PROVO In 1817, Germany's Baron Karl von Drais invented a two-wheeled device that helped him get around his royal gardens more quickly.
Made entirely of wood, the "Draisienne" or "hobby horse" was bulky, cumbersome and quickly ran its course as an impracticable fad. A forerunner to the modern bicycle, von Drais' invention has been improved on many times during the past two centuries and has been again, this time by a group of Brigham Young University engineers.
Variations of von Drais' invention have surfaced with the passing of time. Consequently, with each addition came additional weight. Not until the 1970s did bicycles start to lose weight with the advent of the 10-speed bike.
As bikes have grown up and slimmed down the biking industry has made a science of what was once a simple mode of transportation. For instance, aerodynamics is as much a part of a bike as its size and weight. It's not just a matter of getting around, it's a matter of how quickly and adventurously a person gets around.
The engineering students at BYU have developed a bicycle frame that may soon have a huge impact on the cycling world. Lighter, more aerodynamic and less fragile than its contemporary counterparts namely the mountain bike the ultralight IsoBike is made of carbon fiber intertwined with Kevlar string and uses technology that has only been used previously in larger structures.
The bike frame uses BYU civil engineering professor David W. Jensen's IsoTruss technology, which has previously been used in structures such as meteorological instrumentation towers and self-supporting utility poles. IsoTruss is a cage-like, open tubular lattice that uses the natural strength of supporting pyramids and triangles to achieve the strength of steel at a lighter weight. IsoTruss Structures Inc., a Brigham City-based company, purchased the rights to the technology in 2002.
Several years ago, BYU engineering students had the idea of using IsoTruss in a bike frame, but the difficulty of constructing IsoTruss on a much smaller scale than had been previously attempted proved to be problematic. Manufacturing engineering student Tyler Evans joined the efforts about four years later and has had a key role in the project's recent success.
Prior to Evans' joining the team, there had been three versions of the IsoBike, none of which met the goals of size and durability. Though technically IsoBike IV, the current prototype is referred to as IsoBike I within the group because it is the first version that has reached the group's goals.
The bike was taken to the International Bike Show in Las Vegas last October and, though not technically a part of the show, drew the attention of several companies.
To test its durability and marketing feasibility, IsoBike was sent to Specialized Co., an industry leader in the bike business, to test in its California laboratories. After being subjected to tests that are used in the development of its own bikes, Specialized reported that IsoBike performed very well.
In addition to its unique look, IsoBike is lightweight, weighing 3 pounds, a number Evans hopes to see decrease soon.
"We're confident the next one will be less than 3 pounds," he said. "That's a big deal in the cycling world."
For quite a while, being a big deal is what stood in the way of achieving the goal of making a bike frame using IsoTruss technology. Because IsoTruss had only been used in large structures, using the technology on a much smaller scale was the group's biggest challenge.
"The team's goal was to shrink the IsoTruss structure, which has been proven to work well for large-scale applications, from between 5 to 18 inches to about 1 inch in diameter," Jensen said. "Everybody involved has done a great job of accomplishing just that."
Just where IsoBike technology is headed is undecided right now. Several undisclosed bike companies have expressed interest in the bike. The possibility of starting an IsoBike company has also been discussed. Ultimately, the BYU technology transfer department will decide IsoBike's future. Several private investors have also expressed interest in IsoBike.
There is an important difference between mountain bikes and road bikes. Mountain bikes require a much firmer frame in order to endure the rigors of mountain biking while road bikes require less firmness and bulk. Because of this, mountain bikes are naturally heavier than are their road bike counterparts.
Currently, there are only two bike frames on the market that weigh less than 3 pounds. These lightweight models, however, carry a rider weight limit of less than 150 pounds and lack the rigidity needed for long-term mountain biking. Evans is confident that IsoBike will be free of these restrictions. Most lightweight mountain biking frames, however, weigh in between 2.8 and 3.5 pounds and run as high as 5 pounds.
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