2015 disc road bikes from Ridley, Bianchi, Focus, Parlee, Raleigh, KTM, Argon 18, Colnago, Merida and De Rosa

Some of the most interesting disc-equpped road bikes on display at Eurobike

by David Arthur @davearthur   August 31, 2014  

Like it or not, disc brakes on road bikes aren't just happening, they're here right now and available in huge numbers for 2015. Up top is a huge gallery of some of the latest bikes from Eurobike, the world's biggest bike show, but we've picked a selection to give an idea of the different choices currently available.

The majority are carbon fibre endurance bikes, but there are some aero road bikes and even steel and aluminium options too. That most manufacturers are using their endurance and sportive models for introducing a disc road bike is down to several reasons. One is that these bikes are ridden by cyclists who don't need to worry about adhering to the UCI's rules for professional road racing, and that second has to do with chainstay length. 

The space between the rear dropouts has to be wider to accommodate the disc rotor. On a frame with short chainstays, chain line issues can occur. With the longer chainstays of an endurance bike there isn't a problem, but a race bike with short stays the chain line can impact shifting performance in certain gears. Shimano actually recommends a minimum 415mm chainstay length. A typical race bike has chainstays closer to 400m in length - a Cannondale SuperSix Evo  for example has 405mm chainstays. 

Most manufacturers are using regular quick release axles front and ear but some are using thru-axle systems borrowed directly from the mountain bike world, and some are using thru-axles at both ends while some are only using them at the front. Both Focus and Colnago however have developed road-specific thru-axles that aim to be quicker and easier to use. 

The majority of the bikes we saw were running Shimano's hydraulic disc brakes, which is perhaps not really a surprise given the impact of SRAM's long-running disc brake recall which has been in the news this year. We do expect to see plenty of SRAM-equipped models in 2015, quite a few manufacturers are offering them, but most simply didn't have them on their stands.

On the rotor size debate, most bikes were sporting 140mm rotors front and rear, largely because that's what Shimano recommend. We've had some interesting chats with people and there are some saying that 140mm simply isn't large enough to dissipate the heat effectively, even with Shimano's finned Ice-Tech rotors, and that 160mm is a better choice. We'll have to see how this debate plays out. 

Ridley Fenix Disc

Belgian manufacturer Ridley have launched the new Fenix Disc and Jo got to ride it at the demo day earlier this week, and has passed his first ride impressions on it, which you can read here. Ridley have followed the lead set by most other manufacturers and used their endurance road bike platform, a bike built for distance, comfort and cobbles, for their first disc offering. 

Parlee Altum Disc

Parlee lifted the lid on their all-new range of Altum road bikes at Eurobike. This new range of frames replaces the Z5 and will be available in three versions, including a disc model. Unfortunately Parlee didn't quite have time to get the frame built into a complete bike for the show so we'll have to make do with this frameset hanging off the display stand.

This isn’t the first disc road bike Parlee have offered, they launched the Z-Zero Disc last year.

This Altum Disc uses DT Swiss thru-axles front and rear but interchangeable plates allow the rear dropouts to accept a regular quick release setup. The frameset, that’s frame, fork and seat post, will cost £3,299.

De Rosa Corum Disc

Another really interesting bike from the Italian company, this time oversized steel with disc brakes. We didn't see many steel bikes with discs at the show, most were of the carbon variety, so it's good to see a bit of variety.

De Rosa’s Corum is part of the Italian company’s ‘Black Label’ bespoke range of hand-built frames, each can be made to measure and completely customised. 

 

The frame is made from an oversize TIG welded 18MCDV6 tube set with a carbon fibre tapered fork and a 86mm bottom bracket. The frame will take a mechanical or hydraulic disc brake set. It's using regular quick releases and is built up here with an Ultegra Di2 groupset with mechanical disc brakes. 

Colnago V1-r Disc

Colnago showed the C60 Disc but more interesting is the V1-r Disc. You see, most disc road bikes we've seen have been endurance bikes (longer wheelbases, relaxed angles) with disc brakes, but the V1-r is a race-ready aero race bike, and there aren't that many aero road bikes with disc brakes on the market at the moment. We got the full lowdown on the new bike yesterday, which you can read here. 

Like the Focus, the new V1-r uses a thru-axle fork, but pairs that with a regular quick release rear end. We're going to get some more info on the HexLock thru-axle used on the V1-r when we chat to Colnago today. 

Focus Cayo Disc

Here's the new Focus Cayo Disc. Mat was at the launch of this bike so you can get the full skinny on it there. Focus reckon it's the lightest disc road frame currently available with a sub-900g frame weight, and a 380g fork. It uses their own thru-axle standard at both ends. 

