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Are Drop bars just an illusion for most?

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Are Drop bars just an illusion for most?

Old 09-19-19, 08:21 AM
  #451  
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Originally Posted by Metieval View Post
they are not the ones telling me it's stupid to ride in the drops. or the ones claiming that drop bars are an illusion.
My turn! Please quote anyone telling you that "it's stupid to ride in the drops". Most everyone I've seen posting say that they don't use them all the time. Many here don't find that to be detrimental to riding in any way.
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Old 09-19-19, 08:29 AM
  #452  
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Originally Posted by kingston View Post
There is no doubt that cornering at speeds far below the limit is much safer, but it's also slower. As with most things there are trade-offs, and each rider has to decide what's best for them. I corner faster than some people and slower than others, but I wouldn't accuse anyone of doing it wrong unless they were endangering other riders.
This is true and a good example of why the whole discussion about which position is better for braking is just personal perspective.

However, and not to disagree with what you said... to Elcruxio's point. His objection (which I also noted when the particular post happened) is that one can't really talk about how unsafe a hand position is and then promote a (relatively) unsafe braking technique on the other - which is what Terry did.

No doubt some advanced riders who are in a competition (or just wanting to go faster) compromise optimum safety for speed by braking through a curve but, in a general cycling forum, that's not really promoting a "best practice" which seemed to be the motivation for drops advocacy a few pages back. I think the objection was to the juxtaposition, not the technique itself.

If one really wanted to promote safe practices for descending I would say number one, before worrying about hand position or braking through a curve, would be to just slow down. Everything is so much easier if you are not pushing the bicycles design envelope to its limits. Ego is the most dangerous position for descending IMO.
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Old 09-19-19, 08:31 AM
  #453  
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so as someone who doesn't really descend aggressively, this is a stupid question, but how do you even determine what the traction limit of your tires is when cornering? like, do you start to feel it slipping away?
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Old 09-19-19, 08:31 AM
  #454  
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Originally Posted by kingston View Post
There is no doubt that cornering at speeds far below the limit is much safer, but it's also slower. As with most things there are trade-offs, and each rider has to decide what's best for them. I corner faster than some people and slower than others, but I wouldn't accuse anyone of doing it wrong unless they were endangering other riders.
This is true and a good example of why the whole discussion about which position is better for braking is just personal perspective.

However, and not to disagree with what you said... to Elcruxio's point. His objection (which I also noted when the particular post happened) is that one can't really talk about how unsafe a hand position is and then promote a (relatively) unsafe braking technique on the other - which is what Terry did.

No doubt some advanced riders who are in a competition (or just wanting to go faster) compromise optimum safety for speed by braking through a curve but, in a general cycling forum, that's not really promoting a "best practice" which seemed to be the motivation for drops advocacy a few pages back. I think the objection was to the juxtaposition, not the technique itself.

If one really wanted to promote safe practices for descending I would say number one, before worrying about hand position or braking through a curve, would be to just slow down. Everything is so much easier if you are not pushing the bicycles design envelope to its limits. Riding an over inflated ego is the most dangerous position for descending IMO.
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Old 09-19-19, 08:41 AM
  #455  
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Originally Posted by sheddle View Post
so as someone who doesn't really descend aggressively, this is a stupid question, but how do you even determine what the traction limit of your tires is when cornering? like, do you start to feel it slipping away?
Experience is everything. You’ll learn.
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Old 09-19-19, 08:47 AM
  #456  
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Originally Posted by pickettt View Post
Experience is everything. You’ll learn.
In my experience you have to crash every once in a while to really know where the limit is, which is a good reason to never test the limit.
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Old 09-19-19, 08:53 AM
  #457  
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yeah, that's what I kinda figured. on my old bike, I did get some warning when doing things like putting down too much power when cornering (on flats) but I had no idea how you did that on fast downhills other than incrementing until you crash, buy a new bike and don't go over that line again
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Old 09-19-19, 08:58 AM
  #458  
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I like my drop bars, and don't understand why anyone else wouldn't.
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Old 09-19-19, 09:01 AM
  #459  
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I enjoy switchback riding in the summer as we have some excellent ski hill type approaches. Great day trip cranking up the road and then descending.
I try to go fast but stay in control and because there are so many curves, after a while you get a feel for what the bike can do - but I wouldn't say I push it to the edge.

