LP29 Downhill Race Bike
Downhill mountain biking is often regarded as the "Formula 1" of the sport, serving as a testing ground for new technologies where races are won or lost by fractions of a second. In 2016, I set out to design a new downhill race bike that leveraged the mechanical advantages of 29-inch wheels, which had already become a staple in cross-country racing. At the time, no major manufacturer had attempted to integrate these wheels into downhill racing, presenting an opportunity to explore their potential in high-speed, technical terrain.
Project Definition
The primary goal was to develop a competitive downhill bike built around 29-inch wheels. This required multiple design iterations to achieve, analyzing geometry in CAD, modeling suspension kinematics, and evaluating component compatibility. A key challenge was accommodating the larger wheel size while maintaining ride characteristics, ultimately leading to a reduction in rear suspension travel from the standard 200mm to 180mm.
Project Design
To ensure precise alignment of pivot points and maintain frame integrity, I utilized CNC-machining to creates plates as the structural core of the frame. These plates allowed for accurate positioning of critical features while streamlining fabrication. A prototype jig was designed to aid assembly, using a "connect-the-dots method" method to weld the frame together. The design emphasized rapid prototyping and manufacturability to accelerate the development cycle.
Project Delivery
From a napkin-sketch to competition in about two months, I completed the first rideable prototype in time for the April race season opener, making it the only 29-inch downhill bike on the track. By season’s end, I had built four race-ready bikes competing across the Pacific Northwest. The performance benefits of the larger wheels quickly became apparent, prompting other racers to experiment with adapting their cross-country and trail bikes for downhill use. Eventually, the industry took notice, and in 2019, Santa Cruz Bicycles became the first major brand to release a production 29-inch downhill bike, validating the approach I had pioneered.
