The Great Braking Debate Thread (Disc/Rim/Cantilever/Fixie/InsertNewTechHere)

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mgrl
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by mgrl

He's put on 20kg so his w/kg is not so good, even if his absolute power output is still up there

by Weenie


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blutto
Posts: 229
Joined: Thu Jun 21, 2012 5:09 pm

by blutto

mgrl wrote:
Wed Nov 24, 2021 2:34 pm
He's put on 20kg so his w/kg is not so good, even if his absolute power output is still up there
OK, so he has put on some weight....well take out the extra stuff he has in the trunk and look at how the motive bits perform at the new weight....btw he actually looks to have gained only about 12kg since his salad days....so if one were to re-jig the numbers to take that into account his w/kg seems more like about 5.6....

But what I found really interesting was the last line, the bolded one....which, on first blush at least , seems to indeed indicate a lot of people here could go off to Europe and live the dream and become pro cyclists...though it could also be that I am just misreading something, like the correct adjustment for the ever-present Internet Power Factor thingee...

Cheers

mgrl
Posts: 340
Joined: Wed Nov 25, 2020 12:49 am

by mgrl

blutto wrote:
Wed Nov 24, 2021 3:39 pm
But what I found really interesting was the last line, the bolded one....which, on first blush at least , seems to indeed indicate a lot of people here could go off to Europe and live the dream and become pro cyclists...though it could also be that I am just misreading something, like the correct adjustment for the ever-present Internet Power Factor thingee...
If you can put out 450W aerobic at 80kg then sure, but a) tall, heavy guys have lesser W/kg than smaller guys because W tends to scale with height squared and kg with height cubed and b) the people putting out 5W/kg tend to be in the 50-70kg range, making it more like 250-350W, and c) Aero drag also scales with height squared, so pure w/kg is only important on the slower climbs. As Tobin posted earlier, a tiny guy with 4W/kg is going to get destroyed by a tall guy with 4W/kg on a flat course.

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Matt28NJ
Posts: 259
Joined: Tue Jul 14, 2009 3:16 am

by Matt28NJ

blutto wrote:
Wed Nov 24, 2021 3:39 pm
But what I found really interesting was the last line, the bolded one....which, on first blush at least , seems to indeed indicate a lot of people here could go off to Europe and live the dream and become pro cyclists...though it could also be that I am just misreading something, like the correct adjustment for the ever-present Internet Power Factor thingee...

LMAO, 100% to that Blutto.

What matters is race results - whatever type of racing you do... it's all good!

It's also cool that you or your buddy took a well known (in your own little local sandbox, anyway) Strava segment. But can you do it an hour or two into a race? That's what impresses folks more.

Hey, no knock on Strava, I'm on there too, I don't check it much... it is a fun social connector, not an arbiter of deciding who is fast. I even have a couple of silly KOMs that I don't deserve, like the sprint finish for our state championship crit a few years ago. Yeah, I had the fastest sprint, but barely finished in the top 10 out of 50 or so racers, got no prize money and no upgrade points. Gotta take it all in context. What was that KOM worth, really?

Anyhow, the d**k waving contest is silly. Come out and pin on a number and have fun is what I tell people when they start comparing FTPs.

TobinHatesYou
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by TobinHatesYou

blutto wrote:
Wed Nov 24, 2021 3:39 pm
mgrl wrote:
Wed Nov 24, 2021 2:34 pm
He's put on 20kg so his w/kg is not so good, even if his absolute power output is still up there
OK, so he has put on some weight....well take out the extra stuff he has in the trunk and look at how the motive bits perform at the new weight....btw he actually looks to have gained only about 12kg since his salad days....so if one were to re-jig the numbers to take that into account his w/kg seems more like about 5.6....

But what I found really interesting was the last line, the bolded one....which, on first blush at least , seems to indeed indicate a lot of people here could go off to Europe and live the dream and become pro cyclists...though it could also be that I am just misreading something, like the correct adjustment for the ever-present Internet Power Factor thingee...

Cheers

Indurain put out 510W for his hour record. At 80kg that’s 6.375w/kg. At 85kg, that’s still 6.0w/kg. Either number is believable. Those are incredible numbers for a big man. At 6.375w/kg and 80kg, you would be able to kill 60kg climbers on a flat, and still keep pace with fresh ones on climbs.

I know 5w/kg is tough to wrap your head around if you’ve never been close, but this is bell curve stuff. 5w/kg puts you around 97th percentile, so yeah 3 out of 100 males who try will get there. That’s good, but obviously not pro. 1 in 20 males have achieved 4.8w/kg according to one of the training platforms I’ve used.

jasjas
Posts: 439
Joined: Sun Aug 23, 2009 10:15 am

by jasjas

TobinHatesYou wrote:
Wed Nov 24, 2021 6:09 pm
blutto wrote:
Wed Nov 24, 2021 3:39 pm
mgrl wrote:
Wed Nov 24, 2021 2:34 pm
He's put on 20kg so his w/kg is not so good, even if his absolute power output is still up there
OK, so he has put on some weight....well take out the extra stuff he has in the trunk and look at how the motive bits perform at the new weight....btw he actually looks to have gained only about 12kg since his salad days....so if one were to re-jig the numbers to take that into account his w/kg seems more like about 5.6....

