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Discussion Starter · #1 ·
First off, point me to the the thread if this has been beat to death already.
My Q is how much, say as a percentage, performance improvement comes as the bike weight goes from sub 20 lbs to sub 16 lbs.
My feeling is my own variation in weight, fitness, feeding, attitude, technique etc. will mask any performance improvement either climbing or on the flats.
Is this also others experience? Can you get 5% improvement, say averaging 20 mph and not 19 mph on a flat ride, by bike alone?
I guess I am looking for justification of new bike ( I like my current sub 20 steel just fine) Or what components would improve things (prolly the wheels).
I must say I notice the difference between aero low spoke count wheels and regular ones ( the former spin up better). So what else helps if I don't think I am powerful enough to really flex the frame while pedaling.

Thanks
 

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Roadie with unshaven legs
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How much do you weigh? Where do you ride?

Let's say that you are like me, 140 lbs dry. You plus the bike weigh 165 lbs with the heavier bike and 161 lbs with the lighter one, adding 5 lbs for helmet, glasses, jersey, shorts, shoes, socks, and gloves. The total package is lighter by, what, 2.4%? On flat roads, would you even notice it? Nope. On hills, you might notice a little more fatigue at the top of a long climb but I would guess that differences in how you feel from day to day would influence how you feel at the top of a long climb more than the 4 lb difference in bike weight. This is assuming, of course, that you are riding bikes with similar wheel weights. Lighter wheels would accelerate faster and make the bike feel sportier but would it be faster at the end of a long ride? Probably not.

My personal experience is that I don't notice a 5 lb difference in bike weight whether I'm riding on the flats or on the hills.
 

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My guess would be the benefit would be noticeable over very long rides, or races where you are pushing as hard as you can. I however, am inexperienced in this, so it's just an educated guess.
 

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I think there's probably a decent weight area that's acceptable I don't think that it's really conclusive that the uber light bikes feel that much different due to weight, but I do know that lighter generally means higher performance, which usually implies better bearings, better machining, and so forth... so crossing a certain weight threshold probably implies among other things that you're also riding on better hubs, your bottom bracket spins a little more smoothly, your pedals spin smoothly... and all of this will remove some of the effort, too.
 

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If my bike weighed nothing, I still couldn't climb.

Easiest way to get a rough estimate is with percentages. If you weigh 120 and you lighten your bike from 18 pounds to 17, it might be perceptible. My 64cm Atlantis and I together weigh about 270 (never weighed the bike; I'm guessing), so a pound here and there isn't going to make much difference.
Three years ago, though, I lost 30 pounds, and on the same bike, I was a full chainring (not just a cog) higher on most of the hills I ride regularly.
 

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For recreational riders I don't think you will be a better rider by riding a lighter bike. A carbon bike might be better for long hauls like TDF when every pound counts. A carbon bike (per speculation only) will feel faster when accelerating or climbing. So you might put more time on a carbon bike, and push up the mileage, which might pull off some body weight, which will make you faster...but by just riding a bike because it is lighter won't make you a better or faster rider..
 

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Actual numbers

ipiston said:
First off, point me to the the thread if this has been beat to death already.
My Q is how much, say as a percentage, performance improvement comes as the bike weight goes from sub 20 lbs to sub 16 lbs.
On a 6% grade, a 150 lb rider putting out 200 watts would be 0.34 mph slower if the bike weighed 4 lb more. That's about a 3% speed delta. On the flats, the same rider at the same watts would be 0.074 mph slower on the 20 lb. bike.
 

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Kerry Irons said:
On a 6% grade, a 150 lb rider putting out 200 watts would be 0.34 mph slower if the bike weighed 4 lb more. That's about a 3% speed delta. On the flats, the same rider at the same watts would be 0.074 mph slower on the 20 lb. bike.
A wise person I knew said "The only time the weight of your bike really matters is when going up the stairs."
 