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Old 09-19-19, 09:52 AM
  #460  
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Wait! Putting my feet down isn't the best braking technique?! Who knew?I

Arcane fine points of braking technique is truly a thread hijack of the first order which might have been ok if this was a remotely interesting discussion.
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Old 09-19-19, 10:10 AM
  #461  
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Originally Posted by elcruxio View Post
Going through corners so fast you need to brake while cornering is safe?
Straw man fallacy.

Once more, braking in corners is safe, at low speeds and near the limits of traction. They physics of that is clear.

Say you're in the middle of a 0.9g turn, and you apply 0.2g of braking force. You'll skid out, right?

Wrong.

0.2g of braking in a 0.9g turn produces 0.92g of skid-out force -- an addition of a mere 0.02g and still well below the skid-out level.

Originally Posted by elcruxio View Post
If the aim is to go through corners safely, why risk it with dividing traction between braking and cornering?
False assumption. Braking in a turn is not risky, as demonstrated above.

Originally Posted by elcruxio View Post
...losing traction on either tire whilst doing a road descent is the last thing one wants. Hence braking with the rear tire whilst cornering is a bad idea.
More uninformed fear mongering. I use both front and rear brakes in every turn. Not using both brakes is a bad idea.
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Old 09-19-19, 10:16 AM
  #462  
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Originally Posted by Happy Feet View Post
promote a (relatively) unsafe braking technique on the other - which is what Terry did.
Wrong. Braking inside of a turn is not an unsafe technique.

Stop perpetuating a myth.

Originally Posted by Happy Feet View Post
If one really wanted to promote safe practices for descending I would say number one, before worrying about hand position or braking through a curve, would be to just slow down. Everything is so much easier if you are not pushing the bicycles design envelope to its limits. Riding an over inflated ego is the most dangerous position for descending IMO.
Going slower is always a good idea, if you are unsure of your skills. But telling people never to brake in a turn is almost as dangerous as saying never to use the front brake, because you'll catapult yourself over the bars.
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Old 09-19-19, 10:35 AM
  #463  
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Originally Posted by terrymorse View Post
Straw man fallacy.

Once more, braking in corners is safe, at low speeds and near the limits of traction. They physics of that is clear.

Say you're in the middle of a 0.9g turn, and you apply 0.2g of braking force. You'll skid out, right?

Wrong.

0.2g of braking in a 0.9g turn produces 0.92g of skid-out force -- an addition of a mere 0.02g and still well below the skid-out level.



False assumption. Braking in a turn is not risky, as demonstrated above.



More uninformed fear mongering. I use both front and rear brakes in every turn. Not using both brakes is a bad idea.
Just out of curiosity, how do you measure your braking and cornering forces and how do you relate those to brake lever pressure?

Also it'd be wise to refrain from yelling fallacy if you can't discuss without using them yourself. Also there exists a concept of reading between the lines and reading within context.

Subtle things these
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Old 09-19-19, 10:39 AM
  #464  
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Originally Posted by sheddle View Post
yeah, that's what I kinda figured. on my old bike, I did get some warning when doing things like putting down too much power when cornering (on flats) but I had no idea how you did that on fast downhills other than incrementing until you crash, buy a new bike and don't go over that line again
You can also listen to the tires. They sing when you get close to the safe limit of traction
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Old 09-19-19, 10:40 AM
  #465  
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Originally Posted by elcruxio View Post
Just out of curiosity, how do you measure your braking and cornering forces and how do you relate those to brake lever pressure?
Through feel, by acquiring braking skills at a young age, then practicing for a lifetime.
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Old 09-19-19, 10:42 AM
  #466  
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Originally Posted by terrymorse View Post
Through feel, by acquiring braking skills at a young age, then practicing for a lifetime.
I meant how do you accurately measure whether you're cornering at say 0.9g and braking at 0.2g? Do you have a garmin unit that tells you or...?
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Old 09-19-19, 11:08 AM
  #467  
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Originally Posted by Happy Feet View Post
This is true and a good example of why the whole discussion about which position is better for braking is just personal perspective.

