Disc versus rim brakes
#2
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From: Santa Fe, NM
Bikes: Vassago Moosknuckle Ti 29+ XTR, 90's Merckx Corsa-01 9sp Record, PROJECT: 1954 Frejus SuperCorsa
My fair weather commuter has a set of Paul Racer Medium rim brakes, which are AMAZING. I love them.
My daily commuter has Avid BB7 with 180mm rotors, which I also love. After swapping several rotors due to unacceptable truing issues, I have found my Shimano XTR rotors to run perfectly true.
I like the mechanical Discs because they are extremely easy to work on, and once set up properly (also pretty simple) they work extremely well in all weather conditions. My brakes work equally well in wet or dry, and are much cleaner than their rim-based counterparts. If I didn't contend with frequent rain and snow, it would not matter as much to me, but I find I prefer the discs. Maintenance is easier, too, with the mechanical disc brakes, than with rim brakes. I also like the fact that I am not wearing my rims down. My disc-based wheels should outlast an equivalent set of conventional rim brake wheels given proper use and upkeep.
My wife's bike has a set of the Shimano Alfine hydraulic discs, which work very well but the added hydraulic aspect does not excite me. I've been reassured by those who know more about hydros that it is no big deal, and I'm sure I'll find out for myself whenever it will be time for me to work on them (I do all of my own wrenching).
My daily commuter has Avid BB7 with 180mm rotors, which I also love. After swapping several rotors due to unacceptable truing issues, I have found my Shimano XTR rotors to run perfectly true.
I like the mechanical Discs because they are extremely easy to work on, and once set up properly (also pretty simple) they work extremely well in all weather conditions. My brakes work equally well in wet or dry, and are much cleaner than their rim-based counterparts. If I didn't contend with frequent rain and snow, it would not matter as much to me, but I find I prefer the discs. Maintenance is easier, too, with the mechanical disc brakes, than with rim brakes. I also like the fact that I am not wearing my rims down. My disc-based wheels should outlast an equivalent set of conventional rim brake wheels given proper use and upkeep.
My wife's bike has a set of the Shimano Alfine hydraulic discs, which work very well but the added hydraulic aspect does not excite me. I've been reassured by those who know more about hydros that it is no big deal, and I'm sure I'll find out for myself whenever it will be time for me to work on them (I do all of my own wrenching).
#3
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From: PNW - Victoria, BC
Bikes: 2002 Litespeed Vortex - 2007 Trek Madone 5.9 - 2004 Redline Conquest Pro - Specialized S-Works Festina Team Model - 93 Cannondale M 800 Beast of the East
In the dry, no real difference except at time the discs will drag a bit. In the wet, discs work way better and the grit won't eat through your rims (this is especially true if you put in a lot of miles in the wet). My commuter/winter training bike has discs. All my other bikes have conventional brakes.
#5
Disc brake proponents often mention rim wear as a disadvantage of rim brakes. It's less often mentioned that winter weather conditions tend to add the element of grinding powder being continuously applied to your rims. Winter in these parts means eight months of continuous rain. Given that, I've decided that disc brakes are a must on at least one of my commuters.
I've got a V-brake with Travel Agent and Salmon Kool Stop pads on my Cross Check. For the most part, it stops very well in the rain, but I can hear it grinding the rims, and if I were going to use this setup regularly in the rain, I'd have to wipe down my rims at least daily, if not more, just to maintain some reasonable rim life.
Recently, I replaced the stock fork on my Kona Jake with a Civia Bryant fork, so now I've got a bike that weighs in at about 22 pounds (a bit lighter than my Cross Check) with a front disc brake (Avid BB7 road) and cantis in the rear:

Factor in the 700x28 Continental Grand Prix 4 Season tires, and this bike is as sporty on paved roads as anything I've got.
The "maintenance" on the disc brake consists of turning the barrel adjuster whenever the brake pads get a little worn and replacing the pads when their time comes. The power of these brakes, even with a 160mm rotor, is noticeably better than either V-brakes or well adjusted cantilevers. Having a canti in the rear was necessary since this frame doesn't have rear disc tabs, but frankly I don't think it makes much difference, being a rear brake.
The one complaint I have about this disc brake is that it squeals like Ned Beatty when I brake hard on a rainy day. On the other hand, I often want cars to notice my presence in that situation, so it's not all bad.
I have another bike that has Avid BB5 brakes. These are, in fact, a PITA. They don't brake nearly as well as the BB7's and the pad adjustment is significantly trickier.
