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Bike Frame weight and Climbing(28 posts)

Bike Frame weight and ClimbingSimpleGreen
Apr 27, 2001 7:52 PM
Here are two questions
Take a 22-pound old-fashioned steel road bike, a 20-pound EL-OS (or equivalent) steel road bike, and a 17-pound AL/Carbon/Ti bike with nice wheels. How much faster could one hammer up a 5 - 10 mile climb? Assume the rider is say 150 pounds and in good shape.

Now suppose the bikes have the same tricked-out components except for frame and fork. A Steel frame/fork combo would be about 2 pounds heavier. How much faster would the rider be on an AL bike on a hill climb?

How much performance can one really buy?

SimpleGreen

PS I just thought of another Mastercard Commercial: Colnago C-40 - $3800, Campy Record build kit - $1700, Campy wheel upgrade - $300, (Then a pro whizzes by the purchaser) 400 watts of power at lactate threshold - Priceless!!
re: Bike Frame weight and Climbingto the summit
Apr 28, 2001 6:41 AM
Has this not been discussed about a million times? Most colleges offer physiology 101 but it has so much more to do with the mental aspect, fit of the bike, weather, your competitive urge at that moment, did you just have a baby?, did you just have 3 beers?, did you just load up on EPO, etc., etc., etc. I realize you probably mean if all things being equal...but they never are in the real world. See your comment on the pro whizzing by with 400 watts of power? Let me ask, would Lance have NOT have won the last two years had he been on his old Eddy? It's ridiculous to think 'not'.
duuude!SimpleGreem
Apr 28, 2001 7:25 AM
Thanks MR. Sarcasm!

Of course this is an IDEALIZED question. Don't people ask questions that are IDEALIZED to realize if upgrades are worth it?

Yes, I too believe the rider is the most important factor. THis is WHY I'm asking how much of a difference does a bike truly make. You aren't seeing my point in the first post. If bikes don't make a significant impact even on climbs, then why should most people consider buying expensive, ultra-thin tubed AL frames that will last only 10,000 miles? I'm not trying to tell people how to spend their money either, but shouldn't the hype over frame weight get toned down? Aren't bikes being sold almost solely on weight issues?

Weight does make a difference, but not enough, in my opinion, to the average amateur cyclist.

Yo! Enjoy the roads!!
re: Bike Frame weight and ClimbingBart S.
Apr 28, 2001 7:34 AM
People buy things for many reasons - budget, ego, etc., but most purchases are emotional. After all, does a $75,000 BMW provide three times the features and performance of a $25,000 Honda Accord? No, but people buy them for status.

Just buy what you like and enjoy the road. A few pounds more or less is not that important.
re: Bike Frame weight and ClimbingJofa
Apr 28, 2001 8:06 AM
(There are an awful lot of hackles being raised by what is surely a simple question!)

You should be able to work out all that stuff here:

http://www.analyticcycling.com/ForcesLessWeight_Page.html
ThanksSimpleGreen
Apr 28, 2001 8:10 AM
Just the info I was looking for.

Enjoy your Ride!

SG
You can also calculate how much better3kidney
Apr 28, 2001 1:28 PM
you would do losing 9kg of excess body weight going up an 8.5% 13km climb (and see why Lance is kicking ass on Hautacam every year in the Tour).
re: Bike Frame weight and Climbingsteveuk
Apr 28, 2001 3:57 PM
I'm sorry if u believe this total load of nonsense - (http://www.analyticcycling.com/ForcesLessWeight_Page.html) - you must be very unquestioning! Let's assume the 5kg lighter rider has lost this weight from his #body fat#.

Well, using an equation based around those forces only TOTALLY ignores the physiological benifits of a body carrying less fat for a start. Also, someone carrying 5kg less weight will have a not insignificant increase in #power output# while burning the #same energy#! So the equation is fatally flawed on two levels - obviously!

A thiner body has less drag! Obviously!

A body carrying less fat will not overheat as quickly as a fatter more insulated body and performance will be increased on a hot day - one of the physiological benifits.

A thinner body I'd say needs less water to keep hydrated (fat also need to be hydrated!) and so the lighter rider can carry less water and be even lighter on a long ride. Fat also need oxygenated! So less oxygen may be going to muscles when they are surrounded by fat!