However, and not to disagree with what you said... to Elcruxio's point. His objection (which I also noted when the particular post happened) is that one can't really talk about how unsafe a hand position is and then promote a (relatively) unsafe braking technique on the other - which is what Terry did.

No doubt some advanced riders who are in a competition (or just wanting to go faster) compromise optimum safety for speed by braking through a curve but, in a general cycling forum, that's not really promoting a "best practice" which seemed to be the motivation for drops advocacy a few pages back. I think the objection was to the juxtaposition, not the technique itself.

If one really wanted to promote safe practices for descending I would say number one, before worrying about hand position or braking through a curve, would be to just slow down. Everything is so much easier if you are not pushing the bicycles design envelope to its limits. Riding an over inflated ego is the most dangerous position for descending IMO.
From what I've read, braking in a corner (actually braking once the bicycle is traversing the corner as opposed to braking BEFORE entering the curve) is learned skill and more so the faster one is riding. I recall reading about a woman who brake hard in a corner whilst descending and the bike straightened up to a vertical position and she went over the edge of the road and down the hill/mountain. She did not have the skill needed to brake whilst riding THROUGH a corner or curve at speed.

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Old 09-19-19, 11:10 AM
  #468  
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Originally Posted by sheddle View Post
so as someone who doesn't really descend aggressively, this is a stupid question, but how do you even determine what the traction limit of your tires is when cornering? like, do you start to feel it slipping away?
From what I've seen and experienced in corners, once the tire starts to slip, unless you are very skilled/luck you go down as you can't recover. I think that's the MAIN reason people advise others to not brake once they've entered a corner or curve.

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Old 09-19-19, 11:11 AM
  #469  
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Originally Posted by elcruxio View Post
I meant how do you accurately measure whether you're cornering at say 0.9g and braking at 0.2g? Do you have a garmin unit that tells you or...?
I don't measure my braking or cornering forces, what a silly question. But I see what you're doing.

The trigonometry problem I presented used numbers to illustrate that even when approaching the limits of traction, that braking in a turn is safe.

But your argument tactic is clear. You select the fact that those numbers that aren't being measured to discredit braking in a turn as a safe technique. It didn't work.

"Why brake in the turn? If all braking is done before the turn, speed will be slower than necessary before the apex. Anticipating maximum speed for the apex is difficult, and because the path is not a circular arc, speed must be trimmed all the way to that point. Fear of braking in curves usually comes from an incident of injudicious braking at a point where braking should have been done with a gentle touch to match the conditions." -- Jobst Brandt
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Old 09-19-19, 11:25 AM
  #470  
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Originally Posted by Commutess View Post
Drop bars have only one more position than flat-bars with bar-ends, and that is the drops. And the drops can be very uncomfortable for a lot of people. Braking on the hoods, and in the drops both have their challenges. Using flat-bars, you can very easily get on the grips and have full braking using one or two fingers. I think that going up an incline with flat-bars is easier than drop-bars because when you use the bar ends you can really swing the bike back and forth while standing. I also think that bar-ends are an absolute must on flat/riser bars.
Posting this just for those who might be following this thread looking for information.

I was out on my cantilever brake calipers and Tiagra Aero brake levers (not Brifters) DROPBAR MTB today and whilst braking from the hoods and using JUST TWO FINGERS to do so proved again that i can easily skid my rear wheel. Ditto for riding down a dirt or gravel trail = two-fingers will easily cause the rear wheel to skid/slide.

Here's the bike I was riding.




Cheers
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Old 09-19-19, 11:39 AM
  #471  
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Originally Posted by terrymorse View Post
I don't measure my braking or cornering forces, what a silly question. But I see what you're doing.

The trigonometry problem I presented used numbers to illustrate that even when approaching the limits of traction, that braking in a turn is safe.

But your argument tactic is clear. You select the fact that those numbers that aren't being measured to discredit braking in a turn as a safe technique. It didn't work.

"Why brake in the turn? If all braking is done before the turn, speed will be slower than necessary before the apex. Anticipating maximum speed for the apex is difficult, and because the path is not a circular arc, speed must be trimmed all the way to that point. Fear of braking in curves usually comes from an incident of injudicious braking at a point where braking should have been done with a gentle touch to match the conditions." -- Jobst Brandt
You keep throwing out numbers and jobst brandt quotes but you don't really specify your arguments other than something is safe and something else is unsafe.

