New builder row this year was full of engaging new product – there wasn’t a slacker in the house. Out of the batch, Circa Cycles was definitely up there for the most engaging. Rich Fox started the process of Circa four years ago. Having come from the realm of design consultancy, he sought to first examine the problems facing bicycles from a domestic manufacturing standpoint and to build his product from there. Inspired by his first racing bike, an aluminum ALAN Spirit, his medium was set. What he does with it certainly sets it apart from the crowd…
From initial investigation, Rich resolved that there were five obstacles to building bicycles cost effectively and with low ecological impact: heat, paint, tooling, labor, and geometry challenges. With those constraints, Rich developed an aluminum bonded bike that would be simple to assemble, have a durable finish, and would be relatively simple to customize. Why bonded aluminum? Though this method saw its day come and go in the 80’s, Rich argues that bonding is used in modern mission critical componentry in aircraft and rockets as well as in carbon bikes. Because of his process, he’s able to hold the tolerances in the bonding zones much better than was possible the last time this method was used in production.
The biggest visual obstacle to this method is avoiding a pipe-to-pipe aesthetic. To combat this, Rich terminated the five-axis machined lugs at lines that run through the frame. For example, the top tube and down tube termination points on the head lugs are aligned.
Also, Rich took pains to play with finishes both on the lugs and bonded tubes to break up the visual. There were opportunities to add color through the anodized finish such as in the head tube, and Rich took them. Even the chamfer size and placement is deliberate per lug.
There were all kinds of fun techy touches on the bike. The dropout, for example, features a removable hanger in addition to an adjustment screw and indexing lines so you know exactly where your rear axles is.
The seat stays are pinned to allow for belt compatibility across sizes and models. In fact, the whole system has been designed so that parts can be used across different sizes of bikes to help simplify the assembly process. Rich quotes that a whole frame can be fabricated within ten hours using this process.