Joined: Feb 2012
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From: Rochester, NY
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
Originally Posted by
Ironfish653
The 1997 Cannondale F-1000 and the 1976 'Techniart' Bridgestone in my garage would like to know what that finite life is.
The Dale is a retired XC racer, and 3x week commuter. The Bridgestone did some touring BITD, a couple of audax events the last few year and is now retired to 'Townie/Path Bike' oh, and pulling the tag-along.
They're concerned that they don't have much time left. I weigh ~200# Should I scrap my bikes?
"
Ferrous alloys and titanium alloys[2] have a distinct limit, called the endurance limit, which is the amplitude of completely reversed bending stress below which there appears to be no number of cycles that will cause failure. Other structural metals such as aluminium and copper do not have a distinct limit and will eventually fail even from small stress amplitudes" https://en.wikipedia.org/wiki/Fatigue_limit
So a steel frame has an unlimited life as long as the stresses are below some threshold and Al will fail at some point no mater what the stresses are. That is why you don't see Al springs as example. Andy
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AndrewRStewart