6 ms·

I think folks might be interested to consider some of the other myths and tests in the series, such as: * Titanium is ligther than steel * Fenders slow you do

I think folks might be interested to consider some of the other myths and tests in the series, such as: * Titanium is ligther than steel * Fenders slow you down * Stiffer frames are faster * Disc brakes work better than rim brakes * Higher tire pressure is faster * Bigger wheels roll faster https://www.renehersecycles.com/category/myths-in-cycling/ https://www.renehersecycles.com/category/myths-in-cycling/ For more nuanced tire testing and results, check out these two more recent articles * https://www.renehersecycles.com/how-we-test-tires/ https://www.renehersecycles.com/how-we-test-tires/ * https://www.renehersecycles.com/bq-tire-test-results/ https://www.renehersecycles.com/bq-tire-test-results/

alanbernstein 5y ago
These are interesting articles, but in https://www.renehersecycles.com/myth-12-disc-brakes-work-better-than-rim-brakes/ https://www.renehersecycles.com/myth-12-disc-brakes-work-bet..., it just says outright "Many rim brakes for wide tires are too weak to do this quickly, so in the rain, you end up with almost no braking power at all." It's not a myth, it's just conditionally true.
- masklinn 5y ago
  > It's not a myth, it's just conditionally true. Sounds to me like it’s generally true, and conditionally not: in good condition with thin tires on a metal wheel good rim brakes can be better than disc. Je general case is thus that you’re better off with disc as default.
  - jacquesm 5y ago
    We have a pretty wide collection of bikes, and all of them are in tiptop shape. None of the bikes with rim brakes have the same kind of stopping power as the disc versions. They don't even come close. Maybe there is an ideal bike somewhere that can outperform any of the disk brake systems that we have but if it exists I haven't seen it. Ever. Of course this is still 'anecdata' but I've seen a lot of bikes. The people that still seem to push for rimbrakes here in Europe are typically semi-pro or pro cyclists, who may or may not have valid concerns regarding injury due to the disc edges being too sharp (they are now usually chamfered to allay this).
    - nikau 5y ago
      The difference is the modulation, especially with hydro discs. Rim brakes are like drum brakes on cars, they are more binary with not enough braking power that then snap transitions to locking up. hydro disc brakes let you brake hard and avoid lockups.
    - masklinn 5y ago
      > None of the bikes with rim brakes have the same kind of stopping power as the disc versions. Yes I expect the people who say that rim brakes are better don’t mean "have better stopping powder" as that seems unlikely, but rather "have sufficient stopping power while being lighter / more flexible / …".
    - jmilloy 5y ago
      I haven't had issues with any of my disc brakes overheating, but that sounds like one reason to prefer rim brakes, rim brakes cool better. That's not an issue for a lot of situations, though.
- Xylakant 5y ago
  You should also keep in mind that the articles are slightly dated, so technical improvements may have changed the equation. For example in the comments thread for the disc brake article, people mention that they cannot find disc rotors with sufficient size for tandems. With the rise of cargo and electric bikes, disc brakes with pretty massive stopping power have come to market. Mine can safely stop the bike, me, plus 100kg of extra load for a total of about 250kg [1], the R+M Load Cargo has an S-Pedelec version with a powered top speed of 45km/h. Those brakes will work for any tandem as well. [1] yes, I tried.
