One Man’s View Of Disc Brakes
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#103
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The question as to the relative merits of disc beakes vs. pointy beakes is best answered by comparing two representative species: the spoonbill stork (disc beake) and the heron (pointy beake). In each case the beake performs the same primary function: food gathering.
The question is: which is more efficient? Will spoonbills eventually abandon their disc beakes in favour of pointy beakes, or will a bird like the Blue Heron eventually adopt disc beakes? Of course we won't know the answer for millenia, but a significant question it remains.
The spoonbill stork (genus platalea; various species), as we all know, has a beake that is well adapted to performing well in wet conditions (shallow, muddy waters), where it uses its 'spoon' first to muddy the waters, so to speak, and then to filter out, trap, and consume the tiny creatures it stirs up.
Now, the great blue heron (Ardea herodias) is of course a bird of a very different feather. Its primary diet consists of fish, frogs, small mammals and the like which it commonly spears with its pointy beake and then swallows.
What, then, can we infer from the rather obvious continued survival of the two about the relative merits of disc vs. pointy beakes? Well, it is not unreasonable to suggest that each is well-adapted to its primary function: to obtain food.
That said, ornithological debates on interwebz discussion forums suggest that enthusiasts will not rest content until one side or the other 'winz', with either Disc Beakeists or Pointy Beakeists emerging triumphant.
The question is: which is more efficient? Will spoonbills eventually abandon their disc beakes in favour of pointy beakes, or will a bird like the Blue Heron eventually adopt disc beakes? Of course we won't know the answer for millenia, but a significant question it remains.
The spoonbill stork (genus platalea; various species), as we all know, has a beake that is well adapted to performing well in wet conditions (shallow, muddy waters), where it uses its 'spoon' first to muddy the waters, so to speak, and then to filter out, trap, and consume the tiny creatures it stirs up.
Now, the great blue heron (Ardea herodias) is of course a bird of a very different feather. Its primary diet consists of fish, frogs, small mammals and the like which it commonly spears with its pointy beake and then swallows.
What, then, can we infer from the rather obvious continued survival of the two about the relative merits of disc vs. pointy beakes? Well, it is not unreasonable to suggest that each is well-adapted to its primary function: to obtain food.
That said, ornithological debates on interwebz discussion forums suggest that enthusiasts will not rest content until one side or the other 'winz', with either Disc Beakeists or Pointy Beakeists emerging triumphant.
Last edited by badger1; 08-21-19 at 03:46 PM.
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#104
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The question as to the relative merits of disc beakes vs. pointy beakes is best answered by comparing two representative species: the spoonbill stork (disc beake) and the heron (pointy beake). In each case the beake performs the same primary function: food gathering.
The question is: which is more efficient? Will spoonbills eventually abandon their disc beakes in favour of pointy beakes, or will a bird like the Blue Heron eventually adopt disc beakes? Of course we won't know the answer for millenia, but a significant question it remains.
The spoonbill stork (genus platalea; various species), as we all know, has a beake that is well adapted to performing well in wet conditions (shallow, muddy waters), where it uses its 'spoon' first to muddy the waters, so to speak, and then to filter out, trap, and consume the tiny creatures it stirs up.
Now, the great blue heron (Ardea herodias) is of course a bird of a very different feather. Its primary diet consists of fish, frogs, small mammals and the like which it commonly spears with its pointy beake and then swallows.
What, then, can we infer from the rather obvious continued survival of the two about the relative merits of disc vs. pointy beakes? Well, it is not unreasonable to suggest that each is well-adapted to its primary function: to obtain food.
That said, ornithological debates on interwebz discussion forums suggests that enthusiasts will not rest content until one side or the other 'winz', with either Disc Beakeists or Pointy Beakeists emerging triumphant.
The question is: which is more efficient? Will spoonbills eventually abandon their disc beakes in favour of pointy beakes, or will a bird like the Blue Heron eventually adopt disc beakes? Of course we won't know the answer for millenia, but a significant question it remains.
The spoonbill stork (genus platalea; various species), as we all know, has a beake that is well adapted to performing well in wet conditions (shallow, muddy waters), where it uses its 'spoon' first to muddy the waters, so to speak, and then to filter out, trap, and consume the tiny creatures it stirs up.
Now, the great blue heron (Ardea herodias) is of course a bird of a very different feather. Its primary diet consists of fish, frogs, small mammals and the like which it commonly spears with its pointy beake and then swallows.
