Disc brakes on road bikes...

[Benotti69]

I think if you read Bustedknuckles posts he has a lot of experience in the bike industry. He also calls a spade a spade.

His experience of sram products are first hand. He posts a lot of sense, something most manufacturers lack in their search for bigger profit margins.

Just so we're clear I'm 21 years in the industry. Cut my teeth at several shops in the beginning, 2 distributors, owned a sales rep company, and my current company for the last 8 years. I do contract R&D for a few part manufactures, all of which I have active running NDA's. Brands that are talked about here and on other forums regularly.

Now that my credentials are out of the way, do you finally have anything to add to the conversation about disc brakes on road bikes?

Personally I think it's amazing you have 21 years in the industry when my impression based on this thread is that you maybe aren't that old.

They're brakes. Who cares? Ride 'em or don't.

The question to be answered is whether we'll be offered the choice if we want to buy a new bike a few years from now.

I guess stock piles will allow a choice. It may be different for the latest racing bike set ups, in the future, if the whole peloton goes disc, but i really can not see that happening. Some pros still have not gone electronic shifting.

 

[carton]

The thing I feel often gets left out of the issue is trickle down potential. Ultegra brakes on a $2,000 alloy-rimmed road bike are pretty good. So the XT brakes on your average $2,000 MTB. Comparable? I'd say no, but plenty differ. But the cheap Tetkro brakes on a $500 road bike are absolute crap next to the cheap Tetkro hydro brakes on $500 MTB. I think your average beginner would be so much better served when the tech trickles down. YMMV, as always.

 

[dsut4392]

Re:

The thing I feel often gets left out of the issue is trickle down potential. Ultegra brakes on a $2,000 alloy-rimmed road bike are pretty good. So the XT brakes on your average $2,000 MTB. Comparable? I'd say no, but plenty differ. But the cheap Tetkro brakes on a $500 road bike are absolute crap next to the cheap Tetkro hydro brakes on $500 MTB. I think your average beginner would be so much better served when the tech trickles down. YMMV, as always.

Not really sure what you're trying to say about trickle-down potential. Tektro branded brakes are built to a pricepoint, whereas the Shimano Ultegra/XT brakes are positioned as 'top performance at a reasonable price'. Having ridden multiple brands of MTB disc brakes since 2003, I have to say that (reliability aside), it's seems to be hard to build a hydro disc brake that doesn't work pretty well. And on the reliability stakes, some of the more 'agricultural' low cost brakes seem just fine. Perhaps it's just not possible to skimp on costs on a hydraulic brake in a way that you end up with a 'functional' but poorly performing product? Road brakes not so much - stick some horrible rock hard pads on some flexy calipers, and activate them via some poorly routed budget cable & housing and you get truly awful performance.

 

[Stingray34]

Good question. I really dislike sram after being treated so poorly over the phone by one of their 'big boys(as a bike shop owner)..But disc brakes on enthusiast's ROAD bikes is really dumb, shoved into the market place by mostly spam. 2015/6 SR/Record/Chorus is really brilliant..with more functionality(multi up shifts to higher gear)..scam is junque.

I realise it's off-topic for this thread, but since you mentioned Campy, have you seen the new Potenza group? If so, what do you think?

I'm actually thinking about a 'one bike to rule them all.' I'm think Santa Cruz, Surly Steel etc., with drop bars compact crank, long-cage derailleur, MTB cassette, 35-40mm Conti Cross tires and - wait for it - Cantilevers. I love them! They are sweet.

Thinking of Potenza for it, with some handbuilt wheels.

BTW, love your steel Merckx with Deltas and ETS - best mash-up ever!!

 

[Bustedknuckle]

Good question. I really dislike sram after being treated so poorly over the phone by one of their 'big boys(as a bike shop owner)..But disc brakes on enthusiast's ROAD bikes is really dumb, shoved into the market place by mostly spam. 2015/6 SR/Record/Chorus is really brilliant..with more functionality(multi up shifts to higher gear)..scam is junque.

