2022 PRO Thread

Questions about bike hire abroad and everything light bike related. No off-topic chat please

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Karvalo
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by Karvalo

Mr.Gib wrote:
Sun May 29, 2022 5:32 am
Ask yourself why riders are sticking their inside knee out. Other than to catch wind and provide air braking, doing so only interferes with the bodies ability to maintain good traction, adjust position and balance against the road contact point.
Do you think you are better at cornering than Nibali?

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micky
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by micky

Been this morning at the Giro stage area in Verona, I was able to get into the restricted teams area.
Didn't see anything unusual or new, but it was interesting to see at Astana team a road bike next to a TT bike with both wheels with tires reporting 28 but the one on the road bike was massive compared to the one on the TT bike and I would guess a "fake label".

Mr.Gib
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by Mr.Gib

Karvalo wrote:
Sun May 29, 2022 11:50 am
Mr.Gib wrote:
Sun May 29, 2022 5:32 am
Ask yourself why riders are sticking their inside knee out. Other than to catch wind and provide air braking, doing so only interferes with the bodies ability to maintain good traction, adjust position and balance against the road contact point.
Do you think you are better at cornering than Nibali?

Image
Interesting reaction to the question. It's not relevant how good I think I am. Can you answer the question? What, according to the laws of physics, are the advantages or disadvantages of that position. Does it improve traction? Aerodynamics? line control? Or do we just do it because everyone before us did it? They got down the hill OK so why not, right?

I once asked a very experienced resident of the alps and very good descender about "the knee". His answer was that the middle of the tire had better grip so he wanted to keep the bike upright. It is the only answer I have ever heard and one I do not accept. Regardless of body position, there is a force vector throught the center of mass of the system to the tire contact patch. The only way the traction argument would hold up was if the center of the tread was a grippier compount than closer to the edge - the opposite of what some manufacturers create.

So again, what is the advantage of "the knee"?
wheelsONfire wrote: When we ride disc brakes the whole deal of braking is just like a leaving a fart. It happens and then it's over. Nothing planned and nothing to get nervous for.

skinnybex
Posts: 37
Joined: Wed Oct 20, 2021 4:07 pm

by skinnybex

Mr.Gib wrote:
Sun May 29, 2022 3:56 pm
Karvalo wrote:
Sun May 29, 2022 11:50 am
Mr.Gib wrote:
Sun May 29, 2022 5:32 am
Ask yourself why riders are sticking their inside knee out. Other than to catch wind and provide air braking, doing so only interferes with the bodies ability to maintain good traction, adjust position and balance against the road contact point.
Do you think you are better at cornering than Nibali?

Image
Interesting reaction to the question. It's not relevant how good I think I am. Can you answer the question? What, according to the laws of physics, are the advantages or disadvantages of that position. Does it improve traction? Aerodynamics? line control? Or do we just do it because everyone before us did it? They got down the hill OK so why not, right?

I once asked a very experienced resident of the alps and very good descender about "the knee". His answer was that the middle of the tire had better grip so he wanted to keep the bike upright. It is the only answer I have ever heard and one I do not accept. Regardless of body position, there is a force vector throught the center of mass of the system to the tire contact patch. The only way the traction argument would hold up was if the center of the tread was a grippier compount than closer to the edge - the opposite of what some manufacturers create.

So again, what is the advantage of "the knee"?
The inside knee pointing out is a product of the outside leg applying pressure to the pedals and allowing the tire shoulder contact patch to hold grip better through a turn at more extreme lean angles....which equates to a faster line holding more speed through a turn whether banked or flat. The inside knee flaring out is perfect techniqe because it allows body to bike seperation which allows the rider to lay the bike over - more sideways and carve the turn. Likely way less speed scubbed means more speed and not pushing wide through a turn. Your tire isn't optimized to grip in the center tread when turning on more aggressive and fast downhill sections. You can debate aerodynamic and air brake efficency all you want but the facts remain this is the tried and true techniqe in any MTB and even motogp rider thats skilled and proficent in descending.
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skinnybex
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by skinnybex