But what I found really interesting was the last line, the bolded one....which, on first blush at least , seems to indeed indicate a lot of people here could go off to Europe and live the dream and become pro cyclists...though it could also be that I am just misreading something, like the correct adjustment for the ever-present Internet Power Factor thingee...

Cheers

Indurain put out 510W for his hour record. At 80kg that’s 6.375w/kg. At 85kg, that’s still 6.0w/kg. Either number is believable. Those are incredible numbers for a big man. At 6.375w/kg and 80kg, you would be able to kill 60kg climbers on a flat, and still keep pace with fresh ones on climbs.

I know 5w/kg is tough to wrap your head around if you’ve never been close, but this is bell curve stuff. 5w/kg puts you around 97th percentile, so yeah 3 out of 100 males who try will get there. That’s good, but obviously not pro. 1 in 20 males have achieved 4.8w/kg according to one of the training platforms I’ve used.
5wpk isn't out of this world at all, articles i have read, usually put a pro cyclist at around 5.7wpk +, its getting from that to 6 ish that is the problem, plus being able to do it (and a lot more) after 4 to 6 hours of racing.

Again, though interesting, don't see the releveance to this thread........

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neeb
Posts: 1101
Joined: Tue Jan 27, 2009 8:19 pm

by neeb

jasjas wrote:
Wed Nov 24, 2021 7:03 pm
Again, though interesting, don't see the releveance to this thread........
My honest impression is that there's no relationship whatsoever, and that there are people on both sides of the rim/disc thing at all performance/experience levels.

So what are the demographics of this, if any..? Old vs. young? Poor vs. rich? Light body weight vs. heavy? Aesthete vs. tech. nerd?

Let's try to avoid overly-negative stereotyping of the opposing camp.. :wink:

stevesbike
Posts: 324
Joined: Thu Oct 24, 2019 5:33 pm

by stevesbike

TobinHatesYou wrote:
Wed Nov 24, 2021 9:22 am
jasjas wrote:
Wed Nov 24, 2021 9:09 am
Who cares what wpk someone has or hasn't, its a total irrelevance to this thread, go post in Training?

It pertains to this thread as a few rim-brake aficionados periodically claim that disc-brake owners are "cafe warriors" or don't "push their hardware."
Strava has data on more than 70 million users, and it's clear from it that most cyclists don't 'push their hardware.' Most do not log huge miles and most do not speed down long, technical descents. From that data (used in a number of peer-reviewed papers), it's obvious that the supposed advantages of disc brakes are not even relevant to the typical consumer. It's a bad argument to make, and watts/kg, what brake a GC contender chooses on a mountain stage, etc. have virtually no relevance for the typical consumer.

blutto
Posts: 229
Joined: Thu Jun 21, 2012 5:09 pm

by blutto

TobinHatesYou wrote:
Wed Nov 24, 2021 6:09 pm
blutto wrote:
Wed Nov 24, 2021 3:39 pm
mgrl wrote:
Wed Nov 24, 2021 2:34 pm
He's put on 20kg so his w/kg is not so good, even if his absolute power output is still up there
OK, so he has put on some weight....well take out the extra stuff he has in the trunk and look at how the motive bits perform at the new weight....btw he actually looks to have gained only about 12kg since his salad days....so if one were to re-jig the numbers to take that into account his w/kg seems more like about 5.6....

But what I found really interesting was the last line, the bolded one....which, on first blush at least , seems to indeed indicate a lot of people here could go off to Europe and live the dream and become pro cyclists...though it could also be that I am just misreading something, like the correct adjustment for the ever-present Internet Power Factor thingee...

Cheers

Indurain put out 510W for his hour record. At 80kg that’s 6.375w/kg. At 85kg, that’s still 6.0w/kg. Either number is believable. Those are incredible numbers for a big man. At 6.375w/kg and 80kg, you would be able to kill 60kg climbers on a flat, and still keep pace with fresh ones on climbs.

I know 5w/kg is tough to wrap your head around if you’ve never been close, but this is bell curve stuff. 5w/kg puts you around 97th percentile, so yeah 3 out of 100 males who try will get there. That’s good, but obviously not pro. 1 in 20 males have achieved 4.8w/kg according to one of the training platforms I’ve used.
So believe lab testing with the subject in situ ( and a peer reviewed published paper )...or interwebs you and one of your training platforms...hmmm, tough call that....

Cheers

maxim809
Administrator
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by maxim809

My review of this thread thus far:

People putting things into perspective by framing their arguments with details & context:
Most are actually doing alright!

B-, pretty good!!

