Why is no one using disc brakes in the tour?

[DOUG]

:lol: I'll make sure to run my purchasing decisions past "the Europeans" before buying anything then. Oh wait I already ride a road bike with discs! Hopefully the superior braking in the dry and much better performance in the wet will make up for my lack of experience

You guys crack me up.

Just curious how you define superior. I've raced bicycles, motorcycles, and cars. Superior means many different things in each of these formats. I'm wondering what you mean by "superior" braking.

Before you say something foolish, you might want to read something by a brake engineer http://www.scirocco.org/faq/brakes/pulpfriction/pfpage1.htmlwhose credentials include http://www.teamscr.com/about-james-walk ... r-jr~.html vehicle stability systems for OEMs.

Suffice it to say, regardless of your religion, the tire determines your braking performance regardless of how you choose to extract heat from forward motion.

Thanks but I understand how braking works, maybe you don't? I'm not going to bother going through all the advantages vs disadvantages as thats been done ad nauseum on here and on every cycling forum in existence but i will say that disc brakes are far more efficient at converting kinetic energy into heat so I guess you're proving my point for me. As a Mechanical Engineer, motorcycle, car, MTB and road racer I'm in a good position to assess the benefits of disc brakes. I've thought about it carefully and have a lot of experience riding both systems in a range of conditions over many years.

I hope I'm not considered "foolish" but thanks for your concern Have you ridden a disc brake bike for more than 5 minutes? If so what is your perspective on disc vs. rim?

[Marin]

Coming from MTB, I have ridden more disc brakes than rim brakes in the past 10 years, and I still prefer rim brakes for road bikes by far.

[kgt]

As Marin says it is more a matter of preference.
Performance is not something ideal but is always connected to the intended use. So the right question is not which brakes are more powerful but how a rider wants his brakes to perform. Of course, a set of 4 piston Brembo discs would stop any wheel at any speed. But are these suitable for a road bike? No. For the 99% of cases a good set of rim brakes (not all rim brakes are good) is more than enough for a road bike even in pro racing conditions. As for the less experienced amateur a set of alu rims is just fine.

[Ticlimax]

Funny enough it always seems weird to me that the discussion of which brakes is about the actual braking . No rim wear is the most important reason why I'm going disc. Then again, at 58kg and living in a flat area, braking has never been an issue.

[snowdevlin]

Funny enough it always seems weird to me that the discussion of which brakes is about the actual braking . No rim wear is the most important reason why I'm going disc. Then again, at 58kg and living in a flat area, braking has never been an issue.

You live in a flat area, weight 58kg... and your concern is rim wear?

hummm....

you ride chinese carbon clinchers?

[Ticlimax]

Funny enough it always seems weird to me that the discussion of which brakes is about the actual braking . No rim wear is the most important reason why I'm going disc. Then again, at 58kg and living in a flat area, braking has never been an issue.

You live in a flat area, weight 58kg... and your concern is rim wear?

hummm....

you ride chinese carbon clinchers?

Yes indeed .

[Marin]

Funny enough it always seems weird to me that the discussion of which brakes is about the actual braking . No rim wear is the most important reason why I'm going disc. Then again, at 58kg and living in a flat area, braking has never been an issue.

Umm, I've been riding a 50x23 set of Chinese carbon clinchers since 2014. There's no discernible wear on the braking surface. 77kg, and I ride in the Alps.

[Ticlimax]

Funny enough it always seems weird to me that the discussion of which brakes is about the actual braking . No rim wear is the most important reason why I'm going disc. Then again, at 58kg and living in a flat area, braking has never been an issue.

Umm, I've been riding a 50x23 set of Chinese carbon clinchers since 2014. There's no discernible wear on the braking surface. 77kg, and I ride in the Alps.

With Chinese carbon, you either get lucky or you don't. With discs, I feel safe enough to take to take the gamble. Wear on the brake surface also depends on the kind of conditions you ride in. I want to feel comfortable taking on gravel/rain/easy singletrack as well as summer rides in the tarmac. In the end for me, if it only gives me peace of mind, it is still worth it.

[Marin]

With Chinese carbon, you either get lucky or you don't

I'm not talking about sudden defects but about brake track wear?

[Ticlimax]

Defects and brake track wear are related though. If carbon rims fail, isn't it usually near the brake track from being weakened through wear?
Anyhow I've yet to see a failure of a Chinese disc wheel that wasn't crashed, whereas there are plenty of horrorstories to be found on their rim-brake counterparts, even from fellow flatlanders. I do believe you've made a good purchase, without doubt, I just won't take the chance.

[AJS914]

If carbon rims fail, isn't it usually near the brake track from being weakened through wear?

Probably not from mechanical wear. The likely culprit is over heating the resin beyond it's temperature range. I've heard about enough people over heating a Chinese carbon clincher so I'm not willing to take the risk. Combined with the high shipping cost to take advantage of warranty, I'll just stick with aluminum for now.

[themidge]

Has anybody else noticed that in every disk vs rim brake test, (at least all the ones that I've seen) they are always testing metal disks (steel, alloy?) against carbon rims. It seems to me that this isn't a fair comparison and instead it should be metal disks against metal rims (alloy)

[Franklin]

First of, the big advantage is the usage of carbon rims, so it's a very valid use-case. Secondly, if you think an alloy rim will magically improve braking up to disc standard? No. Not even a Magura rim brake is able to stop as fast as a disc. And in the wet the difference is a few meters. Add in handling and dosing and it's functionally one of the biggest jumps in technology.

That's not opinion, but cold hard facts borne out by physics and tests. That people are denying it is similar to the friction/index discussion, which was just as hilarious. In a few years we will look back while shaking our heads. Discs will take over and especially for the consumer, this will be a big step up.

[Marin]

cold hard facts borne out by physics and tests

Braking distance is limited by tire traction, not brake type, and I can brake hard enough to lift my rear wheel on almost all of my bikes, rim or disc.

The one bike where I can't is my BMX. It doesn't have a front brake.

[maddog 2]

Braking distance is limited by tire traction, not brake type, ..

The nugget that keeps on giving Braking distance is down to the rider's ability to modulate braking power. For front end braking (in the dry) this isn't anything to do with tyre traction, as you'll go over the bars before you lock up the tyre. So it comes down to how close you can get to lifting the rear wheel, and discs modulate much better than rim brakes in doing this. Rim brakes are harder to hold on this balance point, and the blocks get hot and so their consistency suffers.

and I can brake hard enough to lift my rear wheel on almost all of my bikes, rim or disc.

I wouldn't dispute this. But you can hold it at this point with more control on discs.