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ipiston said:
First off, point me to the the thread if this has been beat to death already.
My Q is how much, say as a percentage, performance improvement comes as the bike weight goes from sub 20 lbs to sub 16 lbs.
My feeling is my own variation in weight, fitness, feeding, attitude, technique etc. will mask any performance improvement either climbing or on the flats.
Is this also others experience? Can you get 5% improvement, say averaging 20 mph and not 19 mph on a flat ride, by bike alone?
I guess I am looking for justification of new bike ( I like my current sub 20 steel just fine) Or what components would improve things (prolly the wheels).
I must say I notice the difference between aero low spoke count wheels and regular ones ( the former spin up better). So what else helps if I don't think I am powerful enough to really flex the frame while pedaling.

Thanks

Here's an online analyser that will show you the actual changes in speed as you reduce weight. Includes other neat factors like slope, altitude, wind speed etc... fun to play around w/ and should give you a fair indication what helps most. Reducing your drag is going to help way more than reducing weight. You can quickly boost your speed from 19 to 20 mph on flat terrain just by riding on the drops or tucking in your profile. Of course for most people easier said than done.

http://www.kreuzotter.de/english/espeed.htm
 

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Just buy whatever looks nice, aesthetics will likely give you the biggest performance improvement (placebo induced) by quite a factor. The only thing i notice between my assumed lighter carbon frame and aluminium boat anchor rain bike when climbing is that the rain bike's stem is dirty
 

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That sounds good on paper..

Kerry Irons said:
On a 6% grade, a 150 lb rider putting out 200 watts would be 0.34 mph slower if the bike weighed 4 lb more. That's about a 3% speed delta. On the flats, the same rider at the same watts would be 0.074 mph slower on the 20 lb. bike.

I have faster times on my steel Colnago then my sub 17 pound carbon bike. The Colnago descends better. Of course I'm a 65 year old over-the-hill guy and the only thing that would make me faster (beside losing some more body weight) is a motor...

What that equation does not take in is heart, and I don't mean heart rate..
 

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One thing that matters to me is the "feeling" of a light bike.

On Sunday I ride my steel Schwinn Paramount which is a good 4 pounds heavier than my other bike. When I start uphill it simply feels heavier and slower than the other bike.

On the light bike, my enthusiasm lets me push harder as I feel myself going (or at least accelerating) a little faster.

I've plugged in all the formulas and data and understand the science.

I still think a light bike "encourages" me to ride harder. But that may just be me. :)
 

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MerlinAma said:
I still think a light bike "encourages" me to ride harder. But that may just be me. :)
look at your whole picture. i ride 2-3 hours a day and own a $4k orbea. i couldn't see a $15k pinarello, unless i spent six hours in the saddle a day.

my factors are: my weight, bike handling, how long on a ride, and how much the bike inspires me to ride.

1) i weigh 150 lbs. a 15lbs bike for me is ALOT easier than a 18lbs bike.

2) a light bike handles better. it helps cornering, accelerating and descending.
geometry helps those even more. a heavy bike makes me focus on it, not the
road, the pack, or my cadence.

3) in the first hour, pricey bikes feel similar. after the first hour of a ride, i notice the bike alot more. it's either a brick on my back, or a tool helping me on.

4) if the bike handles well, it pushes me to ride further and harder. it uses my energy better. it flows through tough rides rather than forcing it. this all comes from geometry.
a heavy, poorly performing bike makes it very hard to ride alot.

PS - don't forget nice shorts, shoes and gloves, jersey and helmet are also good pay-offs. i'm sure that reward levels off somewhere, given the hours ridden.
 

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Discussion Starter · #18 ·
I ride an older $2K, handles nice and is comfy. Most of the other perceived things, feeling fast, vary because of me. As for the first hour, I am just warmed up so the 2nd hour is always better.
I suppose I should try a $4K bike ( or maybe not I might like it).
 

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ipiston said:
Is this also others experience? Can you get 5% improvement, say averaging 20 mph and not 19 mph on a flat ride, by bike alone?
you can get a 5% improvement by changing the type of bike (road bike vs. time-trial bike) but not the within the same bike (Litespeed vs. Colnago).

If you can get 5% improvement by changing bike, I'll be all over it. I have spent $2K to upgrade my wheels so I can shave off 0.5% off my climbing time.
 
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