What, then, can we infer from the rather obvious continued survival of the two about the relative merits of disc vs. pointy beakes? Well, it is not unreasonable to suggest that each is well-adapted to its primary function: to obtain food.
That said, ornithological debates on interwebz discussion forums suggests that enthusiasts will not rest content until one side or the other 'winz', with either Disc Beakeists or Pointy Beakeists emerging triumphant.
#105
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I had a squeal a couple weeks ago; my rotor was evidently contaminated while sending a wheel off to be rebuilt. It was a matter of minutes to pull the wheel, wipe the rotor, pull the pads and sand them on a diamond plate (though a piece of sand paper on a kitchen counter would work just as well), and re-install. The process was certainly no worse than cleaning metal shards out of rim brake pads.
Why not replace the caliper with the same model - not available?
Why not replace the caliper with the same model - not available?
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I had a squeal a couple weeks ago; my rotor was evidently contaminated while sending a wheel off to be rebuilt. It was a matter of minutes to pull the wheel, wipe the rotor, pull the pads and sand them on a diamond plate (though a piece of sand paper on a kitchen counter would work just as well), and re-install. The process was certainly no worse than cleaning metal shards out of rim brake pads.
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#108
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I don’t sand pads; I cook them in a gas flame for 20-30 seconds. Ten with a propane torch would do. It has never failed for me.
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Hey, if you like Discs - here is a new pair. https://www.bikeforums.net/21084590-post1.html
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i think my view of disc brakes is that they seem cool but i won't get them because the bikes that don't have them are cheaper
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I'm surprised there are people trying to say discs are easier to maintain or it's on par...
IME, it's extremely rare to find a problem in a rim brake system that's hard to solve, and there's no way I could say that about discs.
Pads rubbing? True the disc... Still rubbing. Maybe it's the caliper? Oh look, someone shattered one of the ceramic pistons, there we go. New caliper. Oh wait, still rubbing. Hey, I guess the piston was damaged by someone trying to force the caliper open further than it goes, because it can't be adjusted not to rub, because the frame company couldn't be bothered ensuring the mount was square. Which I can't fix properly, because my boss is too much of a tightarse to buy the tool for it. What fun.
Rotor squealing? Clean it, clean the pads. Still squealing? Replace the pads, clean the rotor again. Still squealing? Damn, the rotor is contaminated. New rotor, clean the pads. OMG, still squealing, because it's basically a result of the geometry of the system and you've gotta just cross your fingers it isn't plagued by squeals. Yay.
Then there's bleeding... Anyone run into mysterious dramas with that bloody palaver? What joy. Oh, and have fun catching the cancer from SRAM systems.
But hey, if you wear out rims from riding in the muck, maybe the potential hassle is worth it. Don't get me wrong, many disc bikes are hassle free, but if one decides to give you a hard time... Much potential.
IME, it's extremely rare to find a problem in a rim brake system that's hard to solve, and there's no way I could say that about discs.
Pads rubbing? True the disc... Still rubbing. Maybe it's the caliper? Oh look, someone shattered one of the ceramic pistons, there we go. New caliper. Oh wait, still rubbing. Hey, I guess the piston was damaged by someone trying to force the caliper open further than it goes, because it can't be adjusted not to rub, because the frame company couldn't be bothered ensuring the mount was square. Which I can't fix properly, because my boss is too much of a tightarse to buy the tool for it. What fun.
Rotor squealing? Clean it, clean the pads. Still squealing? Replace the pads, clean the rotor again. Still squealing? Damn, the rotor is contaminated. New rotor, clean the pads. OMG, still squealing, because it's basically a result of the geometry of the system and you've gotta just cross your fingers it isn't plagued by squeals. Yay.
Then there's bleeding... Anyone run into mysterious dramas with that bloody palaver? What joy. Oh, and have fun catching the cancer from SRAM systems.
But hey, if you wear out rims from riding in the muck, maybe the potential hassle is worth it. Don't get me wrong, many disc bikes are hassle free, but if one decides to give you a hard time... Much potential.
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Last edited by Kimmo; 08-21-19 at 04:16 PM.
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#112
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I'm surprised there are people trying to say discs are easier to maintain or it's on par...
IME, it's extremely rare to find a problem in a rim brake system that's hard to solve, and there's no way I could say that about discs.
