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Everyone talks about
bicycle weight. It consumes our discussions.
Magazine reviews make it clear that if the very
lightest parts are not chosen, if it is not as light
as possible, the bicycle being examined is suspect.
Light weight has become the sine qua non of a
good bicycle. A light bicycle is a good bicycle,
without any further discussion of its other merits
or qualities.
Can we step back for
a moment?
Let's get some
numbers. Let us see if, as I believe, the handy
availability of a single number has led people to
make poor decisions in their choice of bicycle.
First of all, weight
is important. If it weren't, we would all be
enjoying pleasant 75-mile rides on 42-pound Schwinn
Varsity bikes. The road bikes offered today are a
far cry from those mild-steel tanks. We're not
talking about riding heavy bikes. I want to limit
the discussion to modern, well-made, well equipped
bikes.
My personal favorite
bike is a 55-centimeter all Columbus Foco Steel
Torelli bike with a steel fork, generously chromed,
built up with a Campagnolo Record 10-speed group. It
weighs about 19 pounds. Beyond aluminum spoke
nipples and double-butted spokes, there is nothing
heroic about the equipment to make it lighter. The
Squadra HDP saddle is heavy by the usual standards.
UCI regulations limit
a racing bike to about 15 pounds. What we are
discussing, from a normal all-steel bike to a
super-light, barely legal bike is about 4 pounds.
This is what we're going crazy about, 4 pounds.
Maybe a bit more with a less expensive groups. In
any case, given the usual rider-bike package of at
least 180 pounds or more, the difference is
obviously very small indeed.
But how does this
weight difference affect performance? Does removing
these few pounds make the bike fly? Is a lighter
bike the fountain of youth? The September 2003 Bicycling
Magazine has a chart that makes it easy to
quantify the performance gains from light weight.
James C. Martin, Ph.D., assistant professor in the
department of exercise and sport science at the
University of Utah provided some interesting
calculations that make the cost of weight very
clear.
He posited a 5
kilometer, 7% grade. That's a good, stiff climb. The
legendary Stelvio climb averages 7.5%. He further
assumed a rider who can kick out 250 watts. A 160
pound rider will take 19 minutes and 21 seconds to
get up the hill. Every 5 pounds added make the trip
up the hill take 30 seconds longer.
That means each added
pound adds 6 seconds to the time it takes to get up
this hill. That is only 6 seconds on a stiff, 20
minute climb.
So, given our roughly
4-pound range from a full steel bike to a
super-light carbon or aluminum bike, the time
difference up this hill would be 24 seconds from
best to worst.
But, most weight
conscious people aren't bringing their bikes down to
15 pounds because down at that weight, the handling
gets very sketchy. 17 - 17.5 pounds is the normal
range. The real discussion is about 1.5 to 2 pounds.
The performance
advantage of a lighter bike is greatest when the
hill is steepest. What happens as things flatten
out? Then, as the speed of the bike increases, the
resistance comes from the wind, tire rolling
resistance, bearing drag, etc. Those 6 seconds/pound
grow ever smaller.
The variations in
body weight, however, being so much greater, make
large difference. If that same 160 pound-250 watt
rider were to be 220 pounds, he would come in 6
minutes, 10 seconds later.
So what do we do with
this information?
There are two basic
groups of riders to whom this is important.
The first is the
serious athlete. A few seconds advantage is not
something he can give up. No matter what the quality
of the ride of the bike in question, he must seek
every attainable performance gain in his equipment
or his body.
Then there is the
large body of dedicated cyclists who enjoy the sport
at various levels, but do not compete in the higher
racing categories. I think this is almost everyone
reading this essay. For these riders, the choice of
bike and equipment should involve a more complex,
qualitative study. Weight is one consideration. But
there are others. How does the bike feel? Is it
stable? Does it fit? Does it have the snappy, clean,
vibrant feel that should be the soul of a great
bike?
These basically
sensuous questions that are beyond simple
quantification. It's not a matter of a 73 degree
head tube or 18 pounds or 9 sprockets in the rear.
It is the whole bike, taken as a whole that must be
considered. One should not pick a bike as if he were
one of the 7 blind men describing the elephant.
The fact that these
1.5 - 2 pounds are so unimportant in choosing a bike
should be looked upon a truly liberating. Now we can
to back to judging bikes on their real merits.
Before leaving this
discussion, let's look at the most common
"upgrade".
A full carbon fork is
considered an upgrade that will add greatly to the
competitive advantage of the bike. A full carbon
fork replacing a steel fork can take off a little
less than a pound. Remember, that's our 6 seconds.
Clearly, we have all been oversold on the carbon
fork as the easy performance upgrade. There is some
improvement, but it is minuscule. And it is not
without its costs in quality of road feel. For more
about carbon, please see my essay on materials.
Or in other words,
Scarpelli, you can't buy a bike light enough to keep
up me with on a climb.
Bill McGann
Torelli Bicycles
From
our "About Italian Stage Bikes" Page:
Are
Steel Bikes Heavy?
NO! Our eyes roll everytime we here some say
"I don't want steel because it is HEAVY."
Our kneejerk reaction to this statement is usually
"Get your brainwashed head out of the
corporate/commercial bike companies fluff and hype
catalog!" That approach
won't endear too many customers however!!! We
find it more constructive to take 5 minutes to
educate you on the current state of frame materials
and their weights.
This topic is best left for in store conversation,
but let us type a few words on the matter.
First off, proof is in the pudding: we've built full
bikes with lugged, steel frames that weigh in UNDER
17 pounds. And NO, they did not cost $6000.
Most of the steel bikes we build weigh in between 18
and 19 pounds. Today's aluminum frames are the
lightest available. There are some exceptions,
but if you want to talk about top-shelf, proven,
stage style frames, this remains accurate.
Aluminum seems to be
the material that has come closest to the goal of
doing what steel does but with less weight. 20
years ago, aluminum was lighter than steel but it
was harsh riding and too stiff. As higher
quality materials and aluminum alloys became
available, tubing manufacturers became more and more
able to make aluminum tubes with a thinner wall
thickness which reduced stiffness and even lowered
weight. BUT, at the same time, steel tubing
benefited from new alloys and advancements in
production and design. Steel tubing is now
much lighter than it had been. Also, frame parts
like lugs, bottom bracket shells, seat collars, etc.
have been slimmed down by new materials and
production techniques to reduce full frame weight
even further. This is proof in our eyes that
steel is still at the forefront of frame material.
If it is "OLD SKOOL" or "RETRO"
or whatever you want to call it, contact Columbus,
Reynolds, True Temper or some of the other steel
tubing manufacturers and ask them why they continue
to spend millions of dollars on R&D for steel
tubes?!
Remember that what
you lose in weight you gain in many other
departments. A light steel frame is 3 to 3.5
pounds. A SUPER light Aluminum frame is 2.5
pounds. So we are talking about .5 to 1 pounds
net difference. If your absolute 1st priority
is building as light a bike as possible, you won't
choose steel. If you want a very light bike
that performs and rides to the highest quality
standard, you will love a steel frame.
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