used mountain bike patent
'It's alive!' The one-arm front fork has a garage-engineered anti-dive system (supposedly patented).

Dug Up in the Desert: Buy This Ancient Mountain Bike and You’ll Own Its Patent Too

Anti-dive mountain bikes are rare birds. But if you’ve got cash and a ride to Palm Springs, Calif., you might be able to get your hands on just such a bike — and its accompanying patent.

If you’ve ever done a deep dive into Craigslist, you know how weird it can get. But no matter how many years of your life you’ve devoted to scrolling its mysterious depths, it can almost always still surprise you.

That’s what it did to our internet scavengers when they found a curious listing for a custom-built mountain bike with an anti-dive, single-arm fork. The Frankenbike also has a hand-welded frame, various Sachs components from the ’90s, and hydraulic brakes. It’s located in California, just outside Palm Springs, for $2,500.

Here’s the kicker: According to the (somewhat dissonant) description, the patent for the anti-dive tech comes with the bike. Even weirder, every patent filed in the United States for anti-dive bicycle technology is currently expired.

mountain bike patent

Check out the Craigslist post to read the full description. Highlights include the assessment that the bike and patent present “a serious opportunity for someone to start a business” and a claim that “the German Bike Magazine” called the suspension “the best in the world.” (Efforts to validate that claim or specify the publication it referenced failed.)

sachs derailleur

Calling the thing one-of-a-kind is like calling water wet. It’s easy to identify hand welds and hardware store parts on the integrated anti-dive front fork and hydraulic brake.

Anti-dive systems are more common on motorcycles and cars, but their utility for mountain bikes (especially downhills) is clear. The idea is to keep the bike and rider from pitching forward over the front wheel while using the front brake. The effect helps keep the rear wheel planted, increasing traction and stability.

Several groups filed patents for anti-dive bicycle systems around the early ’90s. But according to our research, each one had expired by 2019. It might be a good idea to approach the patent, and potentially the owner, with healthy skepticism. The description also indicates that the design never made it to production due to “personal reasons.”


On the other hand, why not go for it if you’ve got $2,500 and a vigorous capacity for adventure? It’s not every day you can buy a patent and a literal one-of-a-kind item in one fell swoop.

Sam Anderson

Sam has roamed the American continent to follow adventures, explore natural wonders, and find good stories. After going to college to be a writer, he got distracted (or saved) by rock climbing and spent most of the next decade on the road, supporting himself with trade work. He's had addresses in the Adirondack Mountains, Las Vegas, and somehow Kansas, but his heart belongs in the Texas hill country.