The North American Handmade Bicycle Show (NAHBS) has become one our sport’s eagerly awaited functional art exhibits each season. Every year, small builders find more creative and artistic ways to build bikes, and no matter what exotic materials and construction methods ensue, the end products are all fully rideable.
Earlier this week on singletrack.com, we got a sneak preview of a voluptuous, belt-driven Black Sheep titanium singlespeed headed East to Richmond, Virginia for display on the show this weekend.
Now, to whet your appetite for our upcoming coverage of more sweet bikes, we stole an advance look at some hybrid bamboo-carbon bikes built by Boo Bicycles. Just after finishing the final assembly of his show bikes, owner Nick Frey stopped by VeloNews to show off his creations before packing and shipping them for display. One of them was a custom, belt-driven cyclocross bike, and the other was a singlespeed 29er mountain bike.
In addition to getting Boo Bicycles off the ground, Frey races full time for the Jamis-Sutter Home road team. While he races Jamis bikes, on off days he is allowed to ride his own Boo, and he’s even won a race on a Boo frame. We chatted while VeloNews photographer Brad Kaminski snapped away.
Powered by Princeton
Just a few years ago, Frey was a mechanical engineering student at Princeton University. As part of a team project in his junior year materials design class, he and three friends decided to build a bamboo bike in which bamboo tubes were joined to each other with carbon fiber wrapped joints. “We thought it would be an awesome way to showcase this new material,” said Frey, adding that Craig Calfee’s pioneering work in bamboo bikes was an inspiration.
“We started out just wanting to see if we could do it,” said Frey, noting that the first bike didn’t look nearly as polished as the bikes now made by Boo. But he managed to race it in a collegiate event at Rutgers, and after presenting the bike project in front of the class, Frey’s professor suggested creating a business and actually selling bike frames at retail.
The original project and business plan didn’t work out, but after some early publicity, James Wolf contacted Frey. Wolf is an ex-pat American who has been building bamboo furniture in Vietnam for the last fifteen years. “I knew we couldn’t build the bikes ourselves, especially being in school, but I also knew it just was not doable for how much labor they take, to have a skilled labor person do them in the U.S.,” said Frey. So he started talking to Wolf about how to make the business viable, and Wolf began prototyping a series of frames.
Getting the frames dialed in for stiffness and handling took almost a full year, but Frey and Wolf launched Boo Bicycles at Interbike 2009, and haven’t looked back.
The making of a high-performance bamboo bike
Getting a bamboo bike to ride as well as higher-tech carbon fiber and aluminum bikes isn’t easy. Wolf and Frey use dendrocalamus strictus bamboo, which is said to be the strongest, most resilient bamboo in the world – in fact, by weight it’s stronger than steel, and very stiff. “If you Google it, it’s nickname is ‘iron bamboo,’” said Frey. “It only grows in southeast Asia, in hot tropical climates.”
Wolf and Frey have one plantation where they source all their bamboo. They only choose plants that are three to four years old, because even though the plants reach full height in just a few months, by this age the walls have become consistently thickened. The bamboo is cut green and then aged for five months in a climate-controlled chamber.
“We have basically infinite tube selection,” said Frey, noting that they screen tubes for imperfections before even cutting the plants. “We pre-stress every tube,” he added, “So if it’s going to break, we break it before it’s built into a frame.”
A treatment process follows, to seal out moisture, and then the tubes are bored internally to ensure consistent wall thickness.
“Every tube on every frame is adjusted for what model it is, and also what frame size it is,” said Frey. “So the smaller frames have thinner tubes so it’s not too stiff for lighter riders.”
Frame construction involves mitering the tubes, then hand-wrapping the joints with individual 12k single-strand carbon fiber threads. “That’s why it takes forever,” said Frey, “but that’s also what allows us to control the fiber layup so we can align almost all the fibers in the load path.” Ahead of time, the tubes are milled at the ends so the carbon joints wind up flush with the tubes, giving the frames a seamless, lugged appearance. The final step is a 3-part German lacquer clear coat.
James Wolf in Vietnam does the frame building by hand, along with four workers. Frey noted that the assembly team is accustomed to building lower quality products in higher volume, with less attention to detail and no credit. They enjoy making high-end, boutique bike frames that land directly in the hands of happy cyclists. The same cadre of bamboo workers has been functioning as a team for years, and with guidance from Wolf, the shop is successfully cranking out both stock and fully custom frames for road, ‘cross, and mountain bikes.
Later this year Frey will be joined in the company by Will Watts, one of the originators of that first bike from Princeton. Of trying to get his company off the ground, Frey said, “It’s really like a 24-7 job, and that’s what Will’s going to do.”
In any case, look for Boo Bicycles at NAHBS, and maybe someday at a bike shop near you.