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Discussion Starter · #1 · (Edited)
When we equate a light bike with going fast, are we are just responding to quality of equipment (and especially quality of the wheel/tire combination)...????? Or are we that sensitive to efficiency gains that we can tell the difference between a decent mid-grade bike and the superbike of our dreams. Or are we all drinking the koolaid?

A thread in the Lounge made me wonder yet again why we all obsess about bike weight--and insofar as it has been studied, the real issue is the output in watts by the rider as compared with the total weight--bike plus rider. So a good dump or one less water bottle separates a superbike from a mid tier bike on that measure.

And clearly the converse of the equation suggests that reducing rider weight and increasing output in watts/lb--both a natural result of lots of training--is the way to get the most gain.

OTOH, revolving mass of wheels, and the kinetic energy required to spin up a light set of wheel is easily felt--and usually the first advice given to an aspiring racer is to upgrade to a better set of wheels. Even so, the efficiency benefits are transitory, and felt most when we are undergoing a series of rapid speed changes, as in criterium racing because once the wheels are up to speed, the savings are a wash and we are back to watts versus weight. We may find a bike 'lively' or 'responsive' in part because of lighter wheels, but it likely is not a big contributor to efficiency at least as currently calculated. {second thought--all of those minute gains may add up to enough energy conserved over the course of a race that we have something still in the tank at the finish--a point not often made by the engineers...]

Drivetrain efficiency--as long as it is decent and doesn't break--the benefits are small at least as they have been able to measure them. Racing--we all know that races can be won or lost on a bad shift (Are you listening Andy?), but aside from that good is good enough, since most of us will never stress our drive train like pros. And yet--need I say it--people spend lots of cash on ceramic bearings.:confused:

Aerodynamics--well this opens perhaps the biggest can of worms of all. Yes, I know that they have done computer modelling and all--but the modelling contains some heroic assumptions. And a lot of the gains AFAIK is to do with testing and setting the rider position, helmet etc to reduce frontal mass. That plus the internalized discipline of maintaining a consistent position and a consistent and planned cadence (often impossible over a long ride or race) pay off more than "bladed" spokes or hidden cables--cool though they be.

And yet--like the chap that posted this morning in the Lounge--we are all believers in the notion that some special combination of stuff will magically make us faster, even if we are 250lbs and have a large frontal mass, or are approaching a good weight for our height but will never produce the 400 watts that an undoped pro will produce.

As our much disgraced LA used to say--it's not about the bike--and as we all echo--it is about the 'motor'.

Ride more if you want to be fitter.

Ride the bike you have and be satisfied.

Ride for pleasure and for fun.

If you are starting out, don't think you have to drop a bundle to enjoy cycling--go to your local thrift store and pick up any decent bike and get outside, put some miles in.

/rant

The Wiki article on bike efficiency is interesting although not complete
 

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Discussion Starter · #4 ·
so, everyone just gets an ugly, boring, heavy utilitarian bike and lives happily ever after...

pretty much zero appeal to that plan.
Sorry if it sounds like that's where I got to--

I only meant to say that people should buy what they like, but don't think that spending a lot of money will make them faster, or don't think you have to spend a lot of money on your first bike to get started.

There are a lot of other considerations--not least aesthetic--why expensive bikes are appealing, and I have as much love for the well-engineered and beautifully constructed frame or components as anyone and all of those weigh in our decisions about what to buy a what to ride.

If people were honest--I liked the recent post in the Lounge about being honest about what kind of rider and what kind of performance they were going to achieve--and then said, 'Screw it--I want to buy that latest zoot bike because it makes me happy, and I don't give a hoot about how little difference it will make in my riding performance' I would applaud them for honesty and wish them the best.

What I think I am reacting to is that people are often starting from that point and then throw out all the other BS about how much faster, how much more aerodynamic, how much faster it will make them climb etc.
 

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Discussion Starter · #5 ·
Some feedback...I stopped reading your post in the second paragraph at this oft used intellectually dull line.

Yes, you lost me at poop ;)
Yes--a cheap shot as it were--

The reason why it is so often used though, is that it does make the point graphically that a couple of pounds more or less is not going to make a lot of difference in your performance.
 

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the topic of 'need vs want' has been pretty well explored.

frugal, practical types go with 'need'...the rest of us want what we want.

I reserve 'practical' for things like clothes and furniture, not purchases related to my hobbies.

ymmv.
 

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They make a difference for pro riders, when seconds count and you are riding fast, the air resistance becomes a major deal, so aero and light can mean the difference between first and fifth.

For the rest of us, I think there is a placebo effect going on. When you pick-up a 17 pound bike it just feels fast, and I think that makes you work harder, and bingo, you're faster. My heavy cross commuter with fenders and bag, etc., just doesn't feel like a race bike, but if I ride it as hard as I can, I doubt the speed difference is all that noticeable from a race bike.