I'd like to think this is picture perfect techniqe for both being fast and effecient through a turn at higher speeds. Not all road tires have shoulder siping but look at a tire like the Conty GP5000 and that aides in turning traction.
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Miller
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by Miller

Sipes are meaningless for road tyres, they're only there for branding and to make worried riders feel better. Inside knee out just looks to me like a habit riders get into which is neither disadvantageous nor beneficial.

flying
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by flying

micky wrote:
Sun May 29, 2022 3:37 pm
Been this morning at the Giro stage area in Verona, I was able to get into the restricted teams area.
Didn't see anything unusual or new, but it was interesting to see at Astana team a road bike next to a TT bike with both wheels with tires reporting 28 but the one on the road bike was massive compared to the one on the TT bike and I would guess a "fake label".

Your so lucky to be able to go to a stage :thumbup:

On the tire probably true "fake label" or could the road bike have a more narrow rim giving that look?

skinnybex
Posts: 37
Joined: Wed Oct 20, 2021 4:07 pm

by skinnybex

Miller wrote:
Sun May 29, 2022 5:48 pm
Sipes are meaningless for road tyres, they're only there for branding and to make worried riders feel better. Inside knee out just looks to me like a habit riders get into which is neither disadvantageous nor beneficial.
I'm guessing most hobby level road riders believe what you stated and are likely not much more than cardio/power riders or have never ridden mountain bikers with good fundamentals. Go watch some youtube videos of Criterium racing which is generally fast flat corners where the speeds are between 25-40mph. It's a skill which involves many nuances to turn flat out without the need to scrub speed with your brakes. If you don't understand traction and cornering skills you'll yoyo and waste 25-30% more than a rider who carries speed. The same goes on fast banked descents where these Pro's are topping out at 64-80kmph and that can make the difference while gapping less skilled riders.

Congratulation to Jai Hindley for finally making the move to gap Carapaz and win the Giro. He's a top 5 climber in the World Tour so hopefully we see him at the Vuelta but his TT is not good enough for the TDF.
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blaugrana
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by blaugrana

Also depending on the rider and bike fit, there can be some significant overlap between knee and elbow, so the knee out allows you to avoid that overlap and have a cornering position that lets you make small adjustments in the position of the body. In terms of the physics, of course as long as the center of mass is at the same place and the forces at the contact points are the same, the rest doesn't really matter that much, so you just need a position that allows you to control this factors comfortably and accurately.

TobinHatesYou
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by TobinHatesYou

Miller wrote:
Sun May 29, 2022 5:48 pm
Sipes are meaningless for road tyres, they're only there for branding and to make worried riders feel better. Inside knee out just looks to me like a habit riders get into which is neither disadvantageous nor beneficial.

Your inside pedal is up so your knee is going to be bent. Pushing the knee outboard keeps the entire inside leg stable and tight. And when I’m cornering at speed I definitely don’t want my knee knocking around causing even slight shifts in CoG.

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HammerTime2
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by HammerTime2

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What is the deal here?

maquisard
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by maquisard

Doping induced aggression from Lemond.

TobinHatesYou
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by TobinHatesYou

Mr.Gib wrote:
Sun May 29, 2022 3:56 pm

So again, what is the advantage of "the knee"?

He’s keeping his inside leg rigid in the easiest way possible. Look at his calf muscle. Try it sometime.

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tymon_tm
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by tymon_tm

TobinHatesYou wrote:
Sun May 29, 2022 6:50 pm
Miller wrote:
Sun May 29, 2022 5:48 pm
Sipes are meaningless for road tyres, they're only there for branding and to make worried riders feel better. Inside knee out just looks to me like a habit riders get into which is neither disadvantageous nor beneficial.

Your inside pedal is up so your knee is going to be bent. Pushing the knee outboard keeps the entire inside leg stable and tight. And when I’m cornering at speed I definitely don’t want my knee knocking around causing even slight shifts in CoG.
^this

bending inside knee is just *natural*, cant think of any other way to position a leg in a fast corner :noidea:
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Roel W
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by Roel W

I thought Lotto-Soudal was riding Shimano this year.....
Picture from today's Giro time trial stage.
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