More disc brake vs. rim brake controversy.
 

GCN tested it again.


Conclusions?

In the dry, rim brakes (on carbon rims nonetheless) were marginally faster due to better aero (higher top speed between curves.)

In the wet, disc brakes were better... obviously.

My personal conclusions.

Do you ride in the rain at the edge of grip on carbon rims?

If the answer is yes, then disc brakes could be good for you.

If the answer is (likely) no, rim brakes are actually better for you.

I'd love to see the same test done with aluminum rims (or at least aluminum brake tracks), although I bet the aero or weight penalty would affect the results more.

Someone once asked "why disc brakes aren't on road bikes".

I think the answer is pretty clearly "they barely do crap for normal riding, and most people don't ride in situations where they're useful."

Come on, be honest, when's the last time you purposefully rode in the rain?

Using the argument of "I like disc brakes because occasionally I get caught in the rain" is the same as saying "I put snow tires on my summer convertible car because occasionally we'll have a freak snow storm and I'll get caught in it." (Happens more often than you think here in Bozeman.)

The main advantage (to me) of disc brakes is they easily allow much wider tires.

Last week. Mix of pavement and mud/gravel


Not all of those on BF are fair-weather riders riding only when it is 70F and sunny on pavement with flat roads and only a seat wedge and a bidon.

If you riding live such a sheltered riding life, I'd advise trying rain sometime. It can be quite fun TBH.

Everyone tries to make this a personal thing ... Obviously each of us needs to make a personal choice ... on Everything.

The controversy here has been whether discs are 'better" In General.

And this latest video just highlights what all the honest folk already new.

I think that's much more of an issue of "trying to use the bike for something it wasn't designed for" rather than disc vs. rim. Rim brakes can be made to accommodate any size tire, you just need to bike to be designed around accommodating that tire size.

I do ride in the rain. It's hot as hell here in Bozeman at the moment, rain gives me a reprieve.

However, what I DON'T do is RACE around in the rain. I take it a bit slower. I don't push my tires to their grip limit in the rain. My rim brakes work PERFECTLY well in that situation.

The other issue is this.

It's well known that rim brakes are more aero than disc brakes.

So let's compare the amount of time you spend taking advantage of aero advantages vs time spent braking.

Oh it's probably something like 90%-10%. Honestly probably closer to 98% 2%. I'd imagine over a longer course, the aero advantage of rim brakes would shine.

While I agree, to me it stems from the whole "fake news" debacle. People like to tout disc brakes like they're the "be-all-end-all" braking solution for bicycles. When in reality, they're not. They're really only useful in situations where most people don't even ride, and EVEN THEN the difference is marginal. 8 seconds over 5k downhill with lots of sharp curves? I can almost guarantee you those 8 seconds will be made up in aero gains from the rim brakes in the resulting flat section.

I mean geeze, how many of you have a road with 11 serious curves which require heavy braking in 5k? I'd imagine the number is probably around 2%... maybe. The "biggest" hill within 20 miles of me requires me to brake for exactly ONE turn. And that's with 1200 feet of descent.

Then use them. Clearly you're stuck in your ways-and looking for reasons not to change.

But IMHO IME good discs are just better than good rim brakes. More power, more modulation. They're just better. My Di2 Bigfoot with Shimano hydros brakes better any time than my Seven Chorus 11s with Campag skeletons....The Seven is going to stay around for a long time because it is a nice frameset. But, when it comes time to retire it-it'll be a disc brake bike.


Windows 3.1 had some neat stuff about it. Win95 was a mess, but did lots of stuff Win3 and DOS didn't....but WinNT was better. WinXP after SP1 was better than that....Win7 was better than that. They're computers and bike parts, not religions.

I thought we already settled this argument? The marketing gurus in the cycling industry are responsible for stirring this pot. It's genius, really.

They're computers, NOT bike parts. Software that's developed for them keep getting more complex and thus require more processing power, more memory, more robust OS, etc. How has cycling changed in the last, oh say, 50 years, where you need disc brakes or your bike becomes obsolete?