I just have my commuter and a MTB, no race bike, no need for one.
 

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For the most part I think we are into drinking koolaid...

When you are used to riding an entry level bike with entry level components and move directly to a "top shelf" frame and top component group it's easy to feel that there is a difference. What is really difficult to put your finger on is defining what that difference actually is. The light top shelf bike may accelerate a bit quicker and a bit more nimble/twitchy (which get's tagged as light) but sustainable speed is what is really important to me and I think if most are honest they would have to agree. If the two bikes have the same tires and the rider is fit identically the difference in sustainable speed will be so small it will effectively be zero. Increasing speed is all about increasing power which IME comes down to everything but the bike: time on the bike (training), nutrition, recovery, and fit.

All the extras like aero frames, wheels, light frames and components and specialty components are small in comparison but guys like me that know better still buy the stuff. Why? It's hard to say but, it's a loose mix of feel, looks, and performance (shifting differences between SRAM/Shimano and tires for example).
 

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Remember, though, that seemingly small differences are not necessarily mutually exclusive -- you can ride a light bike AND take a large dump before your ride, making your combined weight even less. Lighter bikes and components may not be worth a new purchase, but if you're looking to buy anyway...

Another factor that gets a lot of attention these days is frame stiffness, with the (false) assumption being that a stiff frame will somehow be more efficient or faster. Along with weight this is good example of the prevalence of marketing speek: while I know aero is important, I won't take a prospective purchase to a wind tunnel to test it; but I can be impressed with a bike's weight just lifting it on the sales floor, I can be won over to a frame's stiffness just standing to sprint in a parking lot test drive. Weight and stiffness are nowhere near as important as aero, but they're much easier to demonstrate to potential buyers.
 

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I weigh in at 260 lbs, huge thighs, can sweat off 5 lbs on a long ride. I am a natural born sprinter (on a bike, I mean), as a kid my first day BMX racing I was moved into a higher class my first day out, because I was placing first and 2nd in every heat, you get the picture. I have ZERO finesse, its all power.

Over the years I have gravitated toward heavier/stronger bikes, because I feel safer on them. Light bikes always feel like they are going to buckle when I give them some welly, and I dont trust them downhill. (All in my head ?) I will never be a climber, so the weight doesnt matter to me. At present I go out on group rides with an old kona jake with a nice set of wheels on it, and 32 touring tires. I get some funny looks, but I can keep up. For me, I got older, realised that I am not Eddy Merckx, so I ride what I feel safe on. If i weighed 150 lbs, I for sure would ride an Il Velocerino Custom Carbon Super X Force FeatherMAX.
 

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Discussion Starter · #14 · (Edited)
My imaginary friend Creaky posted this response to the same thread in the Lounge that got me started:

Here's what really matters in a mass-start racing bike:
- does it fit you correctly
- is it mechanically sound and reliable
- does it weigh less than ~25 pounds

Everything else is fashion, advertising and cosmetics.
And I think you could apply a similar cut-off for the various types of bikes we ride (although I would want to go a little lighter than Creaky if I were still racing).

And really, cycling for me is a big tent--as long as people are getting out on something that rolls, I'm happy for them.

So it is less the choice than the cant that often surrounds the choice.

(BTW, I'm feeling less dyspeptic than this morning since I went for a ride!)

My thought while riding that boomers like me are probably to blame. As David Brooks argued in Bobos in Paradise--we the boomers wanted to retain our anti-crass materialistic cred and so we felt we could spend $500 on some ultracool anorak since we could justify it in terms of high quality, exquisite fabrication etc--even if we only wore it to take out the garbage, and at the same time reject a lot of the objects of conspicuous consumption that our parents' generation embraced.
 

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Discussion Starter · #15 · (Edited)
They make a difference for pro riders, when seconds count and you are riding fast, the air resistance becomes a major deal, so aero and light can mean the difference between first and fifth.
I'm inclined to think that a lot of little things add up for pros--the lightness of the bike and the wheels, the infinitely careful setup by the mechanics of bearings and such, the aero advantage (although I think this is small for a conventional bike)--and as I have suggested, the energy conserved for the finish may be the most important benefit.

My oft-told story about this is my first experience on a long tour--riding with my brother and a friend who both had nice bikes and I was riding a clunker. While I could keep up, by the end of a long day--8 hrs plus of riding-- I would be shattered, and they would be fine--and we all had about the same level of fitness. And this was consistent over 10 days of touring, so clearly there was some cumulative benefit being reaped by the lighter bike and better equipment, even if it is hard for the engineers to measure its magnitude.

For the rest of us, I think there is a placebo effect going on. When you pick-up a 17 pound bike it just feels fast, and I think that makes you work harder, and bingo, you're faster.
And perception might be reality in this case.

