Showing posts with label time trials. Show all posts
Showing posts with label time trials. Show all posts

31 March 2016

Aerodynamics Or Weight?

Ever since I wrote yesterday's post, I have been thinking about weight and aerodynamics. 

For decades, cyclists have debated which is more important.  Actually, when I first became a dedicated cyclist four decades ago, there didn't seem to be much talk about aerodynamics.  Then, the emphasis was on weight.  That makes sense when you realize that many new cyclists--myself included--noticed how much lighter those newfangled (or so we thought) ten-speeds were than the three-speed "English racers" or balloon-tired Schwinns and Columbias we and our parents had ridden up to that time.  We went faster on those new "lightweight" ten-speeds; racers raced on them (or bikes that looked like them).  Ergo (that wasn't yet the name of a brifter), light weight must equal speed and all-around performance.

The tuck


At that time, about all that most cyclists knew about aerodynamics regarded their own position on the bike.  We all knew that the "tuck"--in which a cyclist rides as far forward as possible with his or her arms and legs as close to the bike as he or she can pull them in--was the most aerodynamic way to ride.  Oh, and we thought that shaving our legs would cut down on our wind resistance.

Little did we know that around that time, engineers and scientists like Chester Kyle were experimenting with ways to make the bicycle more efficient.  An experiment to find out whether tubular (sew-up) tires were indeed actually better than clincher (wired-on) tires led to a research that culminated with the development of streamlined bicycles, fairings and recumbent bicycles.  It also was instrumental in helping to create much of what we see (and some of us ride) today, such as disc wheels.

At first, only he and fellow members of the then-newly-formed International Human Powered Vehicle Association (IHPVA) seemed interested in his work.  Part of the reason for that is that bicycle racers, especially at the top levels, were reluctant to change equipment that had been working for them.  Even if riders were more willing to experiment, there was the spectre of the Union Cycliste Internatonale (UCI) (yeah, those guys again!), which had a history of declaring records null and void if its members believed they had been set on bicycles that deviated much from prevailing standards.

But, slowly, racers started to take notice and a cottage industry developed in aerodynamic bikes and parts.  The first attempt to bring aerodynamics to a wider audience came in 1981 when Shimano introduced its Dura Ace AX components.   Shimano's motivation for creating and marketing such a group of parts had, not doubt, had at least something to do with its desire to challenge Campagnolo's then-near-monopoly as a supplier for the world's top racing bikes.  It also had to do with its desire to distinguish itself from other component manufacturers--including SunTour--in the eyes of consumers. 


 
Shimano Dura Ace AX Components, 1981


But Shimano didn't get the payoff it had hoped for.  Most consumers, accustomed to the aesthetics of Campagnolo and the new SunTour Superbe components, didn't like the way AX stuff looked.  Also, it was heavier than what either of those companies made, as well as Shimano's conventional Dura-Ace components, and more expensive.  Most cyclists wondered just how much of an advantage they would gain by using aerodynamic components.


At that time, I knew a few cyclists--racers and the well-heeled--who used the AX stuff, usually on bikes like the Miyata Professional.  They all swore by the parts, and the bikes.  Mind you, they were the sorts of cyclists who believed that nothing could be better than an Italian (or, maybe an English or other European) bike with Campagnolo equipment.  Convinced as they were, though, they never seemed able to convince others to switch.

Laura Trott riding with disc wheels.  Oh, she won the gold medal.


Around that time, the first disc wheels and "deep V" shaped rims started showing up.  They, like the AX components and Miyata Pro, had their devotees, but could not convince others to make the switch.  The reservations expressed were the same:  looks, weight and cost.

(I must confess that I was one of those who didn't switch.  As my budget was very limited--I skipped meals and such to afford my Campy stuff--I simply couldn't afford to buy new parts.  Also, because my budget was limited, I was reluctant to try anything new or experimental.)


While the needle didn't move much for most cyclists, gradually time trialists and track riders started to adopt the new aero equipment.  Those probably were the disciplines in which the aerodynamic equipment made the most sense:  In the peloton, or in any other large group ride, you could probably be more aerodynamic just by riding within the group--or simply "drafting" one rider. 

Interestingly, the group of cyclists who did the most to make aerodynamic equipment desirable for others were triathloners.  Perhaps this has to do with the fact that the cycling portion of the triathlon more closely resembles a time trial than a road race, in part because there is no drafting. Also, riding in a more forward position takes weight off riders' legs, which leaves them fresher when the triathloner has to jump off the bike and start running.

It was for the triathlon that the first widely-used aerodynamic handlebar, the Scott DH, was developed. They made the "leap" into pure bicycle racing--as I noted in yesterday's post--when Greg LeMond rode them to victory in the final time trial of the 1989 Tour de France, which enabled him to win the whole event.

Greg LeMond riding to victory.


One thing I remember is that my Cinelli Spinacis added about quarter of a kilo (a bit more than half a pound) to the weight of my Colnago.  And the Spinaci was one of the lightest aero bar extensions available; others added as much as a full kilo to the bike.  Other aerodynamic components required more material, and were thus considerably heavier, than their counterparts. As an example, Mavic's 631 "starfish" crankset, which LeMond rode, weighed 723 grams. On the other hand, the company's 630 crank, patterned after the Campagnolo Record series, weighed only 525. For wheels, the weight difference was even greater:  1500 grams for a typical rear road disc of the time vs. 1110 or less for a wheel with 36 spokes, which was still the norm at the time LeMond rode.




Mavic 631 "starfish" crankset


Which brings me to the question everyone asks:  How much did LeMond's Bottechia aerodynamic weigh?  Well, according to the reports I've read, "more than 25 pounds (about 12 kilos) or even "more than 30 pounds" (about 14 kilos, which I find difficult to believe).  The lower figure is be about two to four pounds heavier than a typical road bike of the time; even if we go by that, we see that you don't ride an aero bike or components for the weight savings.



The bike LeMond rode in the last stage of the 1989 Tour de France.


So...the question remains:  Which is more important, weight or aerodynamics.  If I were a time trialist, I would certainly worry more about the latter. And for climbing or any kind of riding that requires quick acceleration (or deceleration), light weight is more beneficial.  For everyone else:  I don't know what to say.  And as for me: I don't worry about either.