Originally Posted by
PeteHski
I disagree. It depends on your riding goals and the specific bike in question. At 6' tall I'm often in between a large and medium frame and usually go with large. Why? Because I'm primarily an endurance rider and prefer the inevitably longer wheelbase and higher stack of a larger frame size. If I was racing crits I may well choose to size down for a more aggressive position with slammed, super-long stem. But that's not how I want to ride all day.
But I totally agree at 5'9" I can't think of many Large frames that would work well. I would have thought the OP was a medium without much question.
I think if you look at the geometry of the Tough Road he's talking about, it's more than possible a large frame could work for him.