Swiss-based independent bicycle brand Open has unveiled its latest and most expensive road bike, the Open MIN.D. California.

The bike was designed by Open co-founder Gerard Vroomen with composite design specialist Don Guichard, both of whom worked on Cervélo's infamous Project California over a decade ago. Rather than adding a practical, mass-market model to Cervélo's R series, Project California was intended to test the limits of bike design, and was the driving force behind the R5Ca and RCa, two of the lightest and most expensive top-of-the-line frames in Cervélo history.

Open launched its first road-specific bike, the MIN.D., in 2020 to critical acclaim. The brand first gained notoriety in 2015 with the release of the U.P. gravel bike, which had the silhouette of a road bike but offered clearance for ultra-wide 2.1" tires and was widely considered one of the best gravel bikes on the market when it was released . Given its gravel bike lineage, many were surprised to see a dedicated road bike from Open.

With MIN.D., Open fans found a more modest, more conservative road bike that maintained the DNA of its quirky, genre-busting first release. That DNA can be seen in the MIN.D.'s unorthodox geometry (perhaps best demonstrated by the unusually long 50mm fork offset) and comfortable 32mm clearance. While most brands have recently moved away from integrated seatposts, Open's MIN.D. uses a "continuous seat tube" with a narrow diameter of just 25mm. In theory, this improves the vertical flex to the saddle and rider. [The MIN.D. California retains the signature elements of the MIN.D. while evoking the same aesthetic and engineering story as Cervelo's Project California. This is sure to excite those who are tired of frames manufactured in the Far East, and echoes the efforts of other brands to bring production closer to home, such as the €15,000 BMC Masterpiece.

Gerard Vroomen, who founded Open and is now CEO of 3T, also counts founding Cervélo among his bike design credentials. It was around that time that he hired Guichard to develop Cervélo's Project California frame, which had a total weight of 600-700 grams.

Since then, Guichard and Vroomen have stayed in touch. Don ran the R&D lab/factory at Project California and created the crazy light and stiff Cervelo R5CA and RCA. After the frame project shut down, he continued to build other parts, including carbon fiber prosthetics, but he really wanted to build frames again."

The two began work in the exact same carbon lab in California as before. Under normal circumstances, one would expect the finished tubes to be wound together with carbon prepreg sheets. ......

Treating the project as a skunkworks-style test of the limits of technology, Vroomen claims not only to have lightened the already skinny MIN.D. (down 80g in the end), but also to have stiffened the bottom bracket area and improved vertical compliance.

Perhaps hidden by the simple finish, the MIN.D. California's tube geometry is quite different from the standard bike, with new layups and carbon fiber materials.

Perhaps the scales tell the story best. According to Open, the MIN.D. frameset weighs 775g for the L size. While not quite as light as the Specialized S-Works Aethos at 588g, the MIN.D. California still outperforms many lightweight bikes on the market.

At €7,500 for the frame alone, and in limited production, the MIN.D. California admittedly offers less return for both the rider and the brand itself when compared to Open's regular MIN.D. frames. In that sense, Open admits that the project has gone hopelessly off the rails.

"The advantage (or disadvantage, one could say) of the Open structure is that Andy [Kessler, Open's co-founder] and I don't have to justify our investment or expenses to anyone," says Vroomen.

"That's why we just kept going with this California MIN.D. until it was finished, even though it made no commercial sense along the way."

Given the limited supply and boutique nature of open MIN.D. California, we may have a hard time getting a sample of California MIN.D. and making our own judgment. In any case, MIN.D California will easily fit into our ever-growing list of dream bikes.

The Open MIN.D. California is already listed on the Open website and will be available in the UK through partners such as CycleFit.

Sizes: small, medium, large, extra-large

Price: €7,500 (frameset only)