Don't get me wrong. I like disc brakes, especially in the wet and snow, and yes, I commute year round in the craziest conditions, but they are not indispensable. Studded tires are and fenders are more important to me in the winter than disc brakes.

I mean really, we should still be just fine with steel rims and Campag Delta brakes. Hell, the Strong Men of the TdF used to climb those mountains with a single-speed.

Other than weight reduction from the materials that are used in today's bikes, which, yes, is huge, principally the bikes hasn't changed much in decades, and we know that cycling is all about the engine anyway, don't we?;)

I can still ride a century with my 1985 21-lb steel road bike just as fast as I could with my 16-lb carbon bike. My Windows 3.1 machine, if I had one, could do what with today's software?

My neighborhood has residential streets of such grade that it is entirely possible to reach +50mph while descending them. You don't need the brakes for the curves-- the brakes are needed because there are stop signs at the bottoms of the hills, and the cross traffic doesn't stop.

And sure, rim brakes generally work absolutely well enough-- and they have for decades. But I like my disc brakes. I like them as much as I dislike people yelling at the top of their lungs that disc brakes are "unnecessary." As with virtually everything else in the world, two things can exist without one being inherently superior or inferior to one another. Coke and Pepsi manage to coexist. Why can't disc brakes be our Coke and Pepsi? I mean, we'll always have frame material, chain lube, tire width, etc, to argue about ad infinitum.

Jaw dropping fun fact....Most ATMs are still running embedded Windows XP... :eek:

I had no idea. Should I be worried when take out cash?:)

Disc brakes on carbon rims would make sense for eliminating wear on the brake track. But if you go with carbon rims would the weight savings be negated by the extra weight of the disc setup?:foo:

Being a fair-weather cyclist, I'm good with rim brakes. I can, however, remember one decent in the past year where I thought it "might" be nice to have disc brakes. I don't know.
I sort of like the idea of disc brakes, but don't think they're really necessary - at least for the type of riding I do. But that won't stop me from using the "but I need a bike with disc brakes" excuse when I get the itch to get another bike. :lol:

Most of my rides are commutes. Weight and aero aren't big concerns.
I like that (hydro) discs need less hand effort for the same amount of braking.
I thoroughly appreciate that discs begin to bite faster in the rain. Those meters "gained" before the bike starts to slow down are quite nice. In city traffic, you don't need to go for KOMs to end up close to other riders, doing stuff rather unexpectedly.
I don't think I'll ever build up another rim brake bike for my own use. Not even an "optional ride" road bike.
I'm too fond of the early onset braking in rain, and the lighter lever force required.

Disc brake advocates fail to note one key detail.

Braking power is limited by the brakes. It's limited by the maximum g-force that can be tolerated before causing an endo. The fact that rim brake users have been doing endos in panic stops for decades proves the point.

This isn't to say that disc brakes don't have better initial response in wet conditions, but ALL arguments about braking power are moot.

BTW- expect makers to very carefully engineer the maximum braking power for disc brakes, because too much brake can be as or even more dangerous than not enough brake. Trying to find ways to ensure adequate braking power yet, preventing endos from too much braking has long been a challenge, and historically makers have faced more suits over brake induced endos than over inadequate braking power.

man this is a bunch of crap.

The facts are there. Some people just refuse to see them

The INTERPRETATION of those facts as it affects each rider varies with each rider and each ride.

This means .... wait for it ...

NEITHER ARE BETTER and ...... BOTH ARE BETTER.

This logic is flawless!:thumb:

Mechanical disc brakes imho are overrated.

Negative acceleration is overrated.

In the case of a really long hill with a stop sign at the bottom.

Disc brakes are absolutely the WRONG choice. Disc brakes overheat and lose braking power over long steep descents where as rim brakes do not. Given ample braking time, rim brakes always come out on top. The only "advantage" discs have is the "modulation" provided by them (and proven wrong by Simon in the video). Modulation only comes into play when you're panic stopping or running at the edge of the grip of the tires.