For once I agree with Lenard Zinn - Road disk shortcomings

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Guerdi
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by Guerdi

What about the disk rubbing against the pads ? I have had that issue with an older generation mtb (xtr 960), and it was very annoying. Eveything was faced on the bike but the noise was still there.

Is that problem fixed with new generations brakes ? I'd hate to hear such a noise on my road bike.

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refthimos
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by refthimos

r_mutt wrote:why doesn't the cycling industry reach out to the motorcycle industry for their expertise on this matter? motorcycles have been using discs since the late 60's. if anyone can solve these potential "problems", it would be a company like Brembo.


The expertise is already there - its in MTB disc brakes. The MTB guys have already sucked just about all the know-how you can imagine from the motorcycle guys, and have in fact pretty much dialed-in disc brakes for bicycle use.

The middle (and eventually, low end of the market when the tech trickles down) will eagerly adopt disc brakes for road use. The high end will resist, not so much for the weight penalty (we already see even hardcore racers willing to take a weight penalty for a powermeter, a comfy saddle, aero wheels, di2, etc) but because of the aero penalty.

Then again, if we start seeing more wind tunnel tests like the SD test that found that once you actually put a pedaling rider on a super aero bike, there is no drag difference between that and the same rider on a "barely aero" bike (the theory being that the legs spinning churn up so much air around the frame that aero frames don't do anything/do very little in real life use), then maybe people racers will decide that the aero penalty isn't real - and road discs will offer advantages in braking, lighter carbon rims, carbon clinchers that won't melt under hard braking, etc).

Then again, if that is the case, I will need to sell my S5 and manufacturers will have to tell us that we have been wasting our time and money on these new "aero" frames.

I think in the end though, adoption at the high end will be difficult due to the aero concerns.
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Epic-o
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by Epic-o

eric wrote:Zinn wrote "I believe you can find brake-cable housing that combines coaxial strands to prevent compression of its length with spiral winding to prevent bursting."

Who makes that?


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Epic-o
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by Epic-o

r_mutt wrote:why doesn't the cycling industry reach out to the motorcycle industry for their expertise on this matter? motorcycles have been using discs since the late 60's. if anyone can solve these potential "problems", it would be a company like Brembo.


Brembo came to the bicycle industry and their bicycle brakes weren't better than the rest despite being way more expensive

blantonator
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by blantonator

Guerdi wrote:What about the disk rubbing against the pads ? I have had that issue with an older generation mtb (xtr 960), and it was very annoying. Eveything was faced on the bike but the noise was still there.

Is that problem fixed with new generations brakes ? I'd hate to hear such a noise on my road bike.


this hasn't been a problem for a long time. My M980 brakes are unbelievable. Amazing power and modulation.

bm0p700f
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by bm0p700f

Well as user of MTB discs I do wonder what has taken so long for road bikes to have mounts for these.

I find nothing wrong with good rim brakes but discs on a road bike are something that excites me a little even though I really don't need them in sunny (currently) suffolk.

1. rims that do not wear out.
2. no machined sidewalls means cheaper rims
3. rim profile can be changed providing some (hopefully) aero advantage.
4. carbon rims will become much more propular.
5. rim will surely become lighter in disc only versions.
6. Hopefully 135mm rear hub O.L.D will catch on reducing poor dish and allowing more durable wheels. It is only going to get worse with shimano 11 speed.

Shame it going to be a custom frame to get them now.

roca rule
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by roca rule

bm0p700f wrote:Well as user of MTB discs I do wonder what has taken so long for road bikes to have mounts for these.

I find nothing wrong with good rim brakes but discs on a road bike are something that excites me a little even though I really don't need them in sunny (currently) suffolk.

1. rims that do not wear out.
2. no machined sidewalls means cheaper rims
3. rim profile can be changed providing some (hopefully) aero advantage.
4. carbon rims will become much more propular.
5. rim will surely become lighter in disc only versions.
6. Hopefully 135mm rear hub O.L.D will catch on reducing poor dish and allowing more durable wheels. It is only going to get worse with shimano 11 speed.

Shame it going to be a custom frame to get them now.

1 honestly how long does it take for a rim surface to wear out. (you will need to change pads that might be more expensive and the rotor)
2 just because it is cheaper to manufacture does not mean that manufacturers will pass on the savings to me or to you
3 if it is a clincher you still need to have structura integrity on walls and you limitation is that not the braking surface.
4 carbon rims will be more popular if they were cheaper ( they are pretty popular for what they cost)
5 or it might become heavier ( more spoke; longer spokes; and beefed up eyelets to resist the pulling force of spokes.
6 as it is a lot of fellow weenies complain that some crancksets have wide q factors.
let's face it riders like myself and the schlecks will still ride the brakes for too long and overcook the turns. disc brakes are not going to dramatically increase ones ability on the bike, just like di2 did not stop andy from dropping his chain.

