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-   -   Bike weight impacting speeds (https://www.bikeforums.net/showthread.php?t=1176847)

shelbyfv 10-15-19 02:42 PM


Originally Posted by kevin****t (Post 21000955)
Why I am interested is because I am almost in the range for being a possible "lead pack or break away" finisher

Maybe a quote will alert the OP that we are hoping for an update.:thumb:

vikay 10-22-19 07:44 PM

I owned a Trek Alpha 1.2. I upgraded to an Emonda SL6. Felt no real difference. I did feel good though.
Get pedals/shoes they say. Felt no difference.
Get carbon rims they say. I still feel no difference.

But I do have a 16 lb bike after all of this compared to my 22 lb Alpha.

topflightpro 10-23-19 06:52 AM


Originally Posted by vikay (Post 21175730)
I owned a Trek Alpha 1.2. I upgraded to an Emonda SL6. Felt no real difference. I did feel good though.
Get pedals/shoes they say. Felt no difference.
Get carbon rims they say. I still feel no difference.

But I do have a 16 lb bike after all of this compared to my 22 lb Alpha.

That's your problem. You won't notice the difference until you get under 15lbs.

shelbyfv 12-28-19 09:23 PM

Aero helmet may make the difference! https://www.bikeforums.net/general-c...sell-angi.html :thumb:

ThermionicScott 12-28-19 10:14 PM


Originally Posted by shelbyfv (Post 21261427)
Aero helmet may make the difference! https://www.bikeforums.net/general-c...sell-angi.html :thumb:

I'm going in. :lol:

Doge 12-28-19 10:45 PM


Originally Posted by vikay (Post 21175730)
I owned a Trek Alpha 1.2. I upgraded to an Emonda SL6. Felt no real difference. I did feel good though.
Get pedals/shoes they say. Felt no difference.
Get carbon rims they say. I still feel no difference.

But I do have a 16 lb bike after all of this compared to my 22 lb Alpha.

I feel that same way with a lot of audio equipment. $300->$3,000 - no difference. Then you play with it a bit, talk to others and tune it in and there are differences. Wine too...

But to bikes, the base material is different. Carbon, vs, steel, vs Alloy, vs Ti vs Hybrid. They should feel different to you. If they don't you are very fortunate. Buy the least expensive stuff.

mohamilton 04-22-20 04:01 PM

Weight makes a huge difference! Light bikes are so much more fun to ride, they get to speed faster, climb better, make you want to go faster, bore your girlfriend, what's not to love?!

xroadcharlie 04-23-20 12:09 PM

Using "bikecalculator.com" the difference between 185 lbs and 175 lbs is .07 mph with 200w power. Despite our perception. The heavier bike will take about 5% more power to accelerate and climb, But that power is returned when we stop pedaling, it's only lost when braking . More rotational weight exasperates the effect slightly, But again the extra energy is not lost. FAR more important then weight is wind resistance, rolling resistance, the engine and strategy.

bbbean 04-23-20 01:46 PM


Originally Posted by kevin****t (Post 21000955)
Why I am interested is because I am almost in the range for being a possible "lead pack or break away" finisher for the D riders in the ECCC (College cycling "league" in USA Cycling).

As a D collegiate racer, your primary focus should be on developing technique, strategy, and instincts. You already have a nice bike. A nicer bike would help, but a season of racing under your belt will completely change your thinking about what changes you'll eventually want to make when you upgrade (or if you upgrade, assuming you still want to race after a season).

I understand the eagerness to squeeze out every possible advantage when you're improving, but your money will buy a LOT more performance in a year or two, when you understand your strengths and weaknesses better and have more experience under your belt.

corkyflad 04-24-20 08:57 AM

I think my LBS would not like folks to post links to bikecalculator.com. In all seriousness though, this is a really interesting/eyeopening tool. As a 6'3" tall lanky guy, one of my many known racing problems that I have is getting my head / torso combo out of the wind effectively. I just never knew how much of a difference in MPH riding in the drops vs. on the hoods makes. This calculator clearly shows that instead of bike upgrades, I need to get to working on my position on the bike.