Weight off the bike is NOT the same as weight off a rider because a bike doesn't have increased power output at the same calorie burn rate when lighter - a rider gains performance when #less fat is being maintained#.

So the equation in question may be applied ONLY to weight off the riders bike and even then it doesn't take into account the resulting increase in power output at identical calorie consumption!! Don't believe stuff based on presentation people - use yer minds as well as those legs. Ofcourse if I'm wrong please shoot me down.
mathematical nonsensesteveuk
Apr 28, 2001 3:58 PM
I'm sorry if u believe this total load of nonsense - (http://www.analyticcycling.com/ForcesLessWeight_Page.html) - you must be very unquestioning! Let's assume the 5kg lighter rider has lost this weight from his #body fat#.

Well, using an equation based around those forces only TOTALLY ignores the physiological benifits of a body carrying less fat for a start. Also, someone carrying 5kg less weight will have a not insignificant increase in #power output# while burning the #same energy#! So the equation is fatally flawed on two levels - obviously!

A thiner body has less drag! Obviously!

A body carrying less fat will not overheat as quickly as a fatter more insulated body and performance will be increased on a hot day - one of the physiological benifits.

A thinner body I'd say needs less water to keep hydrated (fat also need to be hydrated!) and so the lighter rider can carry less water and be even lighter on a long ride. Fat also need oxygenated! So less oxygen may be going to muscles when they are surrounded by fat!

Weight off the bike is NOT the same as weight off a rider because a bike doesn't have increased power output at the same calorie burn rate when lighter - a rider gains performance when #less fat is being maintained#.

So the equation in question may be applied ONLY to weight off the riders bike and even then it doesn't take into account the resulting increase in power output at identical calorie consumption!! Don't believe stuff based on presentation people - use yer minds as well as those legs. Ofcourse if I'm wrong please shoot me down.
then what?DaveG
Apr 28, 2001 10:33 AM

I see someone already posted the analytical cycling web link. From a pure physics view that should tell you how much time you will save with the weight savings. If you are already at the highest level of racing fitness, then you may very well need the very lightest to avoid losing anything the the competition. If you are a recreational rider or not-so-competitive racer, then after you have bought that small performance margin, then what will you do? I don't know anyone who went from off-the-back to #1 merely by spending money. Thats not to say some performance can't be bought (especially when it come to aerodynamics) but the point is it's all bought - its not you.
Hell yes you can buy performance!!!Thiderek
Apr 28, 2001 11:26 AM
Give the guy a break.

I just switched from an Aegis(2000) Carbon with 94 Campy Chorus to a 2001 De Rosa with Campy Record 10 speed. I am an absolute horror on my new bike. I ruin my buddies on the hills now. I attribute it all to the weight difference. I shaved close to 3-4 pounds by switching to the bike. Plus the new groupo really does the trick. I was coddling the old groupset after all the years of abuse. Now I have a smoothly shifting bike that handles like a charm. I am trying to figure out what to do with the Aegis now. The purchase was a huge investment but it was worth it. Talk physics all you want. I have the answer from pure sweat and trial.
It's mostly your imagination....engineer dave
Apr 28, 2001 2:27 PM
The new groupo can't hurt, but the idea that saving 3 or 4 pounds will make a huge difference in performance is strictly imagination. A 3 pound reduction for a combined rider and bike weight of 180 is only 1.6%. If you've been averaging 20mph, now might average 20.3mph, if all your riding was up hill. The weight reduction has no effect on the flats and will reduce speed on down hill runs.

Dropping 10 pounds from the gut is a lot more valuable.
Methinks you are wrong.Thioderek
Apr 28, 2001 2:51 PM
The thing you are manipulating while riding is the bike. If it weighs 15% less than your old one, you are going to notice a big difference. People fight for small pecentages in this sport-15% is huge.

Your body responds differently to the new, lighter, and easier to manipulate bike. Your body is static in the whole equation; unless you are steadily losing weight. If it takes less energy to move the bike, you have a difference. Especially since you are still as strong as you were when your bike weighed more. Hence you move faster and easier with a smaller expenditure of energy to complete the same tasks.

