Half-fast Cycling Club

One of the things folks who don’t do science sometimes misunderstand about it is that we don’t always get things right the first time. Sometimes what we see (like that earth is the center of the universe and everything revolves around it) is wrong – or at least our interpretation is. Beliefs can stay the same forever with nothing to back them up, but as new data are found, science changes.

Bike racers once believed that smoking a cigarette before a climb would open up your lungs, improving your aerobic capacity and making you climb faster.

Then it was believed that wider handlebars opened up your chest wall and gave your lungs more room to expand, with the same result. I once test rode a bike at a shop that set up all bikes with 44 cm handlebars for that reason. It felt weird. I shopped elsewhere. Now the trend is toward ever-narrower bars for improved aerodynamics. There is a UCI ( Union Cycliste Internationale) regulation to prevent using bars that are too narrow (which would make a bike hard to control).

In the bicycle world, most research centers around racing, and the findings eventually trickle down to bikes for ordinary folks…or else ordinary folks who don’t consider themselves ordinary spend big bucks to get the latest and greatest. Unless your name is Tadej Pogačar or Demi Vollering, or you’re chasing them, maybe you don’t need a new bike every year.

You’d think that the skinny tubes on a steel-framed bike would be more aerodynamic than the fatter carbon fiber frames but no, since carbon fiber can be molded to any shape, the fatter but sculpted frame is more aerodynamic.

Once, lighter was better. UCI came out with a minimum weight to prevent building bikes that were so light they might break apart under hard cornering or disintegrate in a crash. There’s a class of bikers known as “weight weenies” who shave every gram they can to make a light bike.

But now, with the detailed measurements available in a wind tunnel, it has been found that a more aerodynamic frame is faster than a lighter but less aero frame. Bikes have gotten heavier again – disc brakes have something to do with that. But do you ride fast enough for improved aerodynamics to matter? Maybe you should just see a cosmetic surgeon and get your body made more aerodynamic. I actually found a tech writer who admitted this, saying “It’s always worth remembering that between 70 and 80% of your drag comes from your body, not your equipment, so maybe that’s food for thought…”

Does this mean anything to you and me? The term “marginal gains” is all the rage. The idea is that all of the big gains have already been found and now incremental improvements can make tiny differences. Each year something changes incrementally. It might make the elite a few seconds faster over 200 km. It might not matter to the rest of us.

It was once thought that the skinniest and highest pressure tires were fastest. Tires were nominally 700x18c at 120 PSI. New research shows that a skinny tire at high pressure tends to leave the ground by just a bit on rough terrain. That momentary slight loss of traction slows you down. Some pros are now running 700x30c at 50-60 PSI. The larger tire at lower pressure acts as a shock absorber. That also saves your back, shoulders, and hands.

But was this always true and previous science was wrong, or is a reflection of lighter and stiffer (less vertically compliant) frames? Are skinnier and higher pressure tires still right on your old bike? One article I read reports that all of the difference in shock absorption comes from the tires and the seatpost and almost none from the frame – so wider and lower pressure tires are better for everyone. But of course, there are limits. If you’ve ever ridden with a tire going flat, you know it feels like a worn-out mattress and you keep getting slower.

Rolling resistance has also been shown to be reduced with wider tires. It used to be thought that the skinnier the tire and the higher the pressure, the lower the rolling resistance.

Crank length used to be based on leg length. The longer your legs were, the longer the recommended crank length. A few pros switched to much shorter cranks. Now that is all the rage. I’ve read a few articles purporting to be about the science. I have not yet read the underlying papers. The summaries don’t appear to take leg length into account. They just talk about crank length with a bunch of subjects.

If you’re considering shorter cranks because Jonas Vingegaard rides shorter cranks and he’s fast, I’d read the actual studies before dropping big bucks. He was faster than you and me before he switched to shorter cranks. I found an article by Lennard Zinn (a framebuilder and tech writer) which starts by saying “First off, you are not going to measurably gain or lose power with a change of a few millimeters in crank length. For people asking about ‘shorter’ cranks, I ask, ‘shorter relative to what?'” The rest of the article requires a subscription.

Pros are riding faster than ever. One reason might be hydraulic disc brakes, which brake more quickly and forcefully, allowing you to carry more speed into a turn. Gearing has changed – where you once had (nominally) ten gears, you now have 24 or 26. Wider tires are also credited with more stability to corner at higher speed. And improved nutrition (better drugs? asks the cynic) makes stronger riders who recover faster.

What all of this means to me is that, while my 35+ year old steel bikes may be considered collector’s items, my 10 year old carbon fiber bike is merely considered obsolete. It can’t use disc brakes, it won’t accept wide tires, it wasn’t designed for electronic shifting.

But what this all really means, is that obsession with data tends to interfere with BFUs (Big Fun Units).

And is everything really about science? I vividly recall the day when, after test-riding more than 30 bikes at shops all around the San Francisco Bay Area, I threw my leg over one bike and knew almost before I got out of the parking lot “This is my bike!” I rode off anyway. I alternated between thinking, “I should turn back” and “I don’t ever want to turn back”. After climbing a couple of steep hills to be sure, I turned back. I bought that bike. I still have it. Would science tell me why that was the bike for me, or just BFUs?

Mmmmm

Speaking of BFUs, County Highway M used to be a fun ride around the bigger lake, when you didn’t want to go too far out of town, but wanted a longer ride than circling the smaller lake.

With suburban growth to the north, it became more of a busy highway – a road to avoid except for the brief stretch necessary to get out of town. With the temperature climbing toward (and beyond) 70º F (21º C) a week after the blizzard, it was time to head out of town. A new bike path has been built parallel to Highway M, so I decided to follow it. It goes almost to Middleton before it dead ends. I headed away from town on Highway K, which was much too crowded to be fun. Too many people in cars headed out.

I saw a half-fast friend in his car at the intersection with K. He warned me not to ride to Roxbury. I don’t know why, but maybe that’s where all the traffic was headed. Weekday riding is better. Another benefit to retirement. As soon as I could, I turned off onto a town road. There is still snow in the ditches so I made a quick stop.

Yeah, I know, he’s a bit lumpy and unfinished. I was in a hurry to get back on the road and my feet were getting a bit wet through the ventilation holes in the shoe uppers. Red-wing blackbirds are back. I think I saw a robin, but it was a quick glance so I can’t be certain.

There were plenty of BFUs to be had with a 73 year old body on a 37 year old bike made of steel with downtube shifters, rim brakes, 700x23c tires, and only 14 gears. Yeah, it’s the bike I mentioned above the Camel ad.