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wut?
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From http://sheldonbrown.com/cantilever-geometry.html

"Feel" vs. Function

With automobile brakes, a nice "hard" pedal feel is a sign that the brakes are in good condition. A soft, "spongy" feel at the brake pedal is a sign of trouble, perhaps air in the hydraulic lines. This is not the case with bicycle brakes. A hard, crisp feel to the brakes on a bicycle may be a sign that the brakes don't have much mechanical advantage. You squeeze them until the brake shoes hit the rim, then they stop. Brakes with a high mechanical advantage will feel "spongy" by comparison, because the large amount of force they deliver to the brake shoes will squash the shoes against the rim, deforming them temporarily under pressure. You can feel this deformation in your fingers. The brakes with the rock-hard feel may seem nice on the work stand or the showroom floor, but when it comes to making the bike actually stop, the spongy set-up will do the job better, with less finger pressure and greater margin for safety in wet conditions.


Do y'all agree. If this is true, does that mean spongy Shimano Sora/Tiagra brakes are actually better than crisp Dura Ace brakes? Something doesn't add up...
 

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Resident Dutchbag
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I'm afraid the good man says spongy brakes where he means soft brake pads. He's a little too eager being revisionist about things is all.
 

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wut?
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Discussion Starter · #3 ·
rogger said:
I'm afraid the good man says spongy brakes where he means soft brake pads. He's a little too eager being revisionist about things is all.
That would make more sense. If the spongy feeling is flexing in the caliper, that is definitely not better.

You so smart.
 

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You have Dura Ace Cantis?

Cantis are specifically what he was referring to...and for once, I agree with him LOL.
 

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Call me a Fred
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I have a spongy brain. Should I also have spongy brakes?
 

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Fini les ecrase-"manets"!
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Scotty2Hotty said:
From http://sheldonbrown.com/cantilever-geometry.html

"Feel" vs. Function

With automobile brakes, a nice "hard" pedal feel is a sign that the brakes are in good condition. A soft, "spongy" feel at the brake pedal is a sign of trouble, perhaps air in the hydraulic lines. This is not the case with bicycle brakes. A hard, crisp feel to the brakes on a bicycle may be a sign that the brakes don't have much mechanical advantage. You squeeze them until the brake shoes hit the rim, then they stop. Brakes with a high mechanical advantage will feel "spongy" by comparison, because the large amount of force they deliver to the brake shoes will squash the shoes against the rim, deforming them temporarily under pressure. You can feel this deformation in your fingers. The brakes with the rock-hard feel may seem nice on the work stand or the showroom floor, but when it comes to making the bike actually stop, the spongy set-up will do the job better, with less finger pressure and greater margin for safety in wet conditions.


Do y'all agree. If this is true, does that mean spongy Shimano Sora/Tiagra brakes are actually better than crisp Dura Ace brakes? Something doesn't add up...
He doesn't have it completely right, or at least isn't explaining it clearly, but the basis is correct as I understand such things. And your question isn't really about the same thing as what he's talking about.

When the brakes have a greater mechanical advantage, the lever will feel spongier. This sponginess is actually what it feels like to have some modulation in your braking--you have more levels of force available between "no brakes" and "full stop." When the brakes engage as soon as you touch the lever, you basically have all or none, with nothing between. This does not mean that your brakes will necessarily stop the bike better when your levers feel spongier, as Sheldon implies. What it means is that you will probably be able to apply more force to the brake pads at your maximum "squeeze," and you will also be able to more easily modulate your braking force, meaning you can use your brakes more effectively.

What you're asking is totally different. A crappy brake that's not rigid will not work as well as one that engages positively and doesn't deflect, simple as that. He's talking about different lever feel with the same calipers, and you're talking about different calipers with the same lever feel. Or something.
 

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bikeboy389 said:
He doesn't have it completely right, or at least isn't explaining it clearly, but the basis is correct as I understand such things. And your question isn't really about the same thing as what he's talking about.

When the brakes have a greater mechanical advantage, the lever will feel spongier. This sponginess is actually what it feels like to have some modulation in your braking--you have more levels of force available between "no brakes" and "full stop." When the brakes engage as soon as you touch the lever, you basically have all or none, with nothing between. This does not mean that your brakes will necessarily stop the bike better when your levers feel spongier, as Sheldon implies. What it means is that you will probably be able to apply more force to the brake pads at your maximum "squeeze," and you will also be able to more easily modulate your braking force, meaning you can use your brakes more effectively.

What you're asking is totally different. A crappy brake that's not rigid will not work as well as one that engages positively and doesn't deflect, simple as that. He's talking about different lever feel with the same calipers, and you're talking about different calipers with the same lever feel. Or something.
So he's using the word spongy where he should use the term modulation. Spongy is reserved for lever/caliper combos where you have to squeeze the levers to the bars to get full stop, no? To use correct terminology, the man's a buffoon.
 

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rogger said:
So he's using the word spongy where he should use the term modulation. Spongy is reserved for lever/caliper combos where you have to squeeze the levers to the bars to get full stop, no? To use correct terminology, the man's a buffoon.
Really the worst part is to look around his site and see how he completely Goof-ify's most of his bikes.
 

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rogger said:
So he's using the word spongy where he should use the term modulation. Spongy is reserved for lever/caliper combos where you have to squeeze the levers to the bars to get full stop, no? To use correct terminology, the man's a buffoon.
In the classical sense of buffoon, as in clown, yes. He's noisy and opinionated, and that makes him fun for a lot of people, annoying to others. But woe betide the man who thinks Sheldon Brown doesn't know what he's talking about most of the time. He's not a scientist, and his idea of precision can sometimes just be putting in words he doesn't understand, but his bike-fu is very strong.

He had it correct, and if he'd stuck with, "Your brakes will work better and be easier to modulate if you set them up so they're not right up against the rim," he'd have been just fine. He just fell down when he tried to explain the more complicated ideas behind it--I'm not sure I did that much better, except that I had his explanation to correct and expand on.

Oh, and I'd say that use of spongy to describe the feel of your levers when they're easy to modulate is probably correct. It's certainly the term that racers in other fields use--spongy isn't necessarily bad, but it IS what they feel like. When you're using crap brakes and you have to pull it to the max to stop, I believe the term is "sh*tty" or "knuckle-whitening" or "a$$ puckering" brakes.
 
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