Is there any other advice and/or websites someone could recommend for getting someones body into a more aero in the drop position, other than getting forearms parallel to the ground / elbows 90 degrees, flatten the back as much as possible, and to relax the shoulders?

burnthesheep 04-24-20 12:49 PM


Originally Posted by corkyflad (Post 21436363)
I think my LBS would not like folks to post links to bikecalculator.com. In all seriousness though, this is a really interesting/eyeopening tool. As a 6'3" tall lanky guy, one of my many known racing problems that I have is getting my head / torso combo out of the wind effectively. I just never knew how much of a difference in MPH riding in the drops vs. on the hoods makes. This calculator clearly shows that instead of bike upgrades, I need to get to working on my position on the bike.


Is there any other advice and/or websites someone could recommend for getting someones body into a more aero in the drop position, other than getting forearms parallel to the ground / elbows 90 degrees, flatten the back as much as possible, and to relax the shoulders?

Take a fit while pedaling video and post it to Slowtwitch forums. Needs to be good light from the side view.

I'll say, to get comfy at it fit is the first part. The second part is spending hours riding like that at tempo and SS or doing your intervals in it. I see so many people ride totally upright all the time to train and ride solo. Then can't get down when they have to hammer for longer than a couple minutes.

I'll often ride a whole hour or two hour tempo/SS ride in machine gunner hoods position.

Bikecalculator is super basic, Chung method and best bike split or aeroweenie calculators are better.

Branko D 07-02-20 12:41 AM

One kilo of bike weight translates to about 1% faster (or slower) up the typical local moderate climb (which is about 6%). I've actually tested this, power meter on both, heavy touring bike vs light racing bike, results come out exactly as math predicts. So, there's not much in it, really.

At the end of the day, developing a lot of power is the most important bit of climbing (or riding) fast... which doesn't stop me from buying lightweight kit, though.

burnthesheep 07-02-20 06:08 AM

FWIW though, there's a logical limit to size and power. The curve on "more weight more power" doesn't keep going linearly forever.

Go look at the pack at almost any race. Especially the podium. There's upper limits on how useful your added weight and matching added power can get you. You don't really get faster being a fatty just for the sake of being a fatty thinking that the extra food and mass will yield endless power figures.

It's only a couple data points, but any weeknight worlds or race I've ever done that has any kind of "hill feature" that's steeper than 6% and longer than 45 seconds or so......the "big boys" wind up dragging ass up to the re-group stop sign a good bit behind. By big boys I don't mean a "Sagan" or even a trackie sprinter like Ed Clancy aren't even freaking 80kg. I'm talking the beer and pizza groupies more at 90 to 100kg.

For somebody that is a Cat 4/5 racer or slower, I still think weight management is a big deal.

And weight on a bike ain't going to cut it if you're 100kg's. That's one lousy kg perhaps out of 100. Laying off the pizza and beer will net you 10 to 20 kg's.

Have kids and pull a bike trailer when they're young and about 25 lbs or so and see how it feels to pull that up a hill!!!!! Then imagine having to do that every hill when riding in your races or groups!

ridethecliche 07-02-20 08:29 AM

My foray into collegiate D was on a 1984 steel trek that I built using used parts.

That 22 lb bike is fine. Go race. Have fun. Spend the money on stuff that breaks. Go from there.

If you can afford a nice new bike and want it so you can use the old one for rain rides/racing... have at it.

AlgarveCycling 07-10-20 01:16 AM


Originally Posted by mohamilton (Post 21433667)
Weight makes a huge difference! Light bikes are so much more fun to ride, they get to speed faster, climb better, make you want to go faster, bore your girlfriend, what's not to love?!

When I got my Trek Madone a month ago I marvelled at how it felt faster on the flats and I was able to sprint a whole lot better on it too. Given I am a sprint specialist in races, the Madone suits me. The power just goes down and I get maximum benefit for the watts I can produce. My Wilier just skips about and while it accelerates quickly, is generally skittish and doesn't put the power down as well.

I enjoy riding the Trek so much, I took it up a long climb on a Club ride last week. Felt good personally, hated the climb because of the bike. The Trek felt sluggish and heavy. Now, at 8.4kg, it isn't a weight-weenie lightweight albeit not particularly heavy either.

Yesterday I went on another Club ride and took my lighter, 5.8kg, Wilier. Having not ridden it since the arrival of the Trek, it was a revelation in acceleration on climbs and I set PR's on every segment of the 900m high, 18km climb we did.

