Expert Explanation: Steep v Shallow Angle Tri Bikes

This is a subject that is often discussed alot on this forum but I think alot of the discussions assume a level of expertise that most of us don’t possess (and some fake). I think many of us are in need of someone who can explain (in terms that a layman can understand) the following:

The difference between a steep angled bike and a shallow angled bike? What does the angle refer to and how can it be measured? What are the benefits (and disadvantages) of a steeper angled bike? What type of rider usually benefits from a steeper angle (large/small, good climber/bad climber, flexible/inflexible, etc?) What degree is considered steep, what is shallow (average road bike, I guess?) and what is in the middle? What are the best ways to increase (moving seat up and forward?) or decrease the angle to see what’s best for you?

Anyone?

First read this. Then go on the tech section on the Slowtwitch main page and read Dan’s articles.

http://www.bikesportmichigan.com/bikes/difference.shtml

As this article explains, there’s a lot more to steep/shallow than just seat tube angle:

http://www.fitwerx.com/NewFiles/Tech%20Center/BicycleGeometry.html
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