I went from 3 laps in Central Park at (19.5 miles=3 laps) at 20 minutes a lap, to sub 17 minute laps for three (51 minutes) with my new bike. The bike is easier to muscle up a hill, to roll on a flat or barrel down a downhill. You are right in that there might be a mental element to all this, but the stopwatch doesnt lie.

Your estimate of 20mph to 20.3mph is sorely miscalculated because the bike isnt the object that weighs 180 pounds. My heartrate is also lower due to the ease of the climbs with the new bike.

I do agree that losing 10 pounds in gut would help greatly, but then you are looking at a smaller % difference than the difference in the weight of the new and old bike.
Methinks you are wrong.steveuk
Apr 28, 2001 3:21 PM
Central Park is flat though??? Looks like you just got a better rolling bike - less rolling resistance or pedalling resistance - better tyres? better gears?? worn chains/gears reduce power transfere - your old bike must have been in a bad way maybe.
Methinks you are wrong.Thioderek
Apr 28, 2001 3:25 PM
Do you live in New York City? Tell that to the marathon runners every year.

It is far from flat.
Methinks you are wrong.steveuk
Apr 28, 2001 5:01 PM
nah man I've only seen it on the TV! But it's far from Alpine?
take a physics course, stupid (nm)dave
Apr 29, 2001 5:15 AM
.
Come say that to my face. Oh you wouldn't?? nmsteveuk
Apr 29, 2001 5:13 PM
nm
Dream On - Live Weight vs. Dead Weightgrz mnky
Apr 30, 2001 10:15 AM
The difference between live and dead weight can not be ignored. From a total system perspective 3 lbs. is 3 lbs. and F=ma still rules the day. However, by taking the weight of the bike and keeping the body the same there is the same amount of power from the rider available to haul himself and a lighter bike up the hill. Reversing the situation the rider weighs less so there is less power available assuming strength is the same and gravity is sole soource of force. things can be complicated a bit by having the rider using muscle to pull up against the bars, but the 3 lbs. missing in terms of body mass doesn't change. Hope this perspective helps.
re: Bike Frame weight and Climbingcracked
Apr 28, 2001 4:39 PM
i totally agree with those that make it the physiological difference, not the bike. I never can believe that while racing/training I could be up with the front group if my bike was 1/2 or a pound lighter. It doesn't mean squat. The best thing to do, is pick the right parents. Nuture that gene pool and you'll have world class climbing partners. LeMond/Amrstrong/Pantani...the other great climbers, could y'all's butts on a Huffy. You you want to spent $90 buying ti bolts to save 3 ounces...cool...so do I. But it ain't gonna get you up the hill any faster. Strongest/smartest man/woman wins. Period.
You can maximize your personal performanceDog
Apr 29, 2001 3:57 PM
Yes, there are indeed many things you can buy that will make you faster. However, you will never be able to buy a bike thing that will help you to exceed your personal performance capabilities at the time. Even if I had a bike that weighed Zero, and had Zero rolling resistance, I'd never keep up with Lance for even a mile up a steep hill. He makes twice the power, and the relatively small difference in weight (for the whole body/bike system) cannot possibly make up for the power difference. Now, if I could weigh half of Lance, and make more than half the power, then we're talking. Of course, that ain't happen'en.

Here are the things, in my experience, that you can buy and expect meaningful results:

1. Light (1600 grams per set or less), somewhat aero wheels with good hubs. I can tell the difference. Go even lighter and more aero, and you'll see more results (like with a Lew or Zipp 303). Tires, you have to consider the trade off of light ones getting flats more, and factor that risk in.

2. Aerobars, if you ride solo on relatively flat ground. They make a huge difference, even at 18-20 mph, on flat ground (the longer the ride, the more the difference), compared to riding on the tops or hoods, and about half that difference compared to on the drops. But, most people are not comfortable on the drops for long periods of time like they could be on aerobars.

3. The right gearing. Having gears that allow you to spin where necessary, well spaced, with the right top end for your terrain and power can make a big difference.

4. The right clothing. T-shirts or jackets whipping around in the wind can slow you a whole lot. In fact, I read testing that showed that even an unzipped compared to zipped, well fitting jersey, down a hill, increased drag more than the difference between conventional 32 spoke wheels and the most aero wheels. I zip up every descent (where time counts).

