Quite true. And a certain Irish chap by the name of Sean Kelly made out OK riding Vitus aluminum frames with conventional tube OD's for much of his career. A career which included a GC victory in the Vuelta, four green jerseys in the TdF, two victories in Paris-Roubaix, and seven consecutive victories in Paris-Nice, which should have been renamed Le Coup de Kelly. Not bad on an improperly designed frame, eh?
Vitus, like ALAN, used thicker walls than steel frames, thus the 25.0 seatposts on Vitus and ALAN bikes. More than one way to achieve the necessary stiffness.
Regards,
Jerry Moos Big Spring, Texas, USA
Jan Heine <heine94@earthlink.net> wrote:
At 7:44 AM -0400 5/15/08, Harvey Sachs wrote:
>To me, aluminum tubes in an engineered bike will be larger diameter.
>Just part of the difference between steel and aluminum, if you want
>similar performance.
Many Tour de France stages and even more cyclocross world championships were won on (on-topic) Alan frames, which do not use significantly oversize tubes. Having owned one, I can attest to its excellent performance, which is as good as the best steel bikes.
There are many ways to make a good bike, and aluminum does not need to be oversize to produce excellent performance. To obtain the desired stiffness, strength and durability from aluminum, you can either increase the tubes' diameter or their wall thickness. Alan used relatively thick walls.
Jan Heine
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