The lighter bike felt wonderful on the climb and really proved to me that each bike has its place. The heavier, more aero Trek is my sprint and flat route choice and the Wilier my climbing bike. It was always intended to be this way, of course, but only experiencing both properly could I know for certain that there is a tangible difference and not just something one wants to believe.

Edited to add: I'm not heavy either, 65kg. My ideal race weight would be a couple of kg's lighter but not much more than that at my age so I'm not carrying too much extra.

Branko D 07-10-20 06:56 AM

2.6kg is a big chunk of weight to save, though, especially when you weight 65kg, the impact is going to be a bit bigger, then on a 70kg rider. Still, even if I bought a 5.8kg superlight climbing bike instead of my current bike (which is also 8.4kg, funny, that), I'd be looking at a saving of maybe 3% up the steeper local climbs, which would move me from somewhere in the middle of the list in local races to somewhere also in the middle of the list.... it's a really big chunk of cash for not a big difference in placement ;)

AlgarveCycling 07-11-20 12:20 AM


Originally Posted by Branko D (Post 21579532)
2.6kg is a big chunk of weight to save, though, especially when you weight 65kg, the impact is going to be a bit bigger, then on a 70kg rider. Still, even if I bought a 5.8kg superlight climbing bike instead of my current bike (which is also 8.4kg, funny, that), I'd be looking at a saving of maybe 3% up the steeper local climbs, which would move me from somewhere in the middle of the list in local races to somewhere also in the middle of the list.... it's a really big chunk of cash for not a big difference in placement ;)

True in terms of the impact to me, it is very tangible. Yes too, it is a lot to spend if it isn't disposable income for marginal gains.

I'm in the Veteran class now and feature in the Top 5 for my region, the difference to me could be a podium place and which one for a particular route. Of course, I still need to qualify that since no racing at the moment but I have seen it in KOM's. Some I just wasn't getting, a couple of seconds short, I have since achieved on the Trek. It isn't just the weight, it is the aero too and how that works in tandem with the weight.

Doge 07-11-20 06:34 PM

The winning riders did 24.5mph (taking it as fact) on pretty much dead flat (10' per lap) course in 1974. Today we'd see ~30. Some flat as fast as 32mph, and hilly can be 28 for U23 and juniors (USA adults are slower than the U23s).
These bikes were likely 7 pounds heavier than today's winners and less aero.

Anyway, we have to figure out how they are losing 5mph to today's fast flat crits. I think the weight matters a lot, as does the aerodynamics and ...these are fighting words, but I also don't think the fitness was near what it is now.


https://cimg1.ibsrv.net/gimg/bikefor...172f9c7d7c.png

big john 07-11-20 07:23 PM


Originally Posted by Doge (Post 21582343)

Nice man, Jerry Ash.

wktmeow 07-11-20 07:47 PM


Originally Posted by Doge (Post 21582343)
The winning riders did 24.5mph (taking it as fact) on pretty much dead flat (10' per lap) course in 1974. Today we'd see ~30. Some flat as fast as 32mph, and hilly can be 28 for U23 and juniors (USA adults are slower than the U23s).
These bikes were likely 7 pounds heavier than today's winners and less aero.

Anyway, we have to figure out how they are losing 5mph to today's fast flat crits. I think the weight matters a lot, as does the aerodynamics and ...these are fighting words, but I also don't think the fitness was near what it is now.


https://cimg1.ibsrv.net/gimg/bikefor...172f9c7d7c.png

Can't forget tires. I still remember feeling a very noticeable difference going from the stock tires (some lower end Vittorias, Rubino maybe?) on my first road bike to GP4000s.

Doge 07-11-20 10:32 PM


Originally Posted by wktmeow (Post 21582466)
Can't forget tires. I still remember feeling a very noticeable difference going from the stock tires (some lower end Vittorias, Rubino maybe?) on my first road bike to GP4000s.

The 70's tubular silks were about as good as what we have now. Clement Criterium Seta. 250g, $45 won the TDF on Bernard Thévenet's bike 1975. Those were used in USA crits by a lot of riders as the Vittoria and great cotton Continentals.