Don't let people tell you that you need to lose fat before thinking of upgrading or lightening your bike. B.S. Both will make you faster. Who the heck passed a law that you can't have a light bike until your body fat is under 8%? OTOH, I wouldn't recommend a 15 pound bike if you are 250 pounds. You also have to think about the structural limitations of the materials.

There are laws of physics that apply and are meaningful. Less mass will get up a hill faster, all else equal. How much faster? Well that may depend upon where it is. If I'm focusing on the bike, I'll start with wheels.

Be realistic in your expectations, though. If you are a Cat 5 getting dropped on every big hill, the bike is not responsible, and even a 14 pound bike likely won't keep you with the group. However, if you have trained for years, are very fit, dropping from a 21 to a 15 pound bike may well mean the difference between winning and 5th place or more.

I've heard it said that "bikes don't set records, people do." You can't exceed your personal performance ability at the time, no matter what the bike. That said, the physics actually make weight dropping more important for lighter riders and/or those with low power. Do the math. Speed up a hill is largely a function of power to weight ratio. The more power the rider has, the less significant the weight is. The less power, the more important the weight reduction is. It's actually the reverse of how many people think, those that argue only the pros need worry about bike weight.

My advice, yes, get your body weight down to a reasonable percentage, even less if you want to compete. For racing, 8% is pretty reasonable. As for the bike, get it as light as you can afford and still keep it reliable and comfortable enough for the events you do.

Doug
The right stuffSimpleGreen
Apr 29, 2001 4:38 PM
Thanks Doug! You give good advice.

I posted my topic initially to see how people would react to this issue. I am of the opinion that too much hype is being made out of component and bike weights. Weight is important, but it seems to be getting out of hand in some ways.

Reading the reviews of various products on this site is also indicative of this. Some reviewers wax poetic about how they are taking big time cuts into their PR's after dropping a couple of pounds off their bike. It's possible, but unlikely. Racers need good enough equipment to keep them in the game. I can understand if a racer, who is at his ideal weight goes and gets a fancy lightweight bike.

Most riders, however, don't need superlight stuff, especially non-racers. Now I don't care if they do have it. I like that stuff too! If someone wants to ride superlight stuff, I support him or her all the way. However, I hope some people realize that their reviews and/or comments of these products can be overzealous and unobjective.

In the end, all that matters is that we enjoy riding. But a little objectivity would be nice. Now if only I can get in more miles...

Happy Riding!!

SG
How can you say that?Thioderek
Apr 29, 2001 5:01 PM
Ok, maybe I was a little over-zealous in stating that you can buy performance, but dont even try to tell me that I didnt take that time off my PR. I have the heart rate info downloaded while on my old bike, and the new info while riding the new one. The time and heart rate is all there in graph format. I fail to see how the timer can lie.

Why is it so hard to believe that I am faster on the newer lighter bike. I have ridden as a messenger for close to 8 years and raced throughout the 90s doing triathlons and some other racing in So Cal. I cant wait to try out the new bike in competition. I know without a doubt that I am significantly faster on this new bike.

As for the rules about waiting until you are under a certain weight to buy a lighter bike. I am not overweight, but had I known this rule existed-I still would have bought the bike. I dont pay attention to rules. No good bike messenger does. I feel good riding the bike and that is all that matters.
I'm not saying thatSimpleGreen
Apr 30, 2001 8:25 AM
I think you're misreading the statement.

I believe that there are differences, but sometimes they are made to hyperbole. Like people taking 1 hour off of a century time, or suddenly being able to crush their buddies on a 4 mile climb. I do think that there are differences, but sometimes they are exagerrated.

Remember, I'm not saying one should NOT buy cool bikes. In fact I am all for them, but I feel that some (but not all) people get a bit emotional about their reviews.

I'm not knocking your ride. I'd be the first person in line to get a C-40, if i could. I'm not telling people to wait until they get skinnier either. It's just that there are better ways to get performance boosts rather than a TI bolt kit for $300 or even a really nice set of wheels. Look, if a person is 20 pounds overweight, what's the first this that person should do IF he wants to be faster.

