There’s no TYPO on the TITLE although many of you probably read POWER TO WEIGHT RATIO. That’s what we expect to see – hear because that’s what we always see and hear. POWER TO WEIGHT. It’s physics very pure and very simple.
Right behind WEIGHT is AERODYNAMICS. “AERO IS EVERYTHING” as coined by SPECIALIZED recently. No doubt as speed increases AERODYNAMICS certainly moves up the list on things that slow you down. On a flat road air resistance can equate to 70-90% of the power required to maintain a given speed. 
For example if you’re a 175 pound rider pedaling at 20 mph on a completely flat road and there is zero head wind [no cross either] you’ll need about 95 watts of power to maintain that speed. Now same riding and conditions and you crank the speed up to 30 mph and the wattage needed to maintain that leaps to just over 317 a threefold increase.
When we’re pushing the envelope we are really talking about two categories: THE MASS and THE MACHINE.
The MASS includes everything that must move: you, the bike and all you’re both carrying.
The MACHINE is the engine that moves it. That means YOU. Every fast and slow twitch muscle, every metabolic pathway, every energy system, every input and output and the WILL of the driver.
There are clearly LIMITS to both MASS and MACHINE. UCI sets limits on the minimum weight of the bike and to some degree on the aerodynamic efficiency. Even experimental bikes have limits according to what design strength and materials will allow. Riders too can only “contort” so much for minimal drag and still maintain power.
The machine – the rider can be properly FUELED properly HYDRATED and properly MOTIVATED under certain conditions.
But here again there are limits. MINIMUMS and MAXIMUMS that despite everything else being finely tuned will become the RATE LIMITING factor.
It is well established and a common experience that we don’t ride as fast, far or as well in the heat as when in cooler conditions. Depending on the study “Gross Efficiency” [GE] in cycling can drop by as much as 17-25% when riding in hot and/or humid conditions. .
The reasons for this are multifaceted and as controversial in their exact causes as they are lacking for effective solutions.
We can say this about the heat and overheating, to some “DEGREE” [pun very much intended] the HEAT effects everything about the MACHINE – you. The physiological consensus statement on the subject is this:
“The harder your body works to cool itself, the faster you fatigue.”
So when you’ve PUSHED the ENVELOPE on the MASS and you’ve done all you can to FUEL and HYDRATE the MACHINE there’s only ONE THING LEFT TO DO.
COOL IT DOWN.
We guarantee you won’t believe the difference 15-20 degrees cooler can make on your POWER TO HEAT ratio.
Try “A Cooler Way to Ride” risk free for 30 days. If you’re not completely impressed and cooler we will refund your purchase.
 https://www.exploratorium.edu/cycling/aerodynamics1.html Wind resistance calculator
 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2039810/ Gross Efficiency [Cycling] is reduced in the heat