I realise it's off-topic for this thread, but since you mentioned Campy, have you seen the new Potenza group? If so, what do you think?

I'm actually thinking about a 'one bike to rule them all.' I'm think Santa Cruz, Surly Steel etc., with drop bars compact crank, long-cage derailleur, MTB cassette, 35-40mm Conti Cross tires and - wait for it - Cantilevers. I love them! They are sweet.

Thinking of Potenza for it, with some handbuilt wheels.

BTW, love your steel Merckx with Deltas and ETS - best mash-up ever!!

The idea that Potenza is ultegra-esque and Athena the triple/11s offering is a good move. Potenza sports a lot of the 'features' of the Chorus/Record/SR groups above(front der arm, rear der design, any CR crank) plus mid cage and big cogset. Pricing ala the deep discount UK MO places will place it around ultegra, I like it. Wish Campag made more hubs tho.

 

[veganrob]

I wish Campy made more hubs also.

 

[King Boonen]

Potenza is £100 more than Ultegra at online prices, probably close enough for some people to try it. I'll stick with 105 for the time being but when I do look for a new group for my road bike this will certainly be on my radar.

 

[Stingray34]

[quote="

Good question. I really dislike sram after being treated so poorly over the phone by one of their 'big boys(as a bike shop owner)..But disc brakes on enthusiast's ROAD bikes is really dumb, shoved into the market place by mostly spam. 2015/6 SR/Record/Chorus is really brilliant..with more functionality(multi up shifts to higher gear)..scam is junque.

[/quote][/quote]

I realise it's off-topic for this thread, but since you mentioned Campy, have you seen the new Potenza group? If so, what do you think?

I'm actually thinking about a 'one bike to rule them all.' I'm think Santa Cruz, Surly Steel etc., with drop bars compact crank, long-cage derailleur, MTB cassette, 35-40mm Conti Cross tires and - wait for it - Cantilevers. I love them! They are sweet.

Thinking of Potenza for it, with some handbuilt wheels.

BTW, love your steel Merckx with Deltas and ETS - best mash-up ever!![/quote]

The idea that Potenza is ultegra-esque and Athena the triple/11s offering is a good move. Potenza sports a lot of the 'features' of the Chorus/Record/SR groups above(front der arm, rear der design, any CR crank) plus mid cage and big cogset. Pricing ala the deep discount UK MO places will place it around ultegra, I like it. Wish Campag made more hubs tho.[/quote]

Thanks BK; I thought as much - Campy just make good stuff. Do you have any Cantilever/rim/hub recommendations? If I go Potenza it will be 11 speed. I would go triple, but the MTB stuff gives too-low top gears, and I like the compact/double Q-factor - feels road-bike sleek.

I think I speak for many when I say I really value your input - like RDV4Roubaix/GuisseppeMagneto! I have Hydro discs on my Bianchi MTB, and even though they stop brilliantly, the mineral oil thing is a worry when I stack mine and my wife's bike in the car - I quickly stick those little red caliper savers in. I don't live in an alpine area and don't need that kind of braking performance. I've ridden bikes with cable-discs - set up right they are quite good and easy to maintain.

But I'm kinda old-skool - Surly Crossmax/Cantis/drop-bars/handbuilt wheels and I can ride anywhere happy for not too much money.

 

[Stingray34]

For what it's worth, SRAM should go back to Gripshift and concentrate on the tourer market. I had Gripshift on an early MTB and it was great. Force, Rival & Red....light but not so good, but that experience was a while ago now.

 

[carton]

Re: Re:

Not really sure what you're trying to say about trickle-down potential. Tektro branded brakes are built to a pricepoint, whereas the Shimano Ultegra/XT brakes are positioned as 'top performance at a reasonable price'. Having ridden multiple brands of MTB disc brakes since 2003, I have to say that (reliability aside), it's seems to be hard to build a hydro disc brake that doesn't work pretty well. And on the reliability stakes, some of the more 'agricultural' low cost brakes seem just fine. Perhaps it's just not possible to skimp on costs on a hydraulic brake in a way that you end up with a 'functional' but poorly performing product? Road brakes not so much - stick some horrible rock hard pads on some flexy calipers, and activate them via some poorly routed budget cable & housing and you get truly awful performance.