  - jacquesm 5y ago
    On tandems the problem hasn't been stopping power for years (every since we had hydraulic brakes this has been a solved problem). The bigger issue on a tandem is that when you're going downhill you will end up overheating your brake, whatever kind of system you are using. There is just too much kinetic energy to get rid of as heat for your normal brake system to be able to deal with.
    - Xylakant 5y ago
      The kinetic energy depends on weight and speed. Cargo bikes easily come into that range, especially the fast 45km/h electric ones. Energy dissipation depends on the size of the rotor and sizes have been increasing substantially. When I bought mine, the standard disk size was 160mm, I opted for the upgrade to 180mm. The current generation of Riese-Müller Load uses dedicated cargo bike brakes with thicker rotors (2.3mm instead of 1.8) and a 223mm diameter on the rear wheel, 160mm on the front. Those brakes have substantially more staying power before they fade. Edit: Generally, developments for cargo bikes seem to help tandems and tandem developments benefit cargo bikes. There's now an option to use the tandem version of the Rohloff internal geared hub for RM cargo bikes. That's a serious upgrade to all previous internal hubs, especially since you can combine it with a belt drive. It's a tiny bit expensive, though...
      - jacquesm 5y ago
        Yes, that Rohloff stuff is nice, and indeed a tiny bit expensive.
- twic 5y ago
  This article doesn't have measurements, or references to measurements. It's just someone's opinions. Cycling already has plenty of those, thanks.
theelous3 5y ago
> Disc brakes work better than rim brakes They really do though. Hydraulic disk breaks have way more stopping power, higher resistance to wet and dirt, don't weaken with each use, and are both lower maintenance in the long and short term, and easier to service and get correct. It's not out of ignorance the bike uses who need brakes the most 100% use disks (mountain biking). The argument made is that "rim breaks are disk brakes". This is true in the same sense that topologically humans are donut shaped. It ignores all subtilty. Wheels flex in turns where your disks do not, etc etc forever.
- jacquesm 5y ago
  And calipers on disc brakes have a lot more grip on the disc than the rubber brake shoes on rim brakes, which - especially when wet - can be quite useless.
- jmilloy 5y ago
  I think the myth is "all disc brakes are always better than all rim brakes". There are definitely reasons it y situations to prefer disc brakes, especially hydraulic, but also reasons to prefer rim brakes.
  - theelous3 5y ago
    > but also reasons to prefer rim brakes Like? I honestly can't think of any. They don't save enough on weight to be worth the hassle for all but the tour de france. They don't improve areo. Why?
consp 5y ago
> * Higher tire pressure is faster For semi-professionals sure this is a myth for normal road surfaces, but for every day use by normal people with no knowledge whatsoever putting just over 2 bar in their wheels since that is what their cars use you definitely win efficiency, al lot.
- laputan_machine 5y ago
  If I used 32psi in my bicycle tyres I'd be getting pinch flats all the time! I run 35x700c marathon plus', which requires a minimum of 65psi [4 bar] (https://www.schwalbe.com/en/tour-reader/marathon-plus https://www.schwalbe.com/en/tour-reader/marathon-plus) Maybe for mountain bike tyres that advice works well.
  - jmilloy 5y ago
    I use 30psi on my 35mm and 44mm tires on paved and unpaved surfaces all the time. Have you tried, with a good supple tire? Mine have a max of 65psi!