When you are used to riding an entry level bike with entry level components and move directly to a "top shelf" frame and top component group it's easy to feel that there is a difference. What is really difficult to put your finger on is defining what that difference actually is. The light top shelf bike may accelerate a bit quicker and a bit more nimble/twitchy (which get's tagged as light) but sustainable speed is what is really important to me and I think if most are honest they would have to agree. If the two bikes have the same tires and the rider is fit identically the difference in sustainable speed will be so small it will effectively be zero. Increasing speed is all about increasing power which IME comes down to everything but the bike: time on the bike (training), nutrition, recovery, and fit.

All the extras like aero frames, wheels, light frames and components and specialty components are small in comparison but guys like me that know better still buy the stuff. Why? It's hard to say but, it's a loose mix of feel, looks, and performance (shifting differences between SRAM/Shimano and tires for example).
And guys like me buy it for the same reasons--so maybe I'm just talking to myself and clarifying why I still care.

I mean whether I put Veloce or Record on the next build will make zero difference in my performance, add only marginally to my enjoyment of the bike, and yet, when I'm shopping I'm lusting after those Record cranks....
 

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I don't about any science or theory, but I do know I have 2 CF bikes both equipped with ultegra components and similar wheelsets. One is about 2lbs lighter because of lighter frame, CF steerer, seatpost, and lighter handlebars. I can definitely climb better with the one that is 2lbs lighter and it is very noticeable to me.
 

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Discussion Starter · #17 ·
Remember, though, that seemingly small differences are not necessarily mutually exclusive -- you can ride a light bike AND take a large dump before your ride, making your combined weight even less. Lighter bikes and components may not be worth a new purchase, but if you're looking to buy anyway...

Another factor that gets a lot of attention these days is frame stiffness, with the (false) assumption being that a stiff frame will somehow be more efficient or faster. Along with weight this is good example of the prevalence of marketing speek: while I know aero is important, I won't take a prospective purchase to a wind tunnel to test it; but I can be impressed with a bike's weight just lifting it on the sales floor, I can be won over to a frame's stiffness just standing to sprint in a parking lot test drive. Weight and stiffness are nowhere near as important as aero, but they're much easier to demonstrate to potential buyers.
Totally agree about "stiffness" as the ultimate triumph of marketing over common sense--you want a bike that doesn't turn into a noodle under you when you hammer, and there is an argument to be made that as we as a population have gotten heavier on average bikes from back in the day are not stiff enough if you are 200lbs--the marketers have taken that an run all the way to the bank.

I put together a bike last year--a Concorde El-OS (either Billato or Ciocc made depending on how you think the subcontracting was arranged)--and I can flex the chainstays under hard acceleration (and like most of us, I am heavier than when I raced (~185 vs 150)--and yes it was noticeable. What I loved though was how direct the contact with the road was--I swear you could feel the shape of a pebble you rode over (or tell if a penny on the road was heads or tails up) and how forgiving the ride was--qualities often sadly missing in today's over-stiff CF frames.
 

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I think the simplest remedy for expensive aero equipment is for the UCI to stop being retarded and to allow wind screens that redirect air around the rider's torso. There goes half of your drag right there.
 

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Discussion Starter · #19 ·
I don't about any science or theory, but I do know I have 2 CF bikes both equipped with ultegra components and similar wheelsets. One is about 2lbs lighter because of lighter frame, CF steerer, seatpost, and lighter handlebars. I can definitely climb better with the one that is 2lbs lighter and it is very noticeable to me.
You know--you are probably right--and yet the engineers will tell you that it is only because the total package is 2 lbs lighter, and it is indifferent whether that has been shed from the frame or from somewhere else.

When I read the arguments on efficiency--that it was watts output vs total weight going down the road--I balked as well, since that did not jibe with how I have felt different bikes over the years, and why my first true racing bike was a complete revelation.

Maybe the science will catch up?
 

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Discussion Starter · #20 ·
I weigh in at 260 lbs, huge thighs, can sweat off 5 lbs on a long ride. I am a natural born sprinter (on a bike, I mean), as a kid my first day BMX racing I was moved into a higher class my first day out, because I was placing first and 2nd in every heat, you get the picture. I have ZERO finesse, its all power.

Over the years I have gravitated toward heavier/stronger bikes, because I feel safer on them. Light bikes always feel like they are going to buckle when I give them some welly, and I dont trust them downhill. (All in my head ?) I will never be a climber, so the weight doesnt matter to me. At present I go out on group rides with an old kona jake with a nice set of wheels on it, and 32 touring tires. I get some funny looks, but I can keep up. For me, I got older, realised that I am not Eddy Merckx, so I ride what I feel safe on. If i weighed 150 lbs, I for sure would ride an Il Velocerino Custom Carbon Super X Force FeatherMAX.
You've made the right choice--the first concern ought to be how the bike feels to you. And you are not alone. I think I remember Tom Boonen as having chosen some pretty stout bikes over the years for similar reasons
 
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