I think you said it better than I did. This NHTSA study on disc brakes vs drum brakes in cars showed that most of the 64 lives saved a year due to the introduction of discs are due to the lower risk of failure, I wonder if the something similar applies to calipers vs. discs in bikes. Besides performance in the wet, the cheap stuff seems to me to be where the real difference lies.

 

[kwikki]

Well I absolutely love the Shimano hydro discs on one of my road bikes. It's not the total stopping power (which you can't use anyway) it's the pure progressive control and the lack of force needed to apply. Plus they work in the wet. Plus they don't trash your rims.

 

[winkybiker]

For what it's worth, SRAM should go back to Gripshift and concentrate on the tourer market. I had Gripshift on an early MTB and it was great. Force, Rival & Red....light but not so good, but that experience was a while ago now.

SRAM, typically, missed a key opportunity with Grip-shift. Way back when, we had thumbshifters. One big advantage was that you could use your thumb to feel what sprocket and chainring you were in by the position of the lever without taking your eyes from the trail. You know the idea - "Do I have a couple more sprockets at the back for this upcoming ramp, or do I have to shift the front?". We lost this ability with Shimano's Rapidfire lever-trigger-type shifters (and with road STI - but I'm talking about MTB here). They added little windows with orange pointers to some models (my old XT has them) but you still had to look down. The disadvantage of having to take your eyes off the trail to plan a critical shift is obvious. SRAM, with Gripshift could have made the rotating bit egg-shaped or with a prominent protrusion so that the position was obvious just by feel, just like in the days of thumb-shifters. But they didn't. They kept them round. So we still had to look down (or guess). A lost opportunity that left me wondering if the so-called engineers behind this system even rode bikes.

Of course, all this is now in the past. But their unspeakably ugly hydro road levers alone mean I'll never consider the brand again. For anything. They cannot be forgiven for those monstrosities. Ever.

 

[kuoirad]

For what it's worth, SRAM should go back to Gripshift and concentrate on the tourer market. I had Gripshift on an early MTB and it was great. Force, Rival & Red....light but not so good, but that experience was a while ago now.

Ugh, no thank you. *Hated* Gripshift back in the day. Hated it.

 

[Bustedknuckle]

[quote="

The idea that Potenza is ultegra-esque and Athena the triple/11s offering is a good move. Potenza sports a lot of the 'features' of the Chorus/Record/SR groups above(front der arm, rear der design, any CR crank) plus mid cage and big cogset. Pricing ala the deep discount UK MO places will place it around ultegra, I like it. Wish Campag made more hubs tho.[/quote]

Thanks BK; I thought as much - Campy just make good stuff. Do you have any Cantilever/rim/hub recommendations? If I go Potenza it will be 11 speed. I would go triple, but the MTB stuff gives too-low top gears, and I like the compact/double Q-factor - feels road-bike sleek.

I think I speak for many when I say I really value your input - like RDV4Roubaix/GuisseppeMagneto! I have Hydro discs on my Bianchi MTB, and even though they stop brilliantly, the mineral oil thing is a worry when I stack mine and my wife's bike in the car - I quickly stick those little red caliper savers in. I don't live in an alpine area and don't need that kind of braking performance. I've ridden bikes with cable-discs - set up right they are quite good and easy to maintain.

But I'm kinda old-skool - Surly Crossmax/Cantis/drop-bars/handbuilt wheels and I can ride anywhere happy for not too much money.[/quote]

Wheels-depends on you and your needs. Also hub choice. Lots of good hubs out there, some expensive(DT, WhiteIndustry, DA, Hope, Campagnolo) but shimano makes some nice, not expensive hubs too, 6800 and even 5800. Velocity also makes some nice ones..can be pricey tho.

