What is the truth behind bike weight? Does it really help THAT much? - Page 2

KERBLAM! There ya go...

If you think of the factors that affect drag, and therefore top speed, mass doesn't come into it. Unless you are going up or down a hill of course. Well, there's a miniscule variation in bearing drag and rolling resistance due to weight, but whatever...

Since aerodynamics is the biggest component of drag, I'd say the variation in riding positions between the bikes is what's causing the difference in top speeds.

John Swanson
www.bikephysics.com

Why do you hate Cervelo so much? And why do you hate America?

With due respect... the percentage weight reduction of the stand alone bike is irrelevant. It is the nine pounds difference that is relevant.

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Relevant to what? Speed? Feel? Look?

As I said, using that 36% weight reduction as a parameter is probably a worst case scenario. If the OP can't feel a difference, then he won't feel the difference b/n 25lb to 16lb. If he does, then he can go and test ride a physical 16lb bike. In any case, it's a close to zero cost experiment.

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Morphed Bianchi Camaleonte IV 2006, Ridley Damocles 2006, Garmin, Mac

Saving a good chunk of weight (off bike or rider) can make a noticable difference off climbing performance. I'd like to climb 5% faster.
So the theory that has been driven into cyclists is that even a small difference in weight will make a small difference. You might not notice each small difference but they add up.

And thats where our ego and marketing kicks in. Racing or otherwise we want to be able to keep up or push ahead, and every advantage is desired.
The marketing departments are always telling you people win on thier products, your competitors/mates have this advantage, you need it too.
Plus there is prestige to owning a "quality" bike, jut like owning a "quality" car.

For me personally, I'd looooove a high end bike that weights 7.5kg and looks pretty. But the extra it costs to go from mid range solid dependable and resonable looking to high end flashy light weight does not result in enough performance increase for my type of riding. Beides a $10,000 bike crashes just the same as a $3000 bike, maybe even worse!
For some people what they percieve in gain is worth the extra money TO THEM, so let them spend it. The rest of us get the trickle down effect of the developement that goes into these over priced items.

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Precision Sports

PhillP: I hear you. But it stands in stark contrast to the ceramic bearing you are selling in your signature line.

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Morphed Bianchi Camaleonte IV 2006, Ridley Damocles 2006, Garmin, Mac

Let's see what has been mentioned already bike weight, rider weight, terrain, aerodynamics.
Anyone mention wattage output to weight/drag ratio?

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Schedule your priorities, exercise at least one hour a day or be dead for 24 hours a day.

I think he should find out for himself but there is SO much more involved and different when considering a bike that weighs this or that and also when comparing to his 25 pound Schwinn. Lots more than just weight but that's all bike makers can measure and point to so less weight becomes better when all it really is lighter.

A "bit" unscientific? Totally irrelevant info, I'd say.

Tell you what though, some nice skinny tyres make a whole lot of difference. Coming from my hybrid on 40mm to my roadie on 25mm is like floating down the road.

The main reason low weight is an advantage is that its easier to carry it home when you stick it in a pothole and bend the front wheel (thats my experience anyway )

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Its not what you've got its what you do with it.

Doooohhh!!!

Yeah, but if you had some solid heavy wheels on, maybe you wouldn't have bent it.

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"All that we see and seem is but a dream, within a dream..."

The higher momentum would have collapsed the concrete barrier instead.

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Morphed Bianchi Camaleonte IV 2006, Ridley Damocles 2006, Garmin, Mac

+1 for your statement ".....less weight becomes better when all it really is is lighter". Weight is easy to measure, so it gets measured and compared, while the important (and hard to achieve) parameters of strength and durability tend to be ignored in buy decisions. After all, weight can be shaved off any part of the bike at little or no cost to the manufacturer. Just make the part thinner and bingo, less weight = more sales.

I don't think it is just a matter of making a part thinner. Doing just that will make that part a POS, for which nobody would pay for let alone give a premium for. They have to make it durable in addition to making it light for it to be a good sell. But yes, weight is a good marketing ploy, when for the average Joe, it is going to make an insignificant change to the speed on the bike.