Bicycle Weight

I came across this article on the Torelli website which I thought was interesting:

"Bicycle Weight, the Benefits Quantified"

Everyone talks about bicycle weight. It consumes our discussions.Magazine reviews make it clear that if the very lightest parts are notchosen, if it is not as light as possible, the bicycle being examinedis suspect. Light weight has become the sine qua non of a goodbicycle. A light bicycle is a good bicycle, without any furtherdiscussion 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 handyavailability of a single number has led people to make poor decisionsin their choice of bicycle.

First of all, weight is important. If it weren't, we would all beenjoying pleasant 75-mile rides on 42-pound Schwinn Varsity bikes. Theroad bikes offered today are a far cry from those mild-steel tanks.We're not talking about riding heavy bikes. I want to limit thediscussion to modern, well-made, well equipped bikes.

My personal favorite bike is a 55-centimeter all Columbus Foco SteelTorelli bike with a steel fork, generously chromed, built up with aCampagnolo Record 10-speed group. It weighs about 19 pounds. Beyondaluminum spoke nipples and double-butted spokes, there is nothingheroic about the equipment to make it lighter. The Squadra HDP saddleis heavy by the usual standards.

UCI regulations limit a racing bike to about 15 pounds. What we arediscussing, from a normal all-steel bike to a super-light, barelylegal bike is about 4 pounds. This is what we're going crazy about, 4pounds. 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, thedifference is obviously very small indeed.

But how does this weight difference affect performance? Does removingthese few pounds make the bike fly? Is a lighter bike the fountain ofyouth? The September 2003 Bicycling Magazine has a chart that makes iteasy to quantify the performance gains from light weight. James C.Martin, Ph.D., assistant professor in the department of exercise andsport science at the University of Utah provided some interestingcalculations that make the cost of weight very clear.

He posited a 5 kilometer, 7% grade. That's a good, stiff climb. Thelegendary Stelvio climb averages 7.5%. He further assumed a rider whocan kick out 250 watts. A 160 pound rider will take 19 minutes and 21seconds to get up the hill. Every 5 pounds added make the trip up thehill take 30 seconds longer.

That means each added pound adds 6 seconds to the time it takes to getup 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 asuper-light carbon or aluminum bike, the time difference up this hillwould be 24 seconds from best to worst.

But, most weight conscious people aren't bringing their bikes down to15 pounds because down at that weight, the handling gets very sketchy.17 - 17.5 pounds is the normal range. The real discussion is about 1.5to 2 pounds.

The performance advantage of a lighter bike is greatest when the hillis steepest. What happens as things flatten out? Then, as the speed ofthe bike increases, the resistance comes from the wind, tire rollingresistance, bearing drag, etc. Those 6 seconds/pound grow eversmaller.

The variations in body weight, however, being so much greater, makelarge difference. If that same 160 pound-250 watt rider were to be 220pounds, 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 notsomething he can give up. No matter what the quality of the ride ofthe bike in question, he must seek every attainable performance gainin his equipment or his body.

Then there is the large body of dedicated cyclists who enjoy the sportat 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 simplequantification. It's not a matter of a 73 degree head tube or 18pounds or 9 sprockets in the rear. It is the whole bike, taken as awhole that must be considered. One should not pick a bike as if hewere one of the 7 blind men describing the elephant.

The fact that these 1.5 - 2 pounds are so unimportant in choosing abike should be looked upon a truly liberating. Now we can to back tojudging 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 tothe competitive advantage of the bike. A full carbon fork replacing asteel fork can take off a little less than a pound. Remember, that'sour 6 seconds. Clearly, we have all been oversold on the carbon forkas the easy performance upgrade. There is some improvement, but it isminuscule. 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 tokeep up me with on a climb."http://www.torelli.com/tech/weight.shtml

I recommend this site for all bike racers and lovers

Bikes which in actual fact (weighed on your scale, not in a marketingadd) get down to 15 -16 lb range (forget about UCI illegal and pie inthe sky sub 15) are going to require a 2lb frame, which meansexpensive carbon or a Litespeed Ghisallo. Try finding one of thosefor less than $2500 or $3000, frame only. When you add your CampyRecord Carbon and your Zipp wheels, etc., your 15 or 16 lb bike can'tby definition can't cost you less than $4500 total - as a practicalmatter much more. A boatload of cash for that 1.5 lb. Somebodyplease do the cost/ benefit calculations.