Could you explain the whole cornering maths like you were explaining it to say, a complete layman? How exactly does it work out? I'm all ears.
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Old 09-19-19, 11:52 AM
  #472  
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I usually just straighten out my line (if practical) and brake gently
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Old 09-19-19, 12:12 PM
  #473  
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Originally Posted by elcruxio View Post
Could you explain the whole cornering maths like you were explaining it to say, a complete layman?
Okay, I'll try to explain it using only high school level math.

When braking, there is a force generated on the tire-road interface that is in the direction of travel.

When turning, there is a force generated on the tire-road interface that is perpendicular to the direction of travel.

We call these two forces vectors, as they have each a value and a direction.

When both braking and turning, the resulting force at the tire-road interface is the sum of these two force vectors. But since the turning and braking vectors are perpendicular to each other, they can be combined using the Pythagorean Theorem (which should familiar to any high school student):

Where:
a = turning force
b = braking force
c = combined force

As I wrote in my example earlier, pick a turning force of a very substantial 0.9g, and the braking force a substantial 0.2g.

The combined force at the tire-road interface in this case is:

square root of [ cornering force squared + braking force squared ], or

SQRT[ 0.9^2 + 0.2^2 ] =

SQRT[ 0.81 + 0.04 ] =

SQRT[ 0.85 ] = 0.92

This example demonstrates that even when turning at 0.9 g, and braking with 0.2 g, the force at the tire-road interface only increases by 0.02g.

As shown, substantial braking can be done in a turn with very little increase in tire-road force, and thus the warning that braking in a turn substantially increases the risk of slipping out has no merit.
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Old 09-19-19, 12:40 PM
  #474  
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Originally Posted by cyccommute View Post
You mean like



Or this



or this
If I said "riding without hands is a good way to crash"
Is that saying "you will crash", if you ride without hands?

NO SIR it is not ! So Quit twisting words.

the same applies to handlebars, one way leaves your self open to a crash, it doesn't mean that you will crash.

2 groups of people, those who elect to ride drops on a dropbar, and those who claim "that is not my Drop bar!!!!"
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Old 09-19-19, 01:13 PM
  #475  
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Originally Posted by terrymorse View Post
Okay, I'll try to explain it using only high school level math.

When braking, there is a force generated on the tire-road interface that is in the direction of travel.

When turning, there is a force generated on the tire-road interface that is perpendicular to the direction of travel.

We call these two forces vectors, as they have each a value and a direction.

When both braking and turning, the resulting force at the tire-road interface is the sum of these two force vectors. But since the turning and braking vectors are perpendicular to each other, they can be combined using the Pythagorean Theorem (which should familiar to any high school student):

Where:
a = turning force
b = braking force
c = combined force

As I wrote in my example earlier, pick a turning force of a very substantial 0.9g, and the braking force a substantial 0.2g.

The combined force at the tire-road interface in this case is:

square root of [ cornering force squared + braking force squared ], or

SQRT[ 0.9^2 + 0.2^2 ] =

SQRT[ 0.81 + 0.04 ] =

SQRT[ 0.85 ] = 0.92

This example demonstrates that even when turning at 0.9 g, and braking with 0.2 g, the force at the tire-road interface only increases by 0.02g.

As shown, substantial braking can be done in a turn with very little increase in tire-road force, and thus the warning that braking in a turn substantially increases the risk of slipping out has no merit.
I'll have to get back to this after I discuss it with a friend who's a math wiz but at first glance the formula seems too simplistic to factor in all relevant forces. Just the formulae for cornering forces without braking are much more advanced as are pure braking force calculations.

I suspect that there are a few more vectors involved as well.

Also the numbers are off which makes me heavily suspect the whole validity of Brandts expertise on the matter. Cornering at 0.9g's with a bicycle is unlikely if not impossible altogether. Racing motorcycles with specially formulated sticky hot tires on hot tarmac can reach 1g or even go just above it. However for a bicycle I'd say the theoretical maximum cornering force is below 0.8g's as that's within the typical coefficient of friction achieved with bicycle tyres on tarmac.

It's wholly beside the point but considering that brandts example rider would have wiped out before he ever touched the brakes just takes a good chunk of validity out of his argument.
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