Born from collaboration and innovation, the Buffalo Bicycle Utility’s S2 groundbreaking, award-winning drivetrain builds on years of development. At World Bicycle Relief, we’ve seen firsthand the loads people carry in the communities we serve—from towering stacks of goods to water and family members. Our bikes need to be more than just sturdy – they need to be adaptable.
For years, we’ve worked on building a multi-speed drivetrain that could withstand the harsh environments where we work. In these regions, simple, single-speed systems are typical due to their reliability and repairability. But riders often face difficult terrain and heavy loads—situations where a second gear could make a world of difference.
The challenge for additional gears wasn’t just technical. It was about creating a system that was durable, affordable, and—most importantly—repairable with basic tools.
After plenty of brainstorming, researching and testing, we found a breakthrough solution.
One day, an engineer at SRAM said something that had us rethinking how we were going about everything: There’s a lot of utility in even just one extra gear.
Instead of a complex internal gear hub with three or more gears, we developed a mechanism that uses two independent single-speed chains and sprockets. These work together with a switching mechanism that controls which gear engages the rear wheel. The drivetrain functions just like a single-speed bike but switches between two gears automatically when the rider pedals backward—similar to the way a ballpoint pen clicks between two states.
There seems to be no limit to what people will try and do with a bike because it’s so important. It’s their livelihood, their connection to the world.
In product development, we often say, “We stand on the shoulders of giants,” and the Utility S2 is the perfect example. The knowledge and contributions of engineers, manufacturers, and test riders from across the globe helped bring this drivetrain to fruition.
One of our guiding principles is that innovation must be affordable. By working closely with partners across the cycling industry, we’ve managed to develop this technology at a price point that fits our mission. The S2 drivetrain is not just an upgrade; it’s a game changer for riders who depend on these bikes for their livelihoods.
At its core, the S2 drivetrain isn’t just about technical innovation—it’s about impact. Riders in our communities carry heavy loads, travel long distances, and navigate rough terrain to reach schools, healthcare, and markets. A second gear means accomplishing their tasks more efficiently and with less effort: They can transport more goods, access more opportunities, and improve their overall quality of life.
The S2 is just the beginning. As we continue to push the boundaries of what’s possible in bicycle design, we remain committed to providing affordable, sustainable, and impactful mobility solutions. Thank you for being part of this journey with us.
