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
Editor
Bicycle Quarterly
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