Originally Posted by
somebikerider
Does anyone know of any real research on the subject?
Bicycle Quarterly has been doing lots of controlled tests on tires.
The editor is an advocate of wide-ish tires (28 to 32c) for fast, long distance riding...but they have found wide differences between various models.
Back issues available here:
http://www.vintagebicyclepress.com/vbqindex.html