Pads rubbing? True the disc... Still rubbing. Maybe it's the caliper? Oh look, someone shattered one of the ceramic pistons, there we go. New caliper. Oh wait, still rubbing. Hey, I guess the piston was damaged by someone trying to force the caliper open further than it goes, because it can't be adjusted not to rub, because the frame company couldn't be bothered ensuring the mount was square. Which I can't fix properly, because my boss is too much of a tightarse to buy the tool for it. What fun.
Rotor squealing? Clean it, clean the pads. Still squealing? Replace the pads, clean the rotor again. Still squealing? Damn, the rotor is contaminated. New rotor, clean the pads. OMG, still squealing, because it's basically a result of the geometry of the system and you've gotta just cross your fingers it isn't plagued by squeals. Yay.
Then there's bleeding... Anyone run into mysterious dramas with that bloody palaver? What joy. Oh, and have fun catching the cancer from SRAM systems.
But hey, if you wear out rims from riding in the muck, maybe the potential hassle is worth it. Don't get me wrong, many disc bikes are hassle free, but if one decides to give you a hard time... Much potential.
IME, it's extremely rare to find a problem in a rim brake system that's hard to solve, and there's no way I could say that about discs.
Pads rubbing? True the disc... Still rubbing. Maybe it's the caliper? Oh look, someone shattered one of the ceramic pistons, there we go. New caliper. Oh wait, still rubbing. Hey, I guess the piston was damaged by someone trying to force the caliper open further than it goes, because it can't be adjusted not to rub, because the frame company couldn't be bothered ensuring the mount was square. Which I can't fix properly, because my boss is too much of a tightarse to buy the tool for it. What fun.
Rotor squealing? Clean it, clean the pads. Still squealing? Replace the pads, clean the rotor again. Still squealing? Damn, the rotor is contaminated. New rotor, clean the pads. OMG, still squealing, because it's basically a result of the geometry of the system and you've gotta just cross your fingers it isn't plagued by squeals. Yay.
Then there's bleeding... Anyone run into mysterious dramas with that bloody palaver? What joy. Oh, and have fun catching the cancer from SRAM systems.
But hey, if you wear out rims from riding in the muck, maybe the potential hassle is worth it. Don't get me wrong, many disc bikes are hassle free, but if one decides to give you a hard time... Much potential.
#Disappointed
Last edited by noodle soup; 08-21-19 at 05:00 PM.
#113
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Care to fill me in?
...Are you saying my basic premise, that discs can be way more of a PITA, is incorrect? Or was it something else?
...Are you saying my basic premise, that discs can be way more of a PITA, is incorrect? Or was it something else?
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Half-step triple, using double gear ~~~ 6400 STI rebuild walkthrough ~~~ Want 8/9/10s @126mm OLD? OCR. ~~~ Shimano cassette body overhaul ~~~ Ergopower Escape wear repair ~~~ PSA: drivetrain wear
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Last edited by Kimmo; 08-21-19 at 05:40 PM.
#114
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Putting the subject aside, the guy's a total wanker.
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Not really? If the bike is maintained properly on a regular basis by either a competent mechanic or a home mechanic it requires very little work. Clean the caliper of build up, push the pistons in and out a few times each and wipe them down to make sure they aren't sticking, occasionally true a rotor or use icetech rotors that almost never go out of true. Contamination isn't really that big of a concern, and bleeding is a simple process that takes like 2x to get the hang of. For shimano you can go like 3-4 years even without a bleed as the mineral oil doesn't absorb water. Overall if you include total time over the life of a rim brake bike that used in the rain, the time spent works closer than you'd expect if you factor in a relace of a rim hoop that involves tensioning and/or replacing spokes.
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#116
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I got confused and thought this was the tubular thread.
I have discs on the MTBs, and the cxes, mostly rim on everything else and tandem is rim front, disc rear.
To the tandem. I put a TRP hybrid on there and it is very smooth. I like PowerCordz vs steel cable feel, but the brake is a good option.
I also went with a 160mm rotor from PowerTap and it had something very big before.
I also have the rotor farther from the seat stays/mount as I am neutrally dished on a narrower hub. Spacing is 145mm wide, too wide IMO, but I bought the bike used.
So anyway...
On hard (HARD) stopping now, there is deformation. Maybe the seat stays flex, maybe as the mounts are farther they flex. That takes the brake out of alignment during braking. Of course rim brakes move too and they will rid up the brake track. But I could always (dry road conditions) stand the tandem on the front wheel with rim brakes before the new ENVE serrated things. I don't much care, as I rarely brake, but if stopping hard were important I'd go back to smooth tubular rims and rim brakes. As is, I very much like the rear disc as a drag brake. When I need to stop fast, I use the front and although not as good as a smooth sided rim, it works.