I agree with you. Ride what you like and makes you feel good. I just hope I prevent someone from buying into too much hype.

SG
re: Bike Frame weight and ClimbingLBS Guy
Apr 29, 2001 5:26 PM
You say that frame weight and overall bike weight dont matter that much, then why do companies like TREK, Cannondale, Specialized, Colnago, Pinarello, etc. have on going research of how to make bikes lighter. If it didn't matter that much then why would the pros be riding 14lbs bikes. but you agrre that maybe pros need that stuff ok. well then how come just about anybody who rides midly seriously have a bike under about 20lbs. because it does matter, if you have ever ridden a century on a 20 lbs bike and then ridden the same century on an 18 or 19 lbs bike you can tell the difference, lighter weight means less fatigue, if you dont have that extra weight to push the you dont have to work as hard to go faster. If you have a 15lbs bike you dont have to do near as much work to push that bike 100 miles then if you have a 20lbs bike. this is straight common sense, if your climbing a 15k hill will a 7% rise on a 15lbs bike you'll use alot less energy than you would with a 20lbs bike or anything heavier, try riding your bike with a rack on the back with a 5lbs dumbell, then go ride the exact same course without that weight trust me you'll tell the difference. no you can't buy the strenght of Lance Armstrong, but if you and your friend are about the same strength and your bike is 1-1/2 lbs lighter you'll be faster than your friend. It's common sense not rocket science.
Later
Remember its not the bikes fault you suck, but if your bike does suck its not helping you any.
re: Bike Frame weight and Climbinggator
Apr 30, 2001 6:32 AM
First off....you may singularily have the worst spelling/grammar/punctuation I have ever seen on the web. I'd be way more concerned about my lack of basic English 101 than any cycling concerns.

Most pros have bikes nowhere near 14lbs. I'd be quite willing to bet most pros hardly know what bikes their riding, period. They get new bikes all the time (certainly year to year and are constantly switching teams). In an average 'tour' they may ride 3,4, or 5 different bikes depending on the course that day. They use their bikes as a means to an end. Bike companies, like any manufactuer, are always striving to make a better mouse trap. Ten/15 years ago, your choice was steel, steel, or steel. Now there is a multitude of frame material options, construction techniques, etc that have made frames lighter, better, and sometimes/hopefully stronger. But it very much gets to a point of diminishing returns. I rode a 12lb, fully raceable bike once and it was plain scary....almost un-rideable it was so flexy. A cross 'breeze' would send me sideways. No thanks. And, I agree with you (I think, I had a hard time reeding yours writing), not it's not rocket science, but there is a hell of alot more involved than a 'light bike'. A light bike, under the wrong rider, is a seriously inefficient machine. It is SO MUCH more the rider than the bike - weather, fatique, and mental outlook play a huge aspect in the sport, much, much, much more so than than a pound of weight on a bike.
Duude#2SimpleGreen
Apr 30, 2001 8:47 AM
I'm only pointing out that frame weight is over-hyped. It does make a difference, but IMHO much less than what people are saying.

Losing even 1KG on your frame won't drastically affect your best century time. If you draft off of a large pack, you can knock 45 minutes off your time. 2.2 pounds less frame weight won't get that done.

Another point--in some of the spring classic races in Europe, Mercury won on steel lemonds. These aren't the lightest or stiffest frames out there. Of course they have tricked out bikes, but the frames are 1 to 1.5 pounds heavier than a Pinarello. So what?

weight matters. But to the average amateur cyclist, it doesn't matter as much as people would like to believe. I like cool bikes as much as the next man, but frame weight is overhyped.

SG
re: Bike Frame weight and Climbingmuncher
Apr 30, 2001 9:49 AM
Not saying you're wrong at all, but the cynic in me says they make 'em lighter so that we'll buy em. A decent frame will last years and years - and you can change the components. It's like golf stuff - you gotta make the market, because the products won't - they last too long. Why do we have 5/6/7/8/9/10 speed in series - as if they couldn't have made 9/10 when they made 7... It lasts too long - who ever wore out there 7 speed 105 completely? On the other hand, who really wants and thinks that they can't be competitive without 10 speed Ultega/D-A? Now we're talking numbers.....

End of rant - thank you for your attention....