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

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bobqzzi
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by bobqzzi

I'm sure we will see a raft of them because they are away for the bike industry to offer something new. That said, they seem pretty useless on road bikes.

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Ritterview
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by Ritterview

spytech wrote:we now have carbon ceramic rotors from kettle cycles that weigh 50 - 60g depending on size. Spyre SLC 141g w/rotor - even less with the Kettle cycles carbon ceramic rotors. we could get to sub 250g disc brakes for front and rear calipers/rotors.


Tandems have been using rotors for the road for a while. The latest developments really do seem to promise a weight reduction.

My Kettle 203 mm rotor has shipped, for use on my tandem. We'll be putting it to the heat test.

The 141 (or is it 146?) gram Spyre mechanical disc looks to be the bee's knees. The Avid BB7 has been the dominant and unchanged mechanical disc for years, and it is great to see new developments. I wonder how much of the Spyre's hardware is steel, and could be replaced with Ti for a further weight savings?

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If so, somebody please get together a Spyre Ti bolt kit ready for its introduction!

There was another ceramic rotor other than the Kettle, shown at the Taipei bike show.

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spytech
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by spytech

Ritterview wrote:
The 141 (or is it 146?) gram Spyre mechanical disc looks to be the bee's knees. The Avid BB7 has been the dominant and unchanged mechanical disc for years, and it is great to see new developments. I wonder how much of the Spyre's hardware is steel, and could be replaced with Ti for a further weight savings?


The SLC is 141g for the caliper only, it saves 13g over the standard Spyre. there is still weight that can be saved - the calipers can be made out of aluminum-lithium and a 1 piece monocoque instead of 2 pieces held by screws/bolts. they use these type of calipers in motogp. maybe even full carbon disc calipers, but the heat would be an issue there. i think we will see designs made out of a 1 piece monocoque that are cable actuated in the near future; taking the trp spyre design farther with higher caliper stiffness and lower weight.

I wonder if anyone has used powercordz cables with disc brakes?

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LocoDuck
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by LocoDuck

Perhaps they would be more common for certain races/tour stages where the course has long fast decents. On the flatter routes where less hard braking is required they won't be used as much.
I wouldn't expect to see them on TT bikes too soon.

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maddog 2
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by maddog 2

This has been done a lot on forums recently, and many of the arguments against are either weak or just based on guesswork. I already run discs on my trainer, so have some evidence to work with.

The heat thing is fine, so cross that off. Colnago tested this, with small 140 discs on a big long descent and the heat didn't get anywhere near the critical temp of the hydraulic fluid. Although I admit that many riders can't ride down a hill properly.

The width thing is fine, as frames will be 135mm.

The aero thing is something that people get in a tizz about but disc rims can be made lighter and more aero, and made with carbon without the braking issues that some have, so overall I'd say this probably evens itself out.

The weight thing is probably real, but as the tech catches up there won't be much in it. Di2 was heavier than mechanical when it came out but that didn't stop every rich dude wanting it. So I'd take this with a pinch of salt too.

And as for the UCI... well who cares what they think! Crikey they've been stifling bike design for too long. Sod them. The bike companies need to get something to market and let the punters decide. It's about time the buying public kicked the UCI into shape.

But hey, I'm all for people buying what they want. If you want to stick with cr@ppy rim brakes that's fine. I won't. I ride on real, UK roads. Discs are simply miles ahead of rim brakes for me.


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Ritterview
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by Ritterview

maddog 2 wrote:The heat thing is fine, so cross that off. Colnago tested this, with small 140 discs on a big long descent and the heat didn't get anywhere near the critical temp of the hydraulic fluid.


Uh, not so fast. Tandems most commonly use one disc on the rear, the largest available rotor such as 203 mm, or in our case 220 mm. The disc and rotor get very hot, which is why tandems use mechanical brakes exclusively, as the hydraulic fluid boils. The plastic parts of the Avid BB7 often melt. The brakes fade with heat, and it can be scary on a descent as draws near a failure loop of fading brakes --->increased speed ---> futile braking --> increased heat ---> more fade ---> brake failure.

Tandems are heavier, sure, but our 295 lb team exquisitely aware of heat issues is less a risk than a clydesdale with two 140's or 160's, perhaps with hydraulics, that has gotten the idea somewhere that there are no heat issues and rides the rotors on a long steep descent.

Our clydesdale in this scenario is going to find his Acme road disc brakes are going to get him feeling like Wil E Coyote.

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sawyer
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by sawyer

As it's an opportunity to make money, quite possibly. Though it's not as simple
as "sod the UCI". If pros aren't on them they are less appealing to the market, irrespective
of performance benefits.

Only real performance benefit I can see is wet weather braking. For a sportive type bike in particular
I can a benefit there.

If you need more stopping power in the dry than current main group calipers :

1) you haven't got your calipers/cables/pads/rim set up right

and /or

2) you aren't a decent bike handler
----------------------------------------
Stiff, Light, Aero - Pick Three!! :thumbup:

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maddog 2
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by maddog 2

[yeah, sorry I was on about one-person jobbies]

they are better in the dry too. In my view, based on regular riding, they are better in every way, except they are a tad heavier. Maybe for racing situations then discs don't have an advantage, depending on the course/day/weather etc. but when the tech catches up I suspect this will be pretty close too.

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jmilliron
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by jmilliron

I've got hydro disc brakes on my mountain bike and they're fantastic. Way better then mechanical and rim. One finger braking, awesome for controlling your speed on fast and bumpy descents.

That said, I've got zero interest in them on my road bike. Done a number of wet group rides this winter and my carbon wheels with aluminum brake track were more then adequate. Even in the mountains.

Seems to me like it's a scheme to sell new bikes and components.
2013 Wilier Cento1 SR || 2009 Ridley Crossbow || 2011 Yeti AS-R 5 Carbon

cyclenutnz
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by cyclenutnz

I'd quite like a winter bike (or 'gravel road racer' as winter/touring bikes are now being called) with discs. I was never happy with CX cantis when I used a Cannondale CX bike for training. Trying to find a fork with rake options for road disc is a problem.

However - given that Damon from Cervelo said that aero testing the P5 with discs negated all the superbike design benefits - I have great interest in seeing other people use them for racing. But not for me.

MichaelB
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by MichaelB

Agree with maddog's summary (except tandems).

Have been riding road disc for 16,000km+, and about 8,000 of that with hydraulic discs thanks to a TRP Parabox.

They are the way fwd, it's as simple as that. Most of the naysayers haven't tried a roadie with discs. Whether they get used by racers is irrelevant as they are better in most situations and equal in others.

I reckon the next lot of full hyd groupsets will see the mass release of frame from the big names

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spytech
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by spytech

http://www.bikeradar.com/news/article/s ... ype-36940/

seems like specialized is not wasting any time. i dont like how the prototype levers look. i am content with cable actuated disc for road, but it doesn't mean i wouldn't use hydro, if it was good, easy to use/maintain and light. i just see cable as less problematic.

MichaelB
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by MichaelB

Interesting routing.

Wonder what disc size they are running at the front, as they are using a spacer from the post mount.

Those Zertz things look a bit fugly to me. My taste though.

To me, the 2 things I'm waiting on re the SRAM 22 Disc is the cost and weight. Then I have to decide to get the SRAM, wait for Shimano's Di2 based system or grab the Hywire from TRP when it finally surfaces ???

What a dilemma !!!! :thumbup:

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spytech
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by spytech

Personally i would like to see a CAAD10 with disc brakes and Di2 - that would be a nice everyday trainer for me. high end evo would also intrigue me, but, the canyon prototype has looked the best so far.

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