alanbernstein 5y ago

These are interesting articles, but in https://www.renehersecycles.com/myth-12-disc-brakes-work-better-than-rim-brakes/ https://www.renehersecycles.com/myth-12-disc-brakes-work-bet..., it just says outright "Many rim brakes for wide tires are too weak to do this quickly, so in the rain, you end up with almost no braking power at all." It's not a myth, it's just conditionally true.

masklinn 5y ago
> It's not a myth, it's just conditionally true. Sounds to me like it’s generally true, and conditionally not: in good condition with thin tires on a metal wheel good rim brakes can be better than disc. Je general case is thus that you’re better off with disc as default.
- jacquesm 5y ago
  We have a pretty wide collection of bikes, and all of them are in tiptop shape. None of the bikes with rim brakes have the same kind of stopping power as the disc versions. They don't even come close. Maybe there is an ideal bike somewhere that can outperform any of the disk brake systems that we have but if it exists I haven't seen it. Ever. Of course this is still 'anecdata' but I've seen a lot of bikes. The people that still seem to push for rimbrakes here in Europe are typically semi-pro or pro cyclists, who may or may not have valid concerns regarding injury due to the disc edges being too sharp (they are now usually chamfered to allay this).
  - nikau 5y ago
    The difference is the modulation, especially with hydro discs. Rim brakes are like drum brakes on cars, they are more binary with not enough braking power that then snap transitions to locking up. hydro disc brakes let you brake hard and avoid lockups.
  - masklinn 5y ago
    > None of the bikes with rim brakes have the same kind of stopping power as the disc versions. Yes I expect the people who say that rim brakes are better don’t mean "have better stopping powder" as that seems unlikely, but rather "have sufficient stopping power while being lighter / more flexible / …".
  - jmilloy 5y ago
    I haven't had issues with any of my disc brakes overheating, but that sounds like one reason to prefer rim brakes, rim brakes cool better. That's not an issue for a lot of situations, though.
Xylakant 5y ago
You should also keep in mind that the articles are slightly dated, so technical improvements may have changed the equation. For example in the comments thread for the disc brake article, people mention that they cannot find disc rotors with sufficient size for tandems. With the rise of cargo and electric bikes, disc brakes with pretty massive stopping power have come to market. Mine can safely stop the bike, me, plus 100kg of extra load for a total of about 250kg [1], the R+M Load Cargo has an S-Pedelec version with a powered top speed of 45km/h. Those brakes will work for any tandem as well. [1] yes, I tried.
- jacquesm 5y ago
  On tandems the problem hasn't been stopping power for years (every since we had hydraulic brakes this has been a solved problem). The bigger issue on a tandem is that when you're going downhill you will end up overheating your brake, whatever kind of system you are using. There is just too much kinetic energy to get rid of as heat for your normal brake system to be able to deal with.
  - Xylakant 5y ago
    The kinetic energy depends on weight and speed. Cargo bikes easily come into that range, especially the fast 45km/h electric ones. Energy dissipation depends on the size of the rotor and sizes have been increasing substantially. When I bought mine, the standard disk size was 160mm, I opted for the upgrade to 180mm. The current generation of Riese-Müller Load uses dedicated cargo bike brakes with thicker rotors (2.3mm instead of 1.8) and a 223mm diameter on the rear wheel, 160mm on the front. Those brakes have substantially more staying power before they fade. Edit: Generally, developments for cargo bikes seem to help tandems and tandem developments benefit cargo bikes. There's now an option to use the tandem version of the Rohloff internal geared hub for RM cargo bikes. That's a serious upgrade to all previous internal hubs, especially since you can combine it with a belt drive. It's a tiny bit expensive, though...
    - jacquesm 5y ago
      Yes, that Rohloff stuff is nice, and indeed a tiny bit expensive.
twic 5y ago
This article doesn't have measurements, or references to measurements. It's just someone's opinions. Cycling already has plenty of those, thanks.

theelous3 5y ago

> Disc brakes work better than rim brakes They really do though. Hydraulic disk breaks have way more stopping power, higher resistance to wet and dirt, don't weaken with each use, and are both lower maintenance in the long and short term, and easier to service and get correct. It's not out of ignorance the bike uses who need brakes the most 100% use disks (mountain biking). The argument made is that "rim breaks are disk brakes". This is true in the same sense that topologically humans are donut shaped. It ignores all subtilty. Wheels flex in turns where your disks do not, etc etc forever.

jacquesm 5y ago
And calipers on disc brakes have a lot more grip on the disc than the rubber brake shoes on rim brakes, which - especially when wet - can be quite useless.
jmilloy 5y ago
I think the myth is "all disc brakes are always better than all rim brakes". There are definitely reasons it y situations to prefer disc brakes, especially hydraulic, but also reasons to prefer rim brakes.
- theelous3 5y ago
  > but also reasons to prefer rim brakes Like? I honestly can't think of any. They don't save enough on weight to be worth the hassle for all but the tour de france. They don't improve areo. Why?

consp 5y ago

> * Higher tire pressure is faster For semi-professionals sure this is a myth for normal road surfaces, but for every day use by normal people with no knowledge whatsoever putting just over 2 bar in their wheels since that is what their cars use you definitely win efficiency, al lot.

laputan_machine 5y ago
If I used 32psi in my bicycle tyres I'd be getting pinch flats all the time! I run 35x700c marathon plus', which requires a minimum of 65psi [4 bar] (https://www.schwalbe.com/en/tour-reader/marathon-plus https://www.schwalbe.com/en/tour-reader/marathon-plus) Maybe for mountain bike tyres that advice works well.
- jmilloy 5y ago
  I use 30psi on my 35mm and 44mm tires on paved and unpaved surfaces all the time. Have you tried, with a good supple tire? Mine have a max of 65psi!