The late great Sheldon Brown had an excellent article comparing the qualities of various frame materials on his website (not sure about the link). Aluminum "period correct" frames (with the exception of Klein and Cannondale) lacked the tensile strength and stiffness of lightweight steel. The early 80s Klein and Cannondale frames compensated by using over-sized tubing. I test rode both and was recall being disappointed with the ride quality. Modern aluminum frames are another matter - and OT.
Steve Whitting
"The Ciocc Cat"
Prairieville, Louisiana USA
Website at http://ciocc-cat.angelfire.com/
From: Charles Nighbor <cnighbor1@comcast.net> Subject: [CR] Aluminum and life of a frame To: chriseye@comcast.net Cc: classicrendezvous@bikelist.org Date: Wednesday, February 24, 2010, 11:53 AM
The fatigue strength is way below steel. So most aluminum frames are designed with factor built in. i.e. thicker tubes walls than needed. Than has aluminum fatigues for a while frame is less stiff and near what frame should be in terms of ride quality. But after a lot of miles an aluminum frame will become flexible beyond what is desirable for good riding frame. A correct designed steel lugged frames should be good for at least 25,0000 miles. An aluminum should peak out way below that mileage.
And Aluminum frames should be off topic so reply off line
Charles Nighbor
Walnut Creek, CA
USA