way to get in motion again is to find the hole, plug it, and reflate enough to get to a gas station. After that, it's time to buy a new tire.

I got my new tire installed in Deming, New Mexico and then headed for Douglas and Bisbee Arizona, the long but 'Old West' way to Tucson. Unfortunately, I then encountered another of the joys of motorcycling--- exquisite sensitivity to weather.

A cold front was blowing through. By the time I got to Douglas the temperature was in the 40s and I was looking for new layers of clothing. Heated grips helped. So did having an electrically operated windshield that could be raised.

But I was still cold and had another two hours of riding. I fixed the problem by putting on a windbreaker over my leather jacket--- and just in time because there was some light but very cold rain, too.

As I said, traveling by motorcycle isn't very practical.

The next morning I decided to visit a Mecca for bikers--- Iron Horse Motorcycles in Tucson. I would buy an electrically heated vest. On the way I had a near accident and dropped the bike just as I came to a stop. In addition to being shaken by how close I had come to a major accident, I now had to pick up the 600-pound bike.

But I didn't. Two drivers, in separate cars, ran to the bike, brushed me aside, and lifted the bike. Then they told me to get on. I felt like Blanche Dubois in Streetcar Named Desire.

"I have always depended", I wanted to say, "on the kindness of strangers."

On the bike again I noticed that the right foot peg had broken off when I dropped the bike. Now I had another reason to visit Iron Horse--- a replacement peg. By the time I arrived at the shop, I was having second thoughts about my coordination, my judgment, my sanity, my maturity, and my innermost desire to live a long life.

Enter Martin Cohen.

The owner of Iron Horse, Mr. Cohen is a near life-long rider. He started when he was 12. After that, he only wanted to ride. In college he got a degree in mechanical engineering, a ploy that made his parents happier than his desire to be a motorcycle mechanic. The engineering degree, however, turned out to be good training for running a top-notch dealership and his business has thrived on those who love BMW motorcycles.

You need to understand that motorcycle riders are members of different tribes. They will stand together against automobiles, but they have basic doubts about those who ride other brands.

One example: the best selling T-shirt at Iron Horse has two statements:

•           This is your brain. (A BMW emblem is depicted.)

•           This is your brain on drugs. (A Harley Davidson emblem is depicted.)

BMW riders wear helmets. They also tend to be distance riders and loners. Harley riders don't wear helmets, having a deep belief that their brains will regenerate themselves. They also tend to be town riders and to travel in packs. Neither tribe understands the adrenaline freaks that ride the "crotch rockets" from Japan.

I asked Mr. Cohen who his customers were.

"It's the people I went to college with. In their 20s and 30's there were no motorcycles. But in their 40's and 50's they come back. These come-back riders account for about 40 percent of our sales."

Men like me, in other words.

Mr. Cohen explained that the average age of motorcycle riders had been rising for years and was now 38, with lots of riders returning or starting after their 40's.

But don't take his word for it. Or mine. Francis Glamser, a professor of Sociology at the University of Mississippi, has done a study of 100 older bikers and found that they weren't crazy people with suicidal impulses. (I should mention that he is now in his 50's and is a rider himself, a fact that may influence his interpretation.)

Reading his study, I felt it was all about me. If you are one of the many readers who felt a pang of envy as I reported this ride, allow me to make a suggestion--- read Professor Glamsers' study and see if its about you.

If it is, you may need to buy a motorcycle. If you do, just remember one thing.

Keep the shiny side up.