Disc Road bikes in 2013-14, will it happen in mass?

Back by popular demand, the general all-things Road forum!

Moderator: robbosmans

mentok
Posts: 577
Joined: Sun Jan 01, 2012 9:58 am

by mentok

eric wrote:More braking power isn't useful as tire traction limits braking.


It's not about the power, it's about the control that a hydraulic set-up allows. wrt rim brakes, lack of control limits braking. lack of control is what causes you to lock up before the limits of controlled traction are properly reached. the fine control to maximise braking force just isn't possible when your hand is directly applying the clamping force to the rim.

whether the degree of control offered by a hydraulic disc set-up is actually needed or warranted on a road bike is the point for debate, but to say that a rim brake is able to effectively utilize all available braking traction of a road tyre is false.

eric
Posts: 2196
Joined: Tue Nov 11, 2003 9:47 pm
Location: Santa Cruz, California, USA
Contact:

by eric

mentok wrote:It's not about the power, it's about the control that a hydraulic set-up allows. wrt rim brakes, lack of control limits braking. lack of control is what causes you to lock up before the limits of controlled traction are properly reached. the fine control to maximise braking force just isn't possible when your hand is directly applying the clamping force to the rim.


VERY few people have the skills to brake right at threshold. I have seen motorcycle road racers who could brake so hard that their rear tire was a few inches to a foot in the air, but even among that crowd that is a very rare talent. Maybe you have that, but it's unlikely.

For normally talented people, the difference in actual braking force due to better modulation between good mechanical rim brakes and hydraulic discs is going to be very small.

But it's one of those things that disc proponents will argue, because it can't be dis proved.

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

www.starbike.com



airwise
Posts: 1018
Joined: Tue Jul 27, 2010 8:31 pm

by airwise

I'd be interested in knowing how many of the naysayers on this thread have ridden discuss on long mountain roads and are therefore qualified to offer an opinion on the relative merits of the two setups?

It seems those that have are aware of the benefits and those that haven't insist there aren't any.

With regards to aerodynamics, I'm not sure why a disc would be of benefit on a flat tt or in a triathlon. But some on here are suggesting wheels are already as aero as they can be? Really? Would be good to get some real aerodynamicists on here that work at the cutting edge.

MichaelB
Posts: 995
Joined: Tue Apr 22, 2008 4:31 am

by MichaelB

prendrefeu wrote:
MichaelB wrote:If you haven't yet done it, grab an opportunity to ride a ROAD disc bike, esp in the rain, and see the reality.


Paradoxical statement. Grab an opportunity to ride especially in the rain?

I can see road discs being great for those of you who live in areas with, frankly, shit weather. That's great. For you.

....


Living in Adelaide (South Australia), there are niether alpine passes nor $hit weather. There are timess when it rains during a ride (if it raining at the start of a ride, I tend not to go out, yes, I'm a wuss), I am grateful that I have brakes that work in the wet.

It's great that many people are very happy with their rim brakes. Great.

As there are many people who also fall victim to marketing hype (disc and non-disc), well all have different opinions on what REALLY makes a difference.

My point that was quoted by prendrefeu, was more aimed to get people to give their opinions AFTER they have ridden a disc equipped road bike, rather than hypothesise based on no knowledge or experiences om MTB's or CX bikes (better than nothing, but still different).

Meh, I like them, they suit my riding and I'll keep on them.

YMYV.

Svend p
Posts: 4
Joined: Wed Jun 06, 2007 8:54 pm
Location: Aarhus, Denmark

by Svend p

I for one can't wait for road disc brakes.

I have worn through rims on my mountain-bike and commuter-bike due to wear from rim brakes, resulting in blown tires and I was once close to having my leg pierced by the sharp edge of the rim pointing out when that happened. Now both of them are disc brake equipped. :-)

As for stopping power, I have not tried disc brakes that were as powerful as rim brakes - at least not in the dry. Possibly this could be because of lack of experience, since I haven't tried a proper lightweight road bike with high end disc brakes. But the best brakes I have experienced, was on my Cervelo Soloist Carbon with Dura Ace 7800 on Fulcrum 1 wheels. I was able to break in the manner eric described, where the rear wheel lifted just a little bit. Because of the sheer thrill of the G-forces, I would actually do this as often as possible. ;-)

I also suffer from squeaking from the disc brakes. Whether in the city or the forest, people look very annoyed at you when your brakes squeal. For this alone, it would be worth the premium for the Kettle carbon rotors if the were virtually quiet during breaking, which I would expect them to be?!

Despite these complaints, I STILL want disc brakes for my road bike. I just like the idea that I'm not grinding away on my rims every time I break. I like that they work in the wet. I like that my wheels will not get dirty from break pad residuals. And I love that they are always perfectly adjusted.

I'm contemplating on getting a Specialized Crux Pro Carbon Disc as my road bike, even though it is a cross frame. Since my main target is a comfortable ride, I think it will do the trick. The Cervelo beat me up, so I got a little weary of it, but that might partly have been because the frame was too small for me (56 cm frame, I'm 184 cm). With the red Kettle rotors, I think it would look like a proper racing bike, and not like a commuter bike.

I'm just waiting for Shimano to bring out Dura Ace hydraulic brakes and a proper 1x11 road gearing setup like the SRAM XX1 - another thing that came from mountain biking which I think is brilliant. Hopefully summer is not over when this happens - we still have a little bit of snow here in Denmark so for now I can wait.

sawyer
Posts: 4485
Joined: Fri Dec 15, 2006 7:45 pm
Location: Natovi Landing

by sawyer

airwise wrote:I'd be interested in knowing how many of the naysayers on this thread have ridden discuss on long mountain roads and are therefore qualified to offer an opinion on the relative merits of the two setups?
.