I've got a V-brake with Travel Agent and Salmon Kool Stop pads on my Cross Check. For the most part, it stops very well in the rain, but I can hear it grinding the rims, and if I were going to use this setup regularly in the rain, I'd have to wipe down my rims at least daily, if not more, just to maintain some reasonable rim life.
Recently, I replaced the stock fork on my Kona Jake with a Civia Bryant fork, so now I've got a bike that weighs in at about 22 pounds (a bit lighter than my Cross Check) with a front disc brake (Avid BB7 road) and cantis in the rear:

Factor in the 700x28 Continental Grand Prix 4 Season tires, and this bike is as sporty on paved roads as anything I've got.
The "maintenance" on the disc brake consists of turning the barrel adjuster whenever the brake pads get a little worn and replacing the pads when their time comes. The power of these brakes, even with a 160mm rotor, is noticeably better than either V-brakes or well adjusted cantilevers. Having a canti in the rear was necessary since this frame doesn't have rear disc tabs, but frankly I don't think it makes much difference, being a rear brake.
The one complaint I have about this disc brake is that it squeals like Ned Beatty when I brake hard on a rainy day. On the other hand, I often want cars to notice my presence in that situation, so it's not all bad.
I have another bike that has Avid BB5 brakes. These are, in fact, a PITA. They don't brake nearly as well as the BB7's and the pad adjustment is significantly trickier.
#6
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From: Michigan
Bikes: Windsor Fens, Giant Seek 0 (2014, Alfine 8 + discs)
Avid BB7 up front, rim brakes on the back because my cheap Hybrid had disc tabs only in the front.
There's no comparison for riding in the winter; I've had the rim brakes simply do nothing when I squeezed them due to freezing rain on the rims. And even with Koolstop pads, different conditions result in slightly different braking power. With discs I know what I'll get when I squeeze the brake.
BTW I've been running cheap knockoff pads that I got for $6/set from eBay. They last a little longer than the Avid pads it came with, and the braking is the same. Avid pads are around $18 I think, I've never actually bought any after pricing them.
There's no comparison for riding in the winter; I've had the rim brakes simply do nothing when I squeezed them due to freezing rain on the rims. And even with Koolstop pads, different conditions result in slightly different braking power. With discs I know what I'll get when I squeeze the brake.
BTW I've been running cheap knockoff pads that I got for $6/set from eBay. They last a little longer than the Avid pads it came with, and the braking is the same. Avid pads are around $18 I think, I've never actually bought any after pricing them.
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#7
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Joined: Mar 2009
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From: Edmonton, Canada
This has been done many times. I've ridden, but never owned, a disc brake bike, so I tend to be a bit biased. While there are clear advantage to disc brakes, I'm of the opinion that these advantages are overstated. I've never had trouble stopping with rim brakes. Rain or winter, I can induce a skid, which means I've exceeded maximum braking power. (In fact, most of the extra grip offered by disc brakes is counteracted by the extra force they need to stop the wheel...what rim brakes lack in gripping power, they make up for in better leverage.)
I'm not sure how far you have to ride for rim wear to be an issue, but I apparently replace my wheels for other reasons before I hit it (if the spokes are corroded to the point where a complete rebuild is necessary, I take that as my cue to just replace the wheel).
Other than that, I have a general dislike of the look of discs, and the extra-beefy forks that are needed to deal with the forces involved. Plus, I'd need a new bike rack for my car, since my current setup can't fit a front disc brake.
The main advantage of discs that seems to be substantial enough to notice in real life is the easy setup, adjustment, and low pad wear. I will admit that fiddling with toe-in to keep my cantilevers from squeaking is a bit annoying. If that's a big deal to you, maybe discs are worth it.
I'm not sure how far you have to ride for rim wear to be an issue, but I apparently replace my wheels for other reasons before I hit it (if the spokes are corroded to the point where a complete rebuild is necessary, I take that as my cue to just replace the wheel).
Other than that, I have a general dislike of the look of discs, and the extra-beefy forks that are needed to deal with the forces involved. Plus, I'd need a new bike rack for my car, since my current setup can't fit a front disc brake.
The main advantage of discs that seems to be substantial enough to notice in real life is the easy setup, adjustment, and low pad wear. I will admit that fiddling with toe-in to keep my cantilevers from squeaking is a bit annoying. If that's a big deal to you, maybe discs are worth it.
Last edited by neil; 03-10-11 at 04:54 PM.