I don't ride in the rain.
I have discs on the MTBs, and the cxes, mostly rim on everything else and tandem is rim front, disc rear.
To the tandem. I put a TRP hybrid on there and it is very smooth. I like PowerCordz vs steel cable feel, but the brake is a good option.
I also went with a 160mm rotor from PowerTap and it had something very big before.
I also have the rotor farther from the seat stays/mount as I am neutrally dished on a narrower hub. Spacing is 145mm wide, too wide IMO, but I bought the bike used.
So anyway...
On hard (HARD) stopping now, there is deformation. Maybe the seat stays flex, maybe as the mounts are farther they flex. That takes the brake out of alignment during braking. Of course rim brakes move too and they will rid up the brake track. But I could always (dry road conditions) stand the tandem on the front wheel with rim brakes before the new ENVE serrated things. I don't much care, as I rarely brake, but if stopping hard were important I'd go back to smooth tubular rims and rim brakes. As is, I very much like the rear disc as a drag brake. When I need to stop fast, I use the front and although not as good as a smooth sided rim, it works.
I don't ride in the rain.
#117
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I'm not saying they are a PITA, I'm saying they can be. They can **** you up the wall way harder than any cable rim brake system, if you're unlucky. Part of it is because hydraulics, and part of it is because disc, particularly the problem of squealing which is can be time-consuming and sometimes futile to address.
Most folks won't have issues, but as a mechanic I saw the bikes that had them. Usually a simple fix, but the scope for complications is huge.
Most folks won't have issues, but as a mechanic I saw the bikes that had them. Usually a simple fix, but the scope for complications is huge.
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Half-step triple, using double gear ~~~ 6400 STI rebuild walkthrough ~~~ Want 8/9/10s @126mm OLD? OCR. ~~~ Shimano cassette body overhaul ~~~ Ergopower Escape wear repair ~~~ PSA: drivetrain wear
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Sheldon Brown's bike info ~~~ Park Tools repair help
Half-step triple, using double gear ~~~ 6400 STI rebuild walkthrough ~~~ Want 8/9/10s @126mm OLD? OCR. ~~~ Shimano cassette body overhaul ~~~ Ergopower Escape wear repair ~~~ PSA: drivetrain wear
List of US/Canada bike co-ops ~~~ Global list
#118
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I've never had hydraulic disks, but it has always been my suspicion that they would be just as susceptible to incessant squealing as my mechanical disks since I hear them squealing all the time when I ride with guys who have them. I think some people either don't notice or it doesn't bother them. Thanks for clearing that up.
#119
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I've never had hydraulic disks, but it has always been my suspicion that they would be just as susceptible to incessant squealing as my mechanical disks since I hear them squealing all the time when I ride with guys who have them. I think some people either don't notice or it doesn't bother them. Thanks for clearing that up.
We just live with it, pretend it doesn't actually happen and hope nobody complains.
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Speaking of squeal - I have fond memories of Mafac Racers in the days when we used the Mafac pads. You had some control of squeal on setup. I loved it when the squeal was acceptable for routine stops, but loud for really hard ones. Great tool for riding in Boston. When a driver pulls a typical Boston stunt, I'd hit the front brake extra hard. Every head within a block would turn. I'd point at the car. Every eye would follow my point. The squeal brings the driver out of his stupor. He looks up and finds everybody looking at him. Driver slinks off like a guilty dog that's been caught. Fun.
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#122
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Yeah, if the squeal is optional, it's more of a feature than a bug.
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Sheldon Brown's bike info ~~~ Park Tools repair help
Half-step triple, using double gear ~~~ 6400 STI rebuild walkthrough ~~~ Want 8/9/10s @126mm OLD? OCR. ~~~ Shimano cassette body overhaul ~~~ Ergopower Escape wear repair ~~~ PSA: drivetrain wear
List of US/Canada bike co-ops ~~~ Global list
Sheldon Brown's bike info ~~~ Park Tools repair help
Half-step triple, using double gear ~~~ 6400 STI rebuild walkthrough ~~~ Want 8/9/10s @126mm OLD? OCR. ~~~ Shimano cassette body overhaul ~~~ Ergopower Escape wear repair ~~~ PSA: drivetrain wear
List of US/Canada bike co-ops ~~~ Global list