Design of Aluminum Bicycle Frames

This paper presents the use of a hybrid stress analysis method for the prediction of fatigue life of bicycle frames. A finite beam element computer program is used to calculate frame stresses. In order to correlate the results with actual frame stresses, brittle coating experiments are conducted on an aluminum frame. Strain gage experiments, guided by the brittle coating results, provide more accurate measurements of maximum principal stresses. Stress concentration factors are defined, the fatigue life of an aluminum frame is predicted for a simple loading condition, and the result is compared with in-service failure data.