Originally Posted by teterider

Wrong!! Cannondale actually worked with Alcoa to develop the Optimo aluminum when they dropped the 6061 they had used for a long time. They in fact were very involved with the aluminum development and testing. Optimo is actually a proprietary and special 6000 series.

Quote:
"Optimo aluminum was developed in a partnership with Alcoa and was introduced to the market in 2002 with the CAAD7 road frame. The development process of the specific elements of the alloy took over 18 months, and Cannondale has exclusive use of this alloy in the bicycle industry."

They found 7000 series, while light, is too brittle and it failed their torture tests. The Ridley is 7000 series.