I think quite a few of the naysayers, myself included, would agree there are benefits for those who ride in wet mountains.

But I rarely do ... so I'll take rim brakes and live with the sub-optimal braking when I am in the wet mountains.
----------------------------------------
Stiff, Light, Aero - Pick Three!! :thumbup:

airwise
Posts: 1018
Joined: Tue Jul 27, 2010 8:31 pm

by airwise

Sawyer, I'd say the benefits are as apparent In the dry to be honest but then maybe this conversation would be best served by being put on hold pending people actually trying the things.

KLabs
Posts: 380
Joined: Wed Dec 01, 2010 4:29 am

by KLabs

Svend p wrote:I for one can't wait for road disc brakes.
... I'm just waiting for Shimano to bring out Dura Ace hydraulic brakes and a proper 1x11 road gearing setup like the SRAM XX1 - another thing that came from mountain biking which I think is brilliant. Hopefully summer is not over when this happens - we still have a little bit of snow here in Denmark so for now I can wait.

Hi Svend p, 10-42T cassette and single 46T up front (no good for sprinting though) ... awesome :)
Hydraulic disc brakes with a light aero cowling ... awesome :)
Riding in the hills (wet or dry) ... awesome :)

thanks KL :)

User avatar
maddog 2
Posts: 366
Joined: Wed Feb 25, 2009 7:58 pm
Location: Lancaster, UK

by maddog 2

It's really quite simple... discs provide much better braking than rim brakes*, but they are a bit heavier (and maybe less aero but I'm still not sold on this personally).

so...

If you ride in smooth, flat, sunny places then a) I hate you (the smooth, sunny bit) and b) you probably don't need the extra braking performance

If you are steady away down the hills then you probably don't need the extra braking performance

If you are obsessed with aero and weight (god forbid) then you probably don't want to put braking effectiveness over weight

But if you ride in steep, rough, wet places, such as the UK then you will love the extra consistency, power, control and the fact that your expensive rims don't fall apart in 12 months.

* I have two road bikes, one with DA rim brakes, and one with discs, so I can actually comment on this with actual data. You don't need long Alpine descents for this to be apparent - even short, steep stuff is much quicker and safer with discs.

sawyer
Posts: 4485
Joined: Fri Dec 15, 2006 7:45 pm
Location: Natovi Landing

by sawyer

maddog 2 wrote:It's really quite simple... discs provide much better braking than rim brakes*, but they are a bit heavier (and maybe less aero but I'm still not sold on this personally).

so...

If you ride in smooth, flat, sunny places then a) I hate you (the smooth, sunny bit) and b) you probably don't need the extra braking performance

If you are steady away down the hills then you probably don't need the extra braking performance

If you are obsessed with aero and weight (god forbid) then you probably don't want to put braking effectiveness over weight

But if you ride in steep, rough, wet places, such as the UK then you will love the extra consistency, power, control and the fact that your expensive rims don't fall apart in 12 months.

* I have two road bikes, one with DA rim brakes, and one with discs, so I can actually comment on this with actual data. You don't need long Alpine descents for this to be apparent - even short, steep stuff is much quicker and safer with discs.



Never had an expensive rim fall apart in 12 months! Or fall apart ever for that matter.

Perhaps I brake less than you? Where do you do most of your riding?

I'd also include the travel risk ... damage a disc set-up in transit and it will be hard to fix. And I'd suggest they are more vulnerable to damage given their design, where they are positioned on bike and so on.
----------------------------------------
Stiff, Light, Aero - Pick Three!! :thumbup:

JMT
Posts: 36
Joined: Wed Feb 22, 2012 3:16 pm

by JMT

I think main group that would benefit from hydraulic brakes are people who tend to commute on racing bikes (typically to be able to train before or after work) in high traffic environments or train in bad weather, as prendrefu pointed out.
A lot of people do fit into this category so if they'd start selling road hydraulic brakes I'd consider a fork and front brake at least, I don't really see a need for it in the back.
The main deficiency of rim brakes for me is that to get maximum braking power, my hands need to be in the drops, from there I can go up on my front wheel if traction is good and I brake hard. When commuting however I much prefer the hoods as I get a better view of my surroundings, and from there I don't get the same leverage.
For training and commuting I don't care about aero

xnavalav8r
Posts: 2594
Joined: Mon Jan 21, 2008 12:09 pm

by xnavalav8r

I had a disc-brake equipped road bike in 2006. I regret getting rid of it. It wasn't very light, but it could have been with today's developments. Discs are the future.

viewtopic.php?f=3&t=40430&hilit=morati

winky
Posts: 84
Joined: Sun Feb 10, 2013 5:11 pm

by winky

I can't believe I'm saying this, but I was once a pure traditionalist who used to say that road discs are a solution to a problem that doesn't exist. However the unthinkable happened in the last year...

I tried road discs. Yep. A friend bought a custom bike fitted with Avid road discs. You know what? The power and modulation was there! And this is Avid's cable-actuated BB7 brakes and I must admit, those are quit good for a disc brake that isn't hydraulic. I am a total believer now. I can't wait until hydraulic road discs come out! Anyone who says that mechanical disc brakes are no good is sooooooo full of sh:t it ain't even funny.

Road discs are here to stay. You just have to try it. I did. It works. And it works well.

KLabs
Posts: 380
Joined: Wed Dec 01, 2010 4:29 am

by KLabs

Hi winky, yep, yes, absolutely ... thanks KL :)

MichaelB
Posts: 995
Joined: Tue Apr 22, 2008 4:31 am

by MichaelB

winky wrote: ...... You just have to try it. I did. It works. And it works well.


What I have been saying all along

:welcome: to the club

:mrgreen:

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

www.starbike.com



Post Reply