Rims-DT(my favorite, DT440), Velocity, H+Son, Pacenti..all good. HED are nice but not sure why an asian made rim is so expensive.

Spokes-Sapim(what I use now), DT..

Find a good local wheelbuilder who can design and build a set for you and your needs.

I design and build wheels also and if you are in the US, I can build and send.

[email=pchisholm172@gmail.com]pchisholm172@gmail.com[/email]

Thanks for the compliment, BTW-yup, bikes is some fun stuff.

 

[StyrbjornSterki]

...It's not the total stopping power (which you can't use anyway) it's the pure progressive control and the lack of force needed to apply....

That is something that cannot be overemphasised. If you have enough braking power to lock a wheel, you already have all the power you could use. The rest is mostly down to lever effort and ease of modulation.

...This NHTSA study on disc brakes vs drum brakes in cars showed that most of the 64 lives saved a year due to the introduction of discs are due to the lower risk of failure, I wonder if the something similar applies to calipers vs. discs in bikes....

I think you're blowing their conclusions out of proportion. There is nothing in the linked report to indicate whether the "brake defects [which] had been a contributing factor" were there result of bad design, bad manufacturing, or bad maintenance. The distinction would be highly relevant to this argument. Further, the report stipulates,

...The specific estimate of disc brake effectiveness is made with less certainty than for dual master cylinders, but at least it can be said that disc brakes are not harmful and in all likelihood beneficial, on the one hand, and do not have very large safety benefits, on the other....

Not exactly a ringing endorsement.

And I have no idea why you would try to link drum brake failures to caliper rim brakes because the two bear only scant resemblance, while the caliper rim brakes and the hydraulic disc brake are close cousins. Hydraulic or cable actuated, the brake device itself provides its own opposing force, trapping the braking surface between its arms. Even the name of the braking device itself in both cases is the same, a "caliper." The only opposition to the outward pressure from the shoes of the drum brake is the very structural integrity of the drum. Little wonder drums are more prone to catastrophic failure.

 

[StyrbjornSterki]

Mechanical engineering is the science of compromise. While the advantages of disc brakes increase with the severity of the braking demands, they also decrease with its lack. Colin Chapman, legendary engineer and founder of Lotus Cars, won seven Formula One World Constructors Championships with cars of his own design and construction. Which I think settles the matter of his expertise on the matter of braking.

Lotus were still building (highly-touted) road-going sports cars with drum rear brakes at the time of Chapman's untimely death in 1982. The reason being, Chapman understood that when a driver was hard on the brakes, the weight shift onto the front tyres left the rears applying so little pressure to the roadway that the rear brakes' contribution to total braking force always was only going to be very slight, and well within the performance capabilities of (cheaper) drum brakes. So the additional cost of rear discs would have brought with it no appreciable performance benefit. Drums were adequate, and adequate sometimes carries the day.


I do have discs on my best MTB, but not because I find V-brake's overall stopping performance wanting. I have them because I am willing to go the disc brake upcharge to avoid the frustrations brought on by mud accumulating about rim brakes. My best road bike doesn't even have dual pivot calipers, just single-pivot Cane Creek 200SLs. Because I have realistically analysed my (admittedly modest) braking needs and the Cane Creeks -- at least with the addition of Kool-Stop's (high-friction, fast-wearing) salmon pads -- are adequate to them.

Because these brakes weigh just 207 grams for the pair (actual weight, after acid-dipping), to include pads and all attaching hardware. And the cost, including the lightening, was just 200 Euro. For the pair. That is a compromise I can live with. And do. Wake me when you've found disc brakes that can best those numbers.

 

[kwikki]

Wake me when you find rim brakes that work in the rain......immediately.

That's why they are on my winter/spring bike. But yeah...can't really see the point of them on race bikes (yet)

 

[Benotti69]

Re:

Wake me when you find rim brakes that work in the rain......immediately.

