By Tom Demerly.
manufacturers love photos of their bikes in wind tunnel tests
and pounding their chests about aerodynamics. But what does
it really mean?
Bicycle advertising is a little like a guerilla
war: The rules are, there are no rules.
Ad agencies and bike companies play fast and loose
with performance claims in a vacuum of oversight. The validity
of an advertising claim seems commensurate with the size of
an ad budget. Advertising budgets are like bullets in a war.
And like a lawless nation, the guys with the guns make the rules.
The consumer is the one left pillaged since, in this Somalia
of Salesmanship it is difficult to tell what is really true.
As a result we bike buyers often can’t tell
what we’re really buying or how it really compares. Which
bike is the most aerodynamic? Which bike is second? How can
we tell? What constitutes good bicycle aerodynamics and how
much do frame aerodynamics really matter for the rank and file
age group triathlete?
I was on the ground for 9 hours at this year’s
Interbike Bicycle Trade Show in Las Vegas, Nevada. Part of the
reason for my visit was to locate the second most aerodynamic
bike available in the industry. I had given up on the most aerodynamic
bike since no less than six manufacturers assured me it was
the bike in their booth. Only one manufacturer conceded having
the second most aerodynamic bike at Interbike, but only after
telling me their highest end bike was the “most”
If six bike companies were telling me they all
had the most aerodynamic triathlon frame at Interbike then five
of them are lying. How do we tell who?
Statistically that means, if a salesperson is
telling you the frame they are selling is the most aerodynamic
of those six brands there is an 83% chance they are wrong. Those
are pretty bad odds.
You don’t have to be Geraldo at Interbike
to figure out a lot of these bike guys are playing fast and
loose with the facts. We need an impartial consensus separate
from the profit motive of selling one brand over another before
we’ll likely find the truth.
Even if we did get an oversight committee or board
of consensus on bicycle aerodynamics, how important is bike
aerodynamics to the rank-and-file age grouper anyway? (More
on this toward the bottom). In a weird brand of fixation, and
perhaps due to a lack of real facts in other areas, consumers
seem scope-locked on aerodynamics as the single most important
feature of a bike.
In any capitalist endeavor equality and standardization
are profane words. Uniqueness and differentiation are the goal,
the holy grail of achieving the competitive edge. As a result
any attempt at standardization carries with it the feel of excessive
regulation. There is a list of specifications for designing
a competitive bicycle imposed on the sport by the U.C.I. and
other governing bodies. If it weren’t for those rules
we’d be pedaling on our backs or stomachs inside something
that looked like a giant sex aid. We’d be faster, but
it would be a different sport.
Standardization is an ugly word when there are
competitive interests afoot, be they athletic or sales interests.
Our sport is plagued by an amalgam of both of those agendas.
Ultimately though, there would be advancement through a common
understanding of bicycle aerodynamics separate from a sales/profit
Right now there are a few ways to make money with
a bike design. One way is to have the fastest design. In the
empirical world of science this would prevail. But enter the
hazy world of the sales motive and other agendas complicate
the equation. If sales and profit are also the motive then having
the least expensive, easiest to manufacture aero frame design
may trump plain old aerodynamics as the profit leader. For you
and I the finish line is marked by a clock that measures success
in hours, minutes and seconds. For bike companies the finish
line is a horizontal line across the bottom of the last page
on a financial report. That is where the problem lies.
We need a way to make the finish line the bottom
line for bike companies. Who will do it?
In the dark ages of triathlon bike design a White
Knight emerged. After founding and ruling a kingdom, the first
“Kingdom of Tri-bike-ia”, named for the land of
Conquistadors on the Mexican coast (really!), he took to the
wilds to wander the deserts while others pillaged and profaned
the kingdom he built. These were dark times of ever slackening
seat angles and dubious bike designs. But the White Knight wasn’t
kept down long, and from his desert stronghold he reached out
with the magic powers of the Internet and united the true believers
with the Rosetta Stone of triathlon bike geometry: Stack and
For the uninitiated “Stack and Reach”
are a simple and elegant method of standardizing triathlon bike
geometry and fit. It is a language spoken around the world.
