Bicycle Frame Design

In this section of the module you will be analyzing the forces which develop in the internal members of a bicycle frame. Bicycle frame designers are aware of a number of factors which affect how the rider's forces are carried by the tubes. Discuss the following questions with other students as you try to understand what the factors are that affect the design and subsequent performance of bicycle frames.

In your experience, do all bicycle frames look the same? Why do you think there are so many different designs? How significantly does the geometry of the frame affect the loading? Which tubes do you think normally carry high forces? Are all of the bicycle tubes the same size and shape?

What might be a possible simple method that you could use to analyze the forces that develop in bicycle tubes? What type of structure does a bicycle frame resemble?

As you will ultimately see, the analysis on the next page is performed by treating the bicycle as a truss structure. However, a bicycle frame is not truly a truss for a number of reasons. What are these reasons? To put it another way, what types of assumptions must be made in order to analyze the bicycle frame loading as a truss structure? Consider some of the following:

If you would like more insight into the assumption process, see the Engineering Modeling concept page.

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