It was 1976 and dust was flying. A group of locals to Marin County, California had loaded klunker bikes—old cruiser frames with balloon tires, modified with gears and BMX, or sometimes, motocross handlebars—into the back of a truck and driven to the top of a dirt fireroad on Pine Mountain west of Fairfax and Larkspur.

Some of the guys got out of the truck and rode or pushed their klunkers the last two-or-so miles to scout the terrain and warm up. From the top of the fireroad, they set off one-by-one on a wild biking time trial, spaced out two minutes apart by timer and official, Charlie Kelley. That first race, 10 guys tore down the 2.1 miles, descending 1,300 feet fast as they possibly could down the rutty, rocky dirt road.

The bikes would kick up dust and rattle. Their brakes would smoke from friction, so much so that riders would have to go home and re-pack the hubs.

These time trials or bike races became known as the “Repack Races,” and grew in popularity as cyclists wanted to test their mettle on the wild descent and compete against each other for bragging rights.

Small crowds would gather at switchback turns to watch the carnage—occasional spectacular crashes with riders flying over the handlebars or skidding out as they tried to negotiate the turns at high speeds.

For a while, the Repack Races were a weekly event of hooting, hollering, and ripping down what had become known as Repack Road on mountain bikes. Twenty-two cycling races were held between 1976 and 1979, but they stopped happening regularly because many of the riders—including young Gary Fisher, Tom Ritchey, and Joe Breeze—began focusing on their own businesses. They had bikes to build, and created what we know as modern-day mountain bikes.