Forgive me, Dale, if this is an off-topic post. I think it could pertain to any vintage.
Here is a link to an article from Design News, June 2010 about "Fracture Mechanics and Bicycle Pedals".
You may have to copy the whole link and paste it into your browser. You could, also, navigate to http://www.designnews.com, find the archive table of contents, select the June 2010 issue and search for "fracture mechanics". The first reference will take you right to the article. I could also scan it for anyone that has difficulties.
Orange, CA USA