That's why they are on my winter/spring bike. But yeah...can't really see the point of them on race bikes (yet)

Touching a front disk brake in the rain on a descent is just going to throw you off the bike.

 

[kwikki]

Thats absolute rubbish

 

[Giuseppe Magnetico]

Re: Re:

Touching a front disk brake in the rain on a descent is just going to throw you off the bike.

By your account I should be hitting the deck regularly, it rains a lot here. But I digress, sounds like you're speaking from years of experience with disc brakes in the wet.

 

[Benotti69]

Re: Re:

Touching a front disk brake in the rain on a descent is just going to throw you off the bike.

By your account I should be hitting the deck regularly, it rains a lot here. But I digress, sounds like you're speaking from years of experience with disc brakes in the wet.

Disc brakes have been on 2 wheels for a long time.

 

[kwikki]

Re: Re:

Touching a front disk brake in the rain on a descent is just going to throw you off the bike.

By your account I should be hitting the deck regularly, it rains a lot here. But I digress, sounds like you're speaking from years of experience with disc brakes in the wet.

Disc brakes have been on 2 wheels for a long time.

Yes. I've been using them for 14 years on the road (Cannondale Cyclo-cross disc was my first road oriented disc bike). In that time I've never lost the front wheel in the wet or even come close. I now have even more powerful hydros on a pure road machine and actually I am far less likely to lose control than on rim brakes because hydro discs are so predictable. Rim brakes snatch in the wet because it takes a few revolutions for the pads to wipe off the water, which acts as a lubricant. You pull on them and nothing happens for a second or two, then all of a sudden the braking kicks in.

I'm sure you are a great guy, and know a lot of things about other aspects of cycling but as with all things in life it is always better to speak from an informed position.

 

[jmdirt]

For what it's worth, SRAM should go back to Gripshift and concentrate on the tourer market. I had Gripshift on an early MTB and it was great. Force, Rival & Red....light but not so good, but that experience was a while ago now.

You lost there. Great compared to what?

 

[King Boonen]

Gripshift was absolutely terrible.

 

[blutto]

Re: Re:

Touching a front disk brake in the rain on a descent is just going to throw you off the bike.

By your account I should be hitting the deck regularly, it rains a lot here. But I digress, sounds like you're speaking from years of experience with disc brakes in the wet.

Disc brakes have been on 2 wheels for a long time.

Yes. I've been using them for 14 years on the road (Cannondale Cyclo-cross disc was my first road oriented disc bike). In that time I've never lost the front wheel in the wet or even come close. I now have even more powerful hydros on a pure road machine and actually I am far less likely to lose control than on rim brakes because hydro discs are so predictable. Rim brakes snatch in the wet because it takes a few revolutions for the pads to wipe off the water, which acts as a lubricant. You pull on them and nothing happens for a second or two, then all of a sudden the braking kicks in.

I'm sure you are a great guy, and know a lot of things about other aspects of cycling but as with all things in life it is always better to speak from an informed position.

....yeah you are so absolutely right and here is a comment from my informed position....I've been driving a car with disc brakes for over 25 years and this funny thing happens when it rains, the road gets much more slippier and even small gradient changes and surface imperfections become an issue and in winter when roads are often covered in snow or ice the situation is much more most worser and frankly it doesn't matter how much more superior a brake system may be theoretically it is the operator who is the prime variable in deciding how successful a stop will be....

...bottom line, some brake systems make have certain theoretical advantages in certain advantages but as was pointed out up thread engineering is about applying a solution that balances advantages....so yeah in a mtn bike situation where tire grip is relatively huge more braking power is a good thing but on the road where your limiting factor is tire road interface , not so much if at all...

...now about the only thing that disc brakes have a marked advantage in is with poseurs who really really need bling carbon wheels but can't be bothered to learn how to properly mount tubular tires..... and oh its really good for the bike industry which , if disc brakes become ubiquitous, can sell more bling carbon wheels to said poseurs ( who after all make up the majority of the market )...

Cheers