My first mountain biking race was in 1987 at that granite monolith in the eastern Sierra, Mammoth Mountain. I wore a goofy yellow helmet that had, I think, exactly zero air vents, and my bike was unsuspended, front and back. Come to think of it, I don't think anyone had any suspension at the time, even at the NORBA World Championship. That's right: World Championship. They could call it the World Championship because we Americans owned the sport. We invented it on Mt. Tam and the Euros were, for another year or two at least, still skinny-tire weenies. The great veteran runner/rider/triathlete Ned Overend (aka, The Lung) won the race, and I can't remember what happened to John Tomac, the emerging sport's young endorsement-besotted turk. I finished far back but strong, strong I tell you, on my Univega Sport, which weighed in at probably 40 pounds, including the rack on the back.

The point of this windy recollection is as you expect: To establish my street cred as a mountain biker. Because 15 years and a lot of miles and a lot of races later, I've turned on my tribe. Or maybe not. This is my problem: I love mountain biking, but I very much dislike mountain bikers.

I didn't fully realize all this until a visit last Sunday to Skyline Park, on the southeastern edge of our fair town. We were there for a walk in the Native Plants Garden, but the park proper is the only legit mountain-biking option that a Napa resident can hit without loading the bike into the car. As we pulled into the parking lot--me, my wife and almost-3-year-old son--we noticed a pack of mountain bikers getting ready to roll. They had dual suspension, Camelbacks, the latest frame technology--all the accoutrements of fanaticism, or at least weekend warriorism. I was immediately irked that they had, in fact, loaded their bikes into the car and driven to Skyline. Skyline is nice riding, but there's as good or better to be found all over the Bay Area; it makes no sense to come to Skyline from afar. And if you're local, why not ride to the park?

Then they took off and I could tell by the belly-driven tone of their conversations, by the way they shot down the little grade that connects to the trails, by everything about them, that they were ready for some hardcore riding. Never mind that it was Sunday and the park was full of hikers. Never mind that Skyline's track is often narrow and a hiker wouldn't have a prayer getting out of the way of a bike coming around the curve on an off-camber, gently down-sloping stretch. Never mind, moreover, that any other visitor's goal of some modest communion with nature--its sound, its quiet, its delicious lack of human intrusion--would be exploded by the presence of these cyclists.

The question I had wasn't how hikers could have a good time under these circumstances--it was how cyclists could.

A few days later, still thinking about all this, I gave my road bike a rest and pedaled my '96 Bontrager Privateer S (Indy shocks up front) over to Skyline. It was 5 p.m. on a weekday and nobody was there. I clambered up the Lake Marie fire road, cleaned a wicked rocky, rutted, singletrack climb and swooshed down the hill in the invigorating cool ocean breezes rushing from the Bay to the south. Good golly, I had a good time.

Alone.

I didn't bother anyone. And nobody bothered me. I knew before I even hit the dirt that it was unlikely I'd come across even a single hiker. And I didn't. This freed me to ride unencumbered, and that made all the difference.

There isn't a chance in the world I would have enjoyed myself if every half-mile or so I had been coming across a hiker. I would have known I was wrecking their experience, and fears of a collision would have distracted me. (And a distracted mountain biker is a bleeding mountain biker.)

Where does that leave me? Here: I now know what it is, exactly, that I dislike about mountain bikers. It's their unwillingness or inability to empathize with other trail users. No matter how courteous they might be, mountain bikers on busy, narrow trails are a pain in the ass. Period. They take more than their share of the space, in every sense. They are selfish. But go ahead and ride. Ride hard! Just do it when you won't be bothering everyone else. You'll like it even more.