Does Weight Matter?

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One of the things I go back and forth with is the question of how much weight matters.  It's a funny thing, because it's the most objectifiable thing on a bike.  Impressions of geometry and handling will vary from person to person, stiffness can be quantified but more is not always preferred for every rider or circumstance, aerodynamics are debated and argued in various ways, aesthetics are a whole other kettle of fish, but put a bike on a scale and there's only one number that's going to come up.  All else being equal, the lower that number, the better. 

In a world where your like or dislike of a certain golf club is as related to its sound as to its performance, and where cyclists may not have the breadth or depth of experience with different bikes to be able to really pin down their likes and dislikes in the way different bikes handle, it's not unusual that people would place a lot of importance on something that is as readily quantified as weight.

On one hand, I think that perhaps the way that weight's effects are calculated to a racing cyclist understate its importance.  Sites like Analytic Cycling allow you to plug in weights versus coefficients of drag so that you can see that, in general, aero does indeed trump weight.  But aero benefits are measured in a static wind tunnel, and as you can see if you look at charts and graphs from various wheel companies, even the wind tunnel benefits are hard to nail down.  Put them on the open road and it gets fuzzy indeed.  You'd have to have your head buried pretty far in the sand to deny that there are valuable benefits available from aero equipment, but to quantify it is rather difficult.  Part of this comes from manufacturer claims - the chuckles about the new aero cranks that save you 20" over a full Ironman course (winning Ironman bike splits are roughly 4.5 hours, so this represents a .1% improvement) were pretty loud.  So it's hard to know just how much benefit you are getting from aero equipment.  You know you're getting some. 

On the other hand, the static way in which weight is measured probably understates its practical effect just as the wind tunnel likely overstates practical benefits of aero gear.  Most calculations talk about static grade, constant speeds, etc.  That doesn't line up at all with most of the climbing experience I've had - grades constantly change, attacks come and go, etc.  Even on flat courses, you are constantly changing speeds.  I'm guessing that the difference between say a 1500 gram set of wheels and one a quarter of a pound heavier will leave you with more than .1% extra in the tank at the end of the race. 

The question is of course one of degree.  People chase weight to pretty crazy degrees.  On this boat I used to sail on, we had a saying - "grains of sand."  What this meant was that if you added up enough tiny little grains of sand, you'd eventually wind up with the Sahara desert, so we were always looking for the small gains.  No one carried any superfluous stuff when we raced.  But I recently read a comment somewhere that called 10 grams of difference between two sets of wheels a notable difference.  In my mind, I struggle to call a .7% difference in weight between two sets of wheels notable.  Wheels aren't grains of sand - they're often or even usually the heaviest component on the bike.  This apart from the fact that a 10 gram difference is WELL within the weight variance tolerance of any wheels. 

Bikes used in road races aren't allowed to weigh less than 14.8 pounds.  They often do, since when was the last time an official weighed a bike at a race, right?  I know a lot of people get their bikes down to like 13 pounds, and there are multiple websites devoted to the practice of getting your bike down to the lowest weight possible. 

Weight is something that we always look at every time we evaluate something, and we recently chose not to go ahead with some new rims because we thought their weight penalty outweighed the benefits they brought.  Soon enough I am sure that we'll have the need to evaluate weight versus other factors in other products, and despite weight's objective measurement, we will have to evaluate it subjectively in the mix of other factors. 


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  • jojo thedogfaceboy on

    I think weight matters. A lot. But it is the weight of the cyclist that matters the most. The formula for performance is maximum watts divided by weight in kilograms. If you can throw 7.0 watts/kilogram, you win the Tour. If God gave you 6.2 watts per kilogram, you get to be a professional, living on ramon noodles at the poverty level. Most amateur cyclists should spend more time weighing themselves and less time weighing their bikes. How many times have you met a fat guy who's all gunned up over how light his new bike is? If his ass is sporting an extra 20 pounds of blubber, it doesn't matter that his bike lost half a pound. He's still lugging an extra 20 pounds of lard around with him. After the cyclist has reached a weight where he is less than 5% body fat, then the weight of the bike starts to matter, first on climbs, then on the flats. In my opinion, it's more important that things that move on the bike are light, like wheels, before replacing things that don't move, like frames. Keep in mind, the guy who wins the Tour on a Trek, or a Cervelo, or a Scott could have won the Tour on a November bike. The 7 watts per kilogram is the most important thing. The bike just has to be in the range of acceptable and not break. The most important thing any cyclist can do to improve performance is buy a power measuring device, then hire a coach. With all due respect to Eddy's advice of "ride lots" the coach can help you make the most of your performance by prescribing workouts that create the greatest improvement. To go back to your sailing analogy, the sailor is more important than the boat. If some guy who can't put the boat on the starting line purchases a $300 carbon fiber tiller, guess what, he still can't put the boat on the line. In most regattas, the best sailor wins the race, not the guy with the most expensive equipment. That could change if the weight minimum for bikes were eliminated and the definition of a bike was wide open. Then the Tour would be the America's cup and you'd see guys riding bikes with fairings at 60 miles per hour. Right now, the Tour is still more of a One Design event. The bikes all look different, but the performance is pretty close to identical. Sure, Lance talked a lot of trash about his perfectly developed technology. Which gave him confidence. But the 500 watts he could lay down for an hour gave him the wins.

  • Mike on

    Wow…what little respect I have for golfing as a "sport" just went down a little after reading that article. I do respect the skill behind a good golf game though.

  • Doug P on

    I think to state to many consumers they need to lose weight misses the point. They want a light bike to accentuate their disposable income, and to highlight their attainments on climbing the socioeconomic ladder, not climbing any hill, or even riding the bike at all! I know this is heresy to those of us truly dedicated to cycling, but these consumers pump millions of dollars into the bike industry. As the West moves towards a increasingly stratified class system, this behavior will become more rather than less prevalent. Thank goodness there are retailers like November Bicycles, willing to sell to the rapidly declining middle class. Keep up the good work, fellas!

  • Dave Kirkpatrick on

    K – I think you're onto something with the sensations bit. I agree with you on the first part of your comment but there definitely is a feeling of crispness that comes from stuff without extraneous weight. Or by contrast there might be a palpable feeling of bloat to stuff that's not as lean as it could be. There's a line there between rims whose sidewalls crush if you hit them with your thumb while pumping up a tire and stuff that feels soggy. And I'm not sure that it isn't more the sensation that matters more than the weight. I know, for example, that I CAN NOT STAND to ride wheels with heavy, straight gauge, or insufficiently tensioned spokes. It's like nails on a blackboard to me – the sound, the feel, the bike handles funny, I hate it. I rolled my wife's team mates bike from the tent to the car at a race and could tell within 10' of walking the bike that I couldn't stand her wheels, but they weren't even 100 grams heavier than mine. It wasn't the weight, but they felt dead. Dead.



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