Here is an interesting article that bears out something I have been saying for years. That the weight of a bike has little bearing on the performance, even when climbing hills, even though simple physics tells us that a heavier bike should be slower.
Bicycle Quarterly did a controlled test with two riders climbing a hill, one on a 17 lb. titanium frame and the other on a 26 lb. steel randonneur bike. That is a whopping 9 lbs. difference and yet these bikes consistently climbed side by side at the same rate even with different riders.
The randonneur bike also has mudguards and a handlebar bag that must increase drag. So clearly the rider on the randonneur bike is putting out more power, enough to offset the huge weight difference. Is this possible?
Apparently so. In another test Bicycle Quarterly did they compared two bikes weighing the same but with different frame tubes.
In this test, with the same riders switching bikes, the same one bike was consistently faster. Power Tap meters were used to measure each rider’s output. On the faster bike one rider put out 5% more power than he did on the slower bike, and the other 2% more.
The author of the above linked article points out that it is difficult to reach maximum heart rate on a bike, unlike running which of course is much harder. He surmises that if the muscles can’t use all the oxygen that the heart is pumping to them, why should the heart beat any faster?
If one bike or bike frame leads to the rider becoming fatigued at a faster rate, the power output for that bike or frame will be less.
Back in the early 1980s when I was building my custom ‘dave moulton’ frames, I made a “Road” frame built with Columbus SL tubing, and a “Criterium” frame made from the heavier and stiffer Columbus SP tubing.
People who bought the Criterium frame told me all the time, “This bike climbs like you wouldn’t believe.” Many different people, of all different riding abilities, all said the same thing.
Another typical comment Criterium frame owners would make, “This bike kicks my ass… I can’t help but ride fast and I come back from a ride knowing that I have had one Hell of a work-out.” Clearly the stiffer, even though heavier Criterium frame caused the rider to put out more power.
All frames I built were stiffer than many production frames in the same material, because I put less heat into the frame. Many larger manufacturers used conveyer style production lines with gas flames to pre-heat the frame before it reached the person who would braze the joint.
Heating a tube in this way means it is glowing red hot several inches from the lug, thus removing much of the tube's inbuilt strength. Working quickly using a smaller but hotter flame I heated the tube barely a quarter of an inch from the lug.
Terry Shaw who was the owner of Shaw’s Lightweight Cycles, and a bike dealer who sold more Fuso frames than any other, coined a phrase that was part of his sales pitch. He always said "The Fuso climbs lighter than it actually is.”
So rather than looking for the lightest bike, people should be looking for the one that enables the rider to put out the most power. Because isn’t the whole object of a road bike to go faster if you are racing and to get more of a work out if you are training or riding for exercise.
Manufacturers of bikes for professional riders should be researching this. Although always it is the rider, not the bike that is faster; it seems highly probable that some bikes make better use of the rider’s output, and may even cause the rider to increase his output.