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 2014. 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 (66 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.
How did we do? Consider this 10 page feature. Please read this review of our Dragonfly published in the June 2011 issue of Road Bike Action. Zap, Editor of Road Bike Action, picked our Dragonfly as Bike of the Year in their January 2012 issue. On the heels of this honor, they asked us to build the frame module, a Calfee Adventure, for a gravel road project bike; the 10 page feature was published in the October, 2012 issue and the results are in; RBA editor Neil Shirley won the King of the Mountains competition and second overall in Crusher in the Tushar aboard this Dragonfly Adventure. Here is a link to complete coverage of the bike, rider and race. This video captures Neil and the balance of the Pro field throughout the difficult day; rain, gravel, altitude…
This video captures a 15 pound Dragonfly with Di2 on the roads of Texas. The bike also features our full-carbon BarStem, a PressFit 30 BB shell, painted logos as well as a new stock color for Calfee, pearl white metallic.
Dragonfly single and tandem lugs are pressure molded from high modulus fabric. With Dragonfly singles, lugs are made with carbon fabric formed around metal mandrels. These lugs and pre-mitered tubes are easily bonded together because they are so compatible. The carbon fibers are carefully oriented to put strength exactly where it’s needed while minimizing weight. Gussets are integrally formed with the fabrication of the joints, eliminating the inherent weakness of the tube and lug joint found in many other manufacturers designs. They are then meticulously carved to the optimum shape, taking into consideration the weight and intended use by the rider. They happen to look good because of their form-follows-function aesthetic.
The dropouts are also carved out to their optimal shape, saving 15 grams off the standard dropouts. This may not seem like much, but the way to build a 12 pound bike is to address every component and look for opportunities for weight savings, no matter how small. The trick is to do it without sacrificing strength and durability. As in nature, the Dragonfly is one of the most optimized and evolved structures to be found.