Originally Posted by
HTupolev
How big of a discrepancy were you looking for, and how much precision did your testing have?
The speed advantage of latex tubes over butyl can be on the order of a couple tenths of a mph. It's very good as a performance-per-dollar change as road bikes go, but still small enough to require at least mildly careful testing to discern.
My first reaction is that "a couple of tenths" was too high. But on this
bike speed calculator, taking defaults, but in the drops, 250 watts=23.2 mph, 260 watts=23.5. 0.3 mph faster if the rider saves 5 w per wheel. More than I guessed. I'm thinking that latex vs lightweight butyl is 3-5 watts savings.
Over 25 miles distance, 20 mph vs 20.1 mph is 22 seconds. Hard to notice in real life, a big deal in a race.