#8
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Joined: Jun 2010
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From: NW,Oregon Coast
Bikes: 8
Magura HS 33 is a great rim brake. they're on my trekking bike.
But on my touring bike, drop bars, I built years before, another Brake
Cantilever, was Scott-Peterson SE, has worked very well ..
Neither a snap to set up , but work great when you finish .
my foul weather bike has Drum Brakes , Sturmey Archer.
trouble and maintenance free.. they have worked well for 20 years.
But on my touring bike, drop bars, I built years before, another Brake
Cantilever, was Scott-Peterson SE, has worked very well ..
Neither a snap to set up , but work great when you finish .
my foul weather bike has Drum Brakes , Sturmey Archer.
trouble and maintenance free.. they have worked well for 20 years.
Last edited by fietsbob; 03-10-11 at 05:05 PM.
#9
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Joined: Feb 2009
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From: PNW - Victoria, BC
Bikes: 2002 Litespeed Vortex - 2007 Trek Madone 5.9 - 2004 Redline Conquest Pro - Specialized S-Works Festina Team Model - 93 Cannondale M 800 Beast of the East
I've had a rim fail due to excessive winter grinding, but I was doing a ton of miles for several winters in a row.
It was very scary when the rim let loose, I was descending doing about 45mph. Touched the brakes to set up for a turn; bam. Stayed upright, but very nearly soiled my shorts. I don't want to go through that again.
It was very scary when the rim let loose, I was descending doing about 45mph. Touched the brakes to set up for a turn; bam. Stayed upright, but very nearly soiled my shorts. I don't want to go through that again.
#10
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Joined: Nov 2007
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From: Santa Fe, NM
Bikes: Vassago Moosknuckle Ti 29+ XTR, 90's Merckx Corsa-01 9sp Record, PROJECT: 1954 Frejus SuperCorsa
I've had a rim fail due to excessive winter grinding, but I was doing a ton of miles for several winters in a row.
It was very scary when the rim let loose, I was descending doing about 45mph. Touched the brakes to set up for a turn; bam. Stayed upright, but very nearly soiled my shorts. I don't want to go through that again.
It was very scary when the rim let loose, I was descending doing about 45mph. Touched the brakes to set up for a turn; bam. Stayed upright, but very nearly soiled my shorts. I don't want to go through that again.
I've never had a failure (thank god), but have replaced several mountain bike rims over the years. I still recall the unmistakable sound that the gritty mud would make as the friction and grit gradually took the metal away on every hill. I think I got 3-4 years of heavy off road riding on wet trails out of my front rim. The rear lasted longer.
#11
You might as well have asked whether Jesus or Muhammed is better.
Discs when there's any chance of very wet roads, because my stopping power is consistent and only depends on my tires. I don't have to "wipe" the rims first by hitting the brakes a few times.
Discs when there's any chance of very wet roads, because my stopping power is consistent and only depends on my tires. I don't have to "wipe" the rims first by hitting the brakes a few times.
#12
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From: Mississauga/Toronto, Ontario canada
Bikes: I have 3 singlespeed/fixed gear bikes
I prefer Avid BB7's disc brakes. It's not so much about stopping power but rim wear is a serious problem in winter time, I ride a lot of miles and if I didn't have disc brakes I would be going through a lot of rims.Now I also have a fixed gear bike with rim brakes but rim wear is not an issue on a fixie , because I do most of my stopping through the drivetrain.
#14
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From: Rochester, NY
Bikes: 2010 Kona Dr. Dew, Moose Bicycle XXL (fat bike), Yuba Mundo V3
I've got lower-end Shimano hydraulic discs (M486s, I think). I love them. I specifically sought them out because I ride year round, and loss of brake power due to excessive ice/snow buildup on rim brakes is a significant concern. Even in nice weather, the control and power is excellent and noticeably better than rim brakes I've used (granted, I haven't used a lot, and most were relatively low-end). I've had them about a year, and haven't had to do any maintenance as yet either. By and large, They Just Work.
That said, occasionally during the worst part of the winter I did manage to get enough ice and snow buildup to degrade their performance. I could still stop, but there was a noticeable reduction in friction between the pads and the rotors.
I like them enough that I wish they existed for road bikes, and I'm putting a set on my Mundo cargo bike.
Don't get me wrong, for the majority (even vast majority) of riders V-brakes are going to be just fine. They will work well enough in most weather conditions. But if you want something that will stop you right freaking now no matter what the weather, and give you precise control of your breaking power, it's hard to beat hydraulic discs.
