Bicycle Weight for Dummies

Lightweight road bike

In case you haven't noticed, the staff at the Antisocial Network includes a lot of cyclists. As a consequence, we turn up a lot of bogus freelance posts about bikes; most dealing with maintenance and repair, with a few idiots trying to explain gears. We've never run across one, however, on the topic of bicycle weight... until now. Meet eHowian David Dorion, who pretended to know enough about the topic to write "Does a Lighter Bike Really Make a Difference?" in their new SportsRec.com niche by Leaf Group.

According to Dorion,

"The debate rages on. Does a lighter bike make a difference? This question has been and will continue to be the topic of conversation anywhere from Sunday club bicycle rides to all-out racing within the pro peloton."

Ooooh! he said "peloton"! And that's about the only thing he said that makes sense: no experienced cyclist anywhere disagrees that "lighter is better"; ergo, Dorion must not be a cyclist. So why's he writing about this? Because there's no other way to make money with his "writing" degree?

David blathered on for more than 600 words, the vast majority of which were about the additional cost of a lighter bike, the handling of a carbon-frame bike, and how to reduce the weight of your existing bike. That last is actually rather amusing, since he suggests that you reduce the weight of your bike thus:

"Buy your bike a new set of lighter wheels or some lighter components..."

Just out of curiosity, we looked at the cost of a high-end set of wheels and a Shimano Ultegra drivetrain. A Shimano Dura-Ace 9100 wheelset would set you back as much as $1100, while a set of Ultegra shifters adds another $300. That's not to mention derailleurs, cranks, chain rings, and cluster. Yeah, sure: buy "some lighter components"! [Hint: it's usually cheaper to buy them already on the bike.]

In fact, Dorion dodged the question (mostly because he didn't know the answer): Yes, a lighter bike makes a difference. It makes a difference because of physics: Newton's second law says that the force necessary to move an object is equal to its mass multiplied by the rate of acceleration. Now that might seem a little science-y to those with writing degrees like David's, but it's really simple. Let's have a look:

To move a bicycle forward across level ground at a steady speed, you must overcome air resistance plus a little bit of friction. That's the "acceleration" variable. Compare identical riders on two bikes, one weighing 20% more than the other: if air resistance and friction are the same for both riders, then the one difference is mass ("weight"). It should be obvious, then, that the force necessary to keep the heavier bike moving is greater than the force needed to keep the lighter bike moving. It's even more pronounced when you have to climb a hill... But Dorion either lacked the cycling background or lacked the science background to even think of such a difference, instead prattling about how "Some bicycles that are based on their light weight can cost upwards of $10,000."

The real answer (which he never provided) is "Yes." David didn't know enough to say so, and for his ignorance we hereby award him the honor of being our Dumbass of the Day.

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