Our lightest and most technically advanced frame. The Dragonfly tube set was designed to build the lightest possible single and tandem bicycle frames without sacrificing stiffness, durability and ride quality. Please read this review of our Dragonfly published in the June 2011 issue of Road Bike Action. We use high modulus carbon fiber (66msi) in all the tubes as well as the lug areas. Previously, a frame built with all high modulus fiber would be too brittle. We incorporated Boron fiber into the three main tubes to add some toughness and compressive stiffness. Boron is an attractive reinforcement because the resulting composite combines superior tensile, compressive and flexural strengths, high modulus, and low density in one system. Combined with the super high tensile stiffness of the carbon, the result is a frame material with the highest stiffness-to-weight ratio on the market.
The use of boron fiber has come of age with its use in our high performance bicycle frames. Bicycle weights have dropped from 18 pounds back in the 1980s to 14 pounds or less in 2010. Much of this weight savings comes with the use of carbon fiber composites. As bicycle companies compete in the arms race to make even lighter, stiffer bikes, safety and durability are pushed to the limit. High modulus (55 Msi and greater) carbon fiber is being used to make stiff yet thin walled tubing. These tubes can be vulnerable to damage from a variety of real world sources. When slightly damaged from a pebble thrown up by a passing car, or an unfortunate event during a group ride or race, a thin walled tube can rapidly degrade to an unsafe condition. Our very popular Calfee Carbon Repair business is evidence of this common failure. Using boron filaments in the tube laminate mitigates this problem by significantly enhancing the tubes structural performance.
Read more about our Dragonfly frames HERE.