Bamboo bike frames are assembled in two steps. First, the heat-treated poles are measured, cut and mitered together. Then—since welding isn’t possible—the joints are wrapped with fiber. Calfee uses hemp, or other natural fibers, soaked in epoxy. When the epoxy sets, the joints are virtually indestructible.
“What a bamboo frame has that all other bicycle frame materials lack,” Calfee observes, “is vibration damping. Bamboo wins heads and shoulders above everything else for smoothness and absorbing vibration—both of which contribute to a comfortable ride.”
A ride along the coastal bluffs bears this out. The path is packed dirt, rutted by the recent rains. But the ride never feels stiff or jarring. A hundred yards west, the Pacific Ocean froths with whitecaps. I feel at one with the bamboo frame beneath me: a comfortable blend of state-of-the-art and Flintstones technology.
Along with their artisan appeal, the availability of bamboo makes these bikes an ideal cottage industry for the developing world. Calfee is tapping into this potential. His signature bikes, made in California, run upwards of $3,500. But he also directs a project called Bamboosero, based in Ghana and Uganda.
“During the early 1980s I traveled across Africa and had a bit of experience with the continent. Years later, Columbia University’s Earth Institute approached me to do a bamboo bike project. Ghana kept coming up as a place that had a lot of village bicycle projects, designed to train local mechanics.”
Though Calfee eventually parted ways with the Institute—he prefers smaller operations, while they plan a large-scale bike factory—Bamboosero continues to thrive. The assembled frames, shipped back to California for inspection and hardware, sell for around $700.
Do It Yourself Bike Building
Building with bamboo presents daunting challenges. Unlike steel or carbon, you can’t just order tubes to precise specifications.
“It’s inconsistent in shape, size, thickness and diameter,” notes Lars Jacobsen, a co-founder of Stalk Bicycles in Oakland, California. “And dependability. If you’re building these things, you can’t just jump in headlong. It takes a lot of experience with the material to see what’s going to work and what’s not.”
Jacobsen, 25, is at the point where he uses these quirks to his advantage. When I visit the Stalk workshop, Lars is building a bike for his brother. The frame bars look a bit wavy, but Lars reassures me. “Bamboo grows wobbly,” he reminds me. “And it’s just as strong as when it grows straight. One day, I’ll build the perfect Dr. Seuss bike.”