That said, occasionally during the worst part of the winter I did manage to get enough ice and snow buildup to degrade their performance. I could still stop, but there was a noticeable reduction in friction between the pads and the rotors.
I like them enough that I wish they existed for road bikes, and I'm putting a set on my Mundo cargo bike.

Don't get me wrong, for the majority (even vast majority) of riders V-brakes are going to be just fine. They will work well enough in most weather conditions. But if you want something that will stop you right freaking now no matter what the weather, and give you precise control of your breaking power, it's hard to beat hydraulic discs.
#15
Plays in traffic
Joined: May 2006
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From: Rochester, NY
Bikes: 1996 Litespeed Classic, 2006 Trek Portland, 2013 Ribble Winter/Audax, 2016 Giant Talon 4
Around Fort Collins, eh? There are additional considerations for disk brakes there--one pro, another con.
It's dead flat where I live, so I have little experience with descents, let alone high-speed and over the course of several miles. When I visited Fort Collins, I was glad I'd brought my disk brake bike. I rode the brakes a lot (due to my inexperience) descending from Estes Park down Devil's Gulch and through Glen Haven. They were very warm when we stopped for cinnamon buns in Glen Haven. I don't know what I'd have done to rim brakes using them the same way. (One of the locals I was riding with got a speeding ticket on his bike on the same descent. Your sheriff is something.)
The con is that the disk brakes make the wheels very heavy. The hubs are heavy, the rims are heavy, and the rotors also add to the mass you're spinning. I worked really hard to get the weight down on the wheels when I had a custom set made. They're still several hundred grams heavier than my heaviest (1609g) rim brake wheels. Climbing up to Estes Park was a real chore with those heavy wheels. Part of it was me too, as a lifelong low-lander and flat-lander, but one of my other bikes with lighter wheels would have been so much easier on that climb.
FWIW, when I return to Colorado, I'll be bringing a rim brake bike instead, probably the one with the 1400g wheelset.
It's dead flat where I live, so I have little experience with descents, let alone high-speed and over the course of several miles. When I visited Fort Collins, I was glad I'd brought my disk brake bike. I rode the brakes a lot (due to my inexperience) descending from Estes Park down Devil's Gulch and through Glen Haven. They were very warm when we stopped for cinnamon buns in Glen Haven. I don't know what I'd have done to rim brakes using them the same way. (One of the locals I was riding with got a speeding ticket on his bike on the same descent. Your sheriff is something.)
The con is that the disk brakes make the wheels very heavy. The hubs are heavy, the rims are heavy, and the rotors also add to the mass you're spinning. I worked really hard to get the weight down on the wheels when I had a custom set made. They're still several hundred grams heavier than my heaviest (1609g) rim brake wheels. Climbing up to Estes Park was a real chore with those heavy wheels. Part of it was me too, as a lifelong low-lander and flat-lander, but one of my other bikes with lighter wheels would have been so much easier on that climb.
FWIW, when I return to Colorado, I'll be bringing a rim brake bike instead, probably the one with the 1400g wheelset.
Last edited by tsl; 03-10-11 at 07:52 PM.
#16
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Joined: Nov 2008
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From: Bay Area, Calif.
I've been happy to stay with rim brakes for the conditions here. The limit on stopping power has always been due to the tires and bike geometry (i.e. avoid flipping) rather than the brakes. I have occasionally had to replace front rims due to brake wear, but it's been at over 50 kmiles of use so hasn't been too much of a concern. But we have a rather limited rainy season - those with more rain riding would see more rim wear.
So I haven't seen a reason to go with the slightly heavier, more expensive, and more complex disk brakes - YMMV.
So I haven't seen a reason to go with the slightly heavier, more expensive, and more complex disk brakes - YMMV.
#17
rebmeM roineS

Joined: Jan 2006
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From: Metro Indy, IN
Bikes: Bacchetta Giro A20, RANS V-Rex, RANS Screamer
One of my bikes, the V3, came with disc hubs and tabs on the fork and frame. How could I resist the urge to remove the V-brakes and slap on a pair of BB7's? They work great & require much less fiddling with than rim brakes.
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#18
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Joined: Aug 2009
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From: Burnaby, BC
I've been running rim brakes recently, after years with nothing but discs. They're adjusted really well, and I keep my rims very clean. I was just thinking the other day that they work really well, and maybe the extra weight of the discs wasn't really worth it.