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kbbpll
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by kbbpll

I'm not sure why I even need brakes (and I regularly descend 3000' in 11 miles), but I guess in a few years I'll have to search high and low for a frame/fork that's not designed for disc.
Last edited by kbbpll on Thu Aug 23, 2012 7:51 am, edited 1 time in total.

MichaelB
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by MichaelB

roca rule wrote: ....6 as it is a lot of fellow weenies complain that some crancksets have wide q factors.
let's face it riders like myself and the schlecks will still ride the brakes for too long and overcook the turns. disc brakes are not going to dramatically increase ones ability on the bike, just like di2 did not stop andy from dropping his chain.


He was on SRAM then ....

many of the issues that people raise, are, for the majority, minor.

Many of the peiople that raise those objections, also have very little proof (engineering wise) of their suppositions, let alone actual experience of riding a drop bar road bike with discs.

Those that have done it (ridden a road bike with discs) know the benefits, and these far outweigh the negatives.

njleach
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by njleach

Are discs on a road bike really solving a problem?

It's only in super wet conditions that I find braking an issue on standard brakes. The pro's don't seem to have a problem braking down alpe d'huez, tourmalet etc... - and isn't the idea they brake as little as possible for the fastest descent? Or are we saying that disc brakes will allow them to go even faster and brake later?

Really wet conditions fair enough, standard brakes are sh!t

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by Butcher

MichaelB wrote:
roca rule wrote: ....6 as it is a lot of fellow weenies complain that some crancksets have wide q factors.
let's face it riders like myself and the schlecks will still ride the brakes for too long and overcook the turns. disc brakes are not going to dramatically increase ones ability on the bike, just like di2 did not stop andy from dropping his chain.


He was on SRAM then ....



But Andy has also dropped chains on the Di2. Once coming out of the starting gate of a TT if I recall.

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prendrefeu
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by prendrefeu

njleach wrote:Are discs on a road bike really solving a problem?


Yes, the Bicycle Industry needs to increase sales. That's the problem that needs to be solved.
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maddog 2
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by maddog 2

The pro's don't seem to have a problem braking down alpe d'huez, tourmalet etc


but they all have the same brakes... If half of them had discs then the other half would have a problem (keeping up).

Obviously the rider makes the biggest difference but descents with lots of hairpins, and technical descents with difficult bends and surfaces, would see the biggest effect of discs.

I'll say it again, it's not even close. Okay some riders are slow now and will always be slow. Discs won't solve that. But good riders will be noticeably faster. You can brake later, you have better modulation, better control, more consistency , better feel for grip....

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sugarkane
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by sugarkane

Disks brakes don't solve the problem of low skill sets..

Just what the world needs a bunch of guys with no idea about grip management, tire selection and pressure pushing downs hills at 20kph more than they used to.. :unbelievable:

I'd still ride around the out side of any one who thinks they are nessary in the wet with carbon rims brakes.

In the wet carbon rims delevelop more modulation and less power. Not a bad thing as your level of grip decreases massively. You have to keep the bike more upright, brake more upright and use both brakes more to keep the bike balanced, less tire pressure is a good idea too and take the gentlest line through the corner.. None of these things are suddenly gona magically start happening cause you get some disk brakes


In the dry you could use the increase in power to totally out brake people in really tight corners up the inside but we are not racing motor bikes here, and even most crit racing isn't that cut throat


Brakes don't make you fast around corners.. Not using them does... :roll:

I totally agree with prendrefeu :thumbup:

VNTech
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by VNTech

sugarkane wrote:Brakes don't make you fast around corners.. Not using them does... :roll:


That's a truly silly statement.

I'm with Lennard on the technical problems, we've discussed it numerous times. I'm not yet sold on them, at least in anything like their current form, for road racing. But anyone who says that discs won't provide a substantial improvement to actual brake performance (not talking aerodynamics, or weight, etc etc) is just offering up proof that they haven't been on a good mountain bike in about four years.

I got caught in the rain coming out of the mountains today. Carbon clinchers, Swissstop pads. It's actually a pretty good combo, as carbon in the rain goes, but I still had very little actual brake power. The assertion that brake power falls in line with tire traction in the rain is false. Tire traction decreases only slightly in the rain (except for on paint and such), while brake power, particularly on carbon, all but disappears. Plus I have no brake pads left now.

In other words: I'd absolutely love to have a set of discs on my training bike... and probably my race bike within a few years.
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