People agreeing on what context is actually "correct and "representative" of whether red or blue is a prettier color:
The never ending roflcopter circular battle.

flying
Posts: 2861
Joined: Mon Dec 19, 2005 9:16 am

by flying

robbosmans wrote:
Wed Nov 24, 2021 9:11 am
Which probably means there isn’t anything relevant to talk about
That was actually true on page 1....91 pages ago
Since then it is just the usual he said/she said & I need to drive my post count higher & higher :noidea:

mgrl
Posts: 340
Joined: Wed Nov 25, 2020 12:49 am

by mgrl

stevesbike wrote:
Wed Nov 24, 2021 8:44 pm
Strava has data on more than 70 million users, and it's clear from it that most cyclists don't 'push their hardware.' Most do not log huge miles and most do not speed down long, technical descents. From that data (used in a number of peer-reviewed papers), it's obvious that the supposed advantages of disc brakes are not even relevant to the typical consumer. It's a bad argument to make, and watts/kg, what brake a GC contender chooses on a mountain stage, etc. have virtually no relevance for the typical consumer.
The claim wasn't "people need disc brakes because they push their hardware" or "people need rim brakes because they push their hardware", it was "no people who support disc brakes push their hardware". That is disproved by the existance of at least one person who supports disc brakes pushing their hardware.
blutto wrote:
Wed Nov 24, 2021 8:49 pm
So believe lab testing with the subject in situ ( and a peer reviewed published paper )...or interwebs you and one of your training platforms...hmmm, tough call that....
Peer review only gets you so far - eg, here's a peer reviewed paper that claims that the novel coronavirus came from space, which has made the journal that published it a laughing stock : https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7358766/ . Obviously that's an extreme example, but the point is that you shouldn't take all "peer reviewed" claims uncritically.

I had a look at the paper (Mujika I, The cycling physiology of Miguel Indurain 14 years after retirement. Int J Sports Physiol Perform. 2012 Dec;7(4):397-400), and the version of the claim in the main text is:
Despite the observed decline, the absolute maximal and submaximal power output and VO2 values of Miguel Indurain are still impressive and similar to values exhibited by active male professional cyclists tested with similar protocols.9,11
Citation 9 is "Santalla A, Naranjo J, Terrados N. Muscle efficiency improves over time in world-class cyclists. Med Sci Sports Exerc. 2009;41:1096–1101.", but this paper doesn't study power outputs - it's about VO2 max.

Citation 11 is "Padilla S, Mujika I, Cuesta G, Goiriena JJ. Level ground and uphill cycling ability in professional road cycling. Med Sci Sports Exerc. 1999;31;878–885." This one does measure power outputs using a similar but not identical testing protocol, with participants divided into categories based on their specialty (Uphill (UH), Time Trial (TT), Flat Terrain (FT) and All Terrain (AT)). Let's see what numbers they get:
When expressed relative to body mass, UH presented the highest Wmax (6.47 ± 0.33 W·kg−1), followed by TT, AT, and FT (6.41 ± 0.12, 6.35 ± 0.18 and 6.04 ± 0.29 W·kg−1, respectively).
The Mujika paper says that Indurain's 4.88W/kg is similar to 6-6.5W/kg, this is clearly nonsense. The testing appears fine, the comparative claim is unsupported. This kind of thing happens all the time and is why it's so important to actually follow up citations. People don't, but they should.

bikeboy1tr
Posts: 1395
Joined: Thu Mar 21, 2013 3:19 am
Location: Southern Ontario Canada

by bikeboy1tr

Actually many that I follow on Strava are pretty amazing athletes and do ride the wheels off their bikes and often.Many are locals who can put out some big power numbers not all are riding disc bikes but many of them do so that discounts the cafe warriors who only ride disc in my area. Some I follow ride the Hautes in Europe and do well but most are riding our Nationals and provincials and whatever they can get to in the States.
Indurain was the first cycling athlete that made me want to watch the tour as I first started riding bicis because he was the big guy performing in the mountains with most of the little climbers. Indurain also had lungs down to his toes.
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mgrl
Posts: 340
Joined: Wed Nov 25, 2020 12:49 am

by mgrl

For reference, Indurain did a similar test in 1995 and got about 7W/kg, ludicrous numbers (for full context, the 4.88, the 6-6.5s and the 7 aren't for FTP, but are the maximal w/kg averages over one interval length for a 3 or 4 minute-step ramp test. The full testing protocols are in the respective papers.)

by Weenie


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robertbb
Posts: 2179
Joined: Thu Jul 23, 2009 3:35 am

by robertbb

basilic wrote:
Wed Nov 24, 2021 8:54 am
TobinHatesYou wrote:
Wed Nov 24, 2021 6:06 am
riding at MLSS to TTE.
would you translate that pls? and whatever it is, how is it measured?
Look up videos on TTE, Stamina, FTP, Vo2 max, etc from Tim Kusick (the mastermind behind WKO5).

That'll explain it.

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