Then I jumped on my Sutra (BB7s) for some errands...the first time I hit the brakes it was like I dropped a friggin anchor behind me. They are 100 times better. Maybe 200.
But...on my one bike weight matters - so I run the rim brakes.
Then I jumped on my Sutra (BB7s) for some errands...the first time I hit the brakes it was like I dropped a friggin anchor behind me. They are 100 times better. Maybe 200.
But...on my one bike weight matters - so I run the rim brakes.
#19
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Joined: Mar 2009
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From: Edmonton, Canada
I could buy grippier tires - though "better" isn't the word I'd use, since grippier usually involves other tradeoffs. Likewise, I could make adjustments to my riding technique, which would also increase stopping power.
But since I'm not a performance rider pushing things to the limit, these things don't hold much value to me. Maybe they do to you, and maybe that's the crowd that disc brakes have value for. But for most riders who are just out to get from point A to point B, the braking system isn't the restricting factor.
But since I'm not a performance rider pushing things to the limit, these things don't hold much value to me. Maybe they do to you, and maybe that's the crowd that disc brakes have value for. But for most riders who are just out to get from point A to point B, the braking system isn't the restricting factor.
#21
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Joined: Aug 2009
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From: Burnaby, BC
I could buy grippier tires - though "better" isn't the word I'd use, since grippier usually involves other tradeoffs. Likewise, I could make adjustments to my riding technique, which would also increase stopping power.
But since I'm not a performance rider pushing things to the limit, these things don't hold much value to me. Maybe they do to you, and maybe that's the crowd that disc brakes have value for. But for most riders who are just out to get from point A to point B, the braking system isn't the restricting factor.
But since I'm not a performance rider pushing things to the limit, these things don't hold much value to me. Maybe they do to you, and maybe that's the crowd that disc brakes have value for. But for most riders who are just out to get from point A to point B, the braking system isn't the restricting factor.
I think most riders, regardless of whether they're going from A to B or whatever, would prefer to do it in a safe fashion and maybe on a reliable bike.
But maybe not. Maybe some people enjoy the...er...nostalgia? Bikes with cantis do look kinda cool I guess.
Discs are also better in the dry. Sheesh.
#22
Mad bike riding scientist




Joined: Nov 2004
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From: Denver, CO
Bikes: Some silver ones, a red one, a black and orange one, and a few titanium ones
I have discs on a mountain bike, v-brakes on a mountain bike, cantilevers on a couple of road bikes and standard calipers on a road bike. They all stop the bikes. They all stop the bikes in the same distance. They are all capable of lifting the rear tire which is the ultimate test of stopping power of a set of brakes. Discs don't do anything better that the rim brakes.
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Stuart Black
Dreamin' of Bemidji Down the Mississippi (in part)
Plan Epsilon Around Lake Michigan in the era of Covid
Gold Fever Three days of dirt in Colorado
Pokin' around the Poconos A cold ride around Lake Erie
Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
#23
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Joined: Mar 2009
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From: Edmonton, Canada
There may be some people - those who ride down hills at 45mph, for instance - who operate outside of normal riding conditions and can benefit from disc brakes. Don't know, never tested it. But if you're barreling down hills at 45 mph, I don't think "safety" is your primary concern.
#25
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Joined: Feb 2009
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From: PNW - Victoria, BC
Bikes: 2002 Litespeed Vortex - 2007 Trek Madone 5.9 - 2004 Redline Conquest Pro - Specialized S-Works Festina Team Model - 93 Cannondale M 800 Beast of the East
Safety is a primary concern, but not the only one. You can descend at high speeds safely, but you have to have well maintained equipment and confidence in your skill set. In my case, I was lacking the former; fortunately the latter saved my bacon. This is now my commuter. The rims are pristine.

I got into competitive cycling at the ripe young age of 44. If you didn't learn to descend with speed and skill, you didn't get to the finish line with a chance at the podium very often. At the time my rim let go my commute included a 2 mile climb in the morning with about a 1/4 mile grade in excess of 12%. On the way home it was a lot more fun....... except when your rim explodes.
I got into competitive cycling at the ripe young age of 44. If you didn't learn to descend with speed and skill, you didn't get to the finish line with a chance at the podium very often. At the time my rim let go my commute included a 2 mile climb in the morning with about a 1/4 mile grade in excess of 12%. On the way home it was a lot more fun....... except when your rim explodes.
Last edited by Kojak; 03-11-11 at 01:12 AM.