HTupolev 07-12-20 12:42 AM


Originally Posted by Doge (Post 21582343)
The winning riders did 24.5mph (taking it as fact) on pretty much dead flat (10' per lap) course in 1974. Today we'd see ~30. Some flat as fast as 32mph, and hilly can be 28 for U23 and juniors (USA adults are slower than the U23s).
These bikes were likely 7 pounds heavier than today's winners and less aero.

Anyway, we have to figure out how they are losing 5mph to today's fast flat crits. I think the weight matters a lot, as does the aerodynamics and ...these are fighting words, but I also don't think the fitness was near what it is now.


https://cimg1.ibsrv.net/gimg/bikefor...172f9c7d7c.png

If those numbers are real, and if there wasn't treacherous wind on that day, I'd be shocked if a large majority of the speed difference wasn't due to changes in racing strategy.

I routinely ride my grandfather's Fuji America, which was made in the 1970s, and which has received almost zero modernization besides SPD-SL pedals and unavoidable features on consumables (notably modern shift housing and hyperglide tooth profiling on the six-speed freewheel). Given the speeds that I can sustain on that thing - which are extremely close to what I do on my Emonda - I don't feel any hesitation in saying that an elite racer would have no trouble doing 24.5mph solo on flat ground for 100 minutes on actual racing bikes of similar vintage. The only way that a peloton of elite racers would fail to sustain higher speeds is if they were all desperately trying to avoid doing any kind of serious effort at the front.

Also, if we're talking about a bike+rider weight of 170lbs or thereabouts, and we're acknowledging that the modern weight savings is largely away from the rims thanks to today's aero rim profiles, there's basically no situation in which a 7-pound bicycle savings increases speed by more than 4% or so. 24.5->30 is a 22% speed increase. On a flat course, even if there's lots of cornering, a 7lb bicycle weight difference is pretty much in the noise when talking about that scale of difference.

Flatballer 07-12-20 07:13 AM

I'm guessing that's mostly a mix of tactics, better training these days, and better gearing/shifting speed.

Plus aero wheels probably.

Doge 07-12-20 09:56 AM


Originally Posted by HTupolev (Post 21582767)
If those numbers are real, and if there wasn't treacherous wind on that day, I'd be shocked if a large majority of the speed difference wasn't due to changes in racing strategy.

I routinely ride my grandfather's Fuji America, which was made in the 1970s, and which has received almost zero modernization besides SPD-SL pedals and unavoidable features on consumables (notably modern shift housing and hyperglide tooth profiling on the six-speed freewheel). Given the speeds that I can sustain on that thing - which are extremely close to what I do on my Emonda - I don't feel any hesitation in saying that an elite racer would have no trouble doing 24.5mph solo on flat ground for 100 minutes on actual racing bikes of similar vintage. The only way that a peloton of elite racers would fail to sustain higher speeds is if they were all desperately trying to avoid doing any kind of serious effort at the front.

Also, if we're talking about a bike+rider weight of 170lbs or thereabouts, and we're acknowledging that the modern weight savings is largely away from the rims thanks to today's aero rim profiles, there's basically no situation in which a 7-pound bicycle savings increases speed by more than 4% or so. 24.5->30 is a 22% speed increase. On a flat course, even if there's lots of cornering, a 7lb bicycle weight difference is pretty much in the noise when talking about that scale of difference.

There have been significant improvements in most athletic speeds, running, rowing etc. since the mid-70s. And racing styles have changed. Men and Women's fields often race entirely differently, so yea, they could have been sand bagging the whole time. It was one data point I had of pretty good local riders. Being familiar with current crit speeds it stood out to me. Any other data points out there?

IMO - a heavy bike results in about a 1 mph difference. .5mph due to physics and .5 mph due to physiological results - that net in going slower. But I also think those racers as a whole were not as fit and didn't train as much, as long or as scientifically.

Doge 07-12-20 03:20 PM

I just did this. These are not crits, rather the World Championships. I used them as they were the easiest to get data for. Speeds have not changed much at all in 6 hour races. I'm still looking for crit speeds which is now in the USA around 20-30+. Crit bikes are often lighter as no UCI limit.
https://cimg4.ibsrv.net/gimg/bikefor...60ae4d46a2.png


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