THE KAYAKER SPIRIT seems right on—if nostalgia were a river, many of them would drown. But with my boat wrecked, I gotta try something else. I decide to storm the dark citadel of the fitness-geek establishment. I will enter a bike race.

A quick scan of the Web shows there's a race in Boulder this weekend (surprise!), and Doug Emerson, owner of University Bicycles, happily loans me a mondo-cool vintage rig. At 5:45 a.m. on a hot Saturday, I ride to the Sunshine Hillclimb wearing a mushroom-cap Bell Biker helmet, thick crocheted gloves, a pink-and-periwinkle wool jersey, and itchy black wool shorts. My bike is a pristine, meticulously lugged white Allegro race frame made in Switzerland in 1973. It has ten tough gears on downtube shifters and a total weight of 25.25 pounds, including the full-length frame pump—not far above that of a modern full-suspension mountain bike. Primo!

I use the two hours before the start to talk shit with some of the 375 competitors, most of whom look like they survive on steroids and baby formula. A few smile at my kit, offering jockish one-liner flattery: "Sick bike, dude." Most simply nod before returning to their stationary trainers and tuning bikes made from repurposed Space Shuttle parts.

Before long we're massed up and preparing to go. My Cat IV beginner's heat bolts off in a cacophony of snaps, everyone clicking in to their pedals as I seek the help of a mechanic to insert my feet into my bike's old-school leather toe straps. Within a mile, I feel groovy and free … of the peloton, which is already a blur in the distance. A waterfall of sweat pours down from my unventilated helmet.

Over the next nine miles I am passed by, among others, a whirring heat of honest-to-God grandfathers and, just before the fifth mile, most of the 15-to-18-year-old twigs. Adding to the humiliation, I realize that weak elastic has allowed my shorts to sag. My pasty white ass has mooned each passerby. I end up in an inspiring sprint finish with a chubby teen I passed while he was resting under a tree. He edges me out at the line. Race organizers and mothers stop disassembling the finish tents to clap for us. One mom kindly offers sunscreen for the red crescent appearing across the top of my butt cheeks.

I finish in one hour and 38 minutes: more than double the winner's time and dead last among all competitors. A few of the best guys arrive at the top a second time, having completed their "cooldown." I lie in the ditchweed panting, waiting for the sweet relief of heatstroke as the previous week's adventures play before me in mildly psychedelic flashbacks.

I have been ignored, nearly drowned, and wholly beaten. As far as I can tell, the spirit of the seventies has shone brightly only in my mind and that of a few insane paddlers. Nobody else seems to care. I begin to feel sorry for myself—until I realize that there is one last place I can go, one final arena that promises solace.

And I think you know what I'm talkin' about: Boogie Night!