It empowers the down trodden consumer to make an educated decision
about what bike they are buying and how it will fit. If you
buy into the idea that bike fit is the single most important
factor in bike performance then this single document, the “Stack
and Reach” charts for triathlon bike manufacturers, is
the Rosetta Stone. It sorts through all the baloney, all the
marketing, all the photos of lithe, well muscled men and women
grimacing on shiny bikes in howling wind tunnels. Dan Empfield’s
simple “Stack and Reach” empowers fitters and consumers
to make meaningful comparisons of bike fit from brand to brand.
What we need is a “Stack and Reach”
for the windtunnel: A standardized test protocol arrived at
by consensus and agreed upon widely enough to be considered
credible. If we had this tool for making aerodynamic comparisons
we could make more informed choices about which bike to buy.
Our decisions would be governed first by Stack and Reach and
then by an amalgam of empirical data from the Independent Bicycle
Windtunnel Consortium- or whatever it was called. Oh, those
things and our favorite color…
A consensus on what makes a bike more aerodynamic
likely strikes terror into the hearts of current bike brand
product managers since it may mean they would be hurling expensive
bike tooling and molds into the scrap heap and having to go
back to the drawing board when they find out their “best”
aerodynamic design has the drag coefficient of an upright mattress.
All those fancy photo shoots in the wind tunnel would be exposed
for what they are: Good theater.
The eventual outcome would be faster bikes for
you and I and an easier shopping experience. We’d leave
the bike shop knowing we got a reasonably aerodynamic bike that
fit correctly. The rest would be decided by bike fit and position,
training, mechanical issues and wheel selection.
For most people I think bike buying involves a
process of trying to grasp something we can believe in: Should
we buy into manufacturers claims of aerodynamics? Is bike weight
the primary determining factor in what is best? How important
is bike fit anyway? What about components? It is a confusing
decision with little consensus.
When I talk to consumers about their bike shopping
they tell me they are doing “research”. The term
“research” suggests an orderly and empirical process
of evaluation and selection. It all seems very sentient and
orderly, like Mr. Spock feeding the bike brands into his Tricorder
and then buying the one determined to be the most logical. It
isn’t like that.
People may like to believe they buy bikes like
that, but they don’t. “Research” when buying
a new bike often starts as an attempt to gather some basic facts
to compare bikes then lapses into frustration since there is
little standardized information. Then “research”
defaults to justifying the purchase of the bike we think looks
There isn't anything wrong with factoring in emotion
when buying a bike. I do it, we all do. For most of us bikes
are like sports cars, we really don't need them, but they are
fun to have. It does take a bit of a turn when you miss your
first age group trophy by four seconds. Then it starts to become
more serious. Then we want some Mr. Spock to help us buy those
four seconds back. I think it is a healthy and noble pursuit-
going fast and doing the best we can.
If we had a “stack and reach” type
standard for bicycle aerodynamics it would take one more variable
off the table. As an industry it would likely sell more bikes
since it would emphasize the advantages of having an aerodynamic
bike frame separate from a glitzy sales motive. Standardized
wind tunnel testing would also challenge the industry to build
better product and likely make the customer focus on other issues
that would influence performance like bike position and training.
If we had a standard wind tunnel test for
bicycles we could make meaningful comparisons from one bike
brand and model to the next. Bike buyers would have more confidence
in their buying decisions. An emphasis would be placed on design
at the manufacturer level with a standard yardstick for manufacturers
to measure their products. All of us would understand what we
are buying and we’d spend less time buying it and more
time riding it. Then we’d all be on the same sheet of
music about bike aerodynamics and we could focus on training
and racing instead of trying to cut through all the marketing
baloney and phony wind tunnel tests.