Focus have devleoped their own Rapid Axle Technology (RAT) thru-axle system which is insanely easy to use - I shot a short video showing how easy it is to operate, which I'll feature in a standalone article in the coming days. The video is just six seconds long. That's how easy it is to use. You simply open the lever, rotate 90 degrees, and slide it out. 

They've used a 15mm axle because they found they could manufacturer a fork with a single weave of carbon fibre looping around the closed dropout, which apparently wouldn't have been possible if they had used a smaller diameter axle. 

The head tube has been beefed up with some considerable width where it tapers into the top tube, and all the cables and brake hoses are routed through the small plate on the front. 

Merida Ride Disc 7000

Merida first showed a prototype disc-equipped road bike last year but here is the final production model. There'll be several models, this is the Disc 7000 with a Shimano Ultegra group set with 685 hydraulic disc brakes and DT Swiss R24 Spline wheels with 25mm Continental Grand Sport Race tyres. They claim it weighs 7.6kg which is about on the money for a current carbon framed disc bike.

Like the majority of manufacturers, Merida have used their endurance Ride model as the platform for their foray into disc brakes. That’s largely because these bikes aren’t raced by professional cycling teams that have to adhere to UCI rules, and also because most generally have longer chainstays  - for a longer wheelbase - that doesn’t provide the chain line issues that can occur with short chainstays.

Merida have also decided that thru-axles are the way forward, but like Colnago’s V1-r, they’ve only used it on the front. It’s a regular quick release rear axle. The prototype they showed last year had a conventional quick release axle so they've clearly changed their mind along the way, and developed this new fork with a 15mm thru-axle. 

Worth mentioning is the fact Merida have given the frame discrete mudguard mounts, making it a great option for British conditions as a winter trainer or daily commuter.

Raleigh Revenio Disc

Raleigh's Revenion Disc uses an aluminium frame with the same geo as the regular Revenio, but adds disc brakes. They've opted for traditional quick release axles and unlike the majority of the bikes we've seen, they've placed the rear disc caliper on the outside of the seatstay. There'll be a range of bikes including this model with TRP Spyre mechanical discs.

The Revenio bikes have a more relaxed geometry than standard road bikes so you get a fairly upright ride position. The on-trend 25mm tyres used across the range are designed to provide a bit more comfort and reduced rolling resistance.

Taps into the versatily that we like on road bikes, with rack mounts.

 

Bianchi Impulso Disc

A lot of the disc-equipped road bikes we've seen feature carbon fibre frames, but there are several aluminium, and even steel, frame options for those that don't want, or can't afford, a carbon model. This is Bianchi's new Impulso Disc and it looks really good. It uses the same C2C geometry as found on the Infinito CV so the ride should be good. 

There's no hydraulic disc brakes though, instead they're going with Avid's BB7 mechanical discs. 

Those Italians do like an anniversary. 

KTM Revelator

KTM do disc brakes on road bikes as well, giving their Revelator model the disc treatment for 2015. They're using a 15mm front axle and also borrowed directly from the mountain bike world is the 142mm wide rear end with a 12mm axle.

KTM have chosen to give the new bike thru-alxes front and rear

It's a pretty smart looking bike it has to be said, is available in a range of colour options and this integrated seatclamp is a nice detail. 

Argon 18 Krypton XRoad

The brand new Krypton XRoad from Canadian manufacturer Argon 18 is their new road disc offering, but they've pitched it as far more than just a road bike, and describe it as being ready to tackle any terrain. So think 'gravel' bikes and that sort of influence, which means big tyre clearance and the sort of geometry that should make it stable when handling over a bit of rough stuff. 

De Rosa Idol Disc

The new Idol now available with or without disc brakes, here is is the discs. Full carbon fibre frame and fork, Shimano's Dura-Ace Di2 groupset with hydraulic discs, 140mm rotors front and rear, and regular quick release axles. 

 

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We'll be updating this article with a lot more disc-equipped road bikes so be sure to tune back in for more. 

Click here to read all of our stories from Eurobike 2014 - the world's biggest bike show.

47 user comments

Latest 30 commentsNewest firstBest ratedAll

Can someone develop a plastic hat that doesnt encourage bees to sting my head please, thats an actual problem that needs fixing.
Braking on a race bike isnt.

posted by IanW1968 [230 posts]
1st September 2014 - 12:34

2 Likes

localsurfer wrote:
I'd love to know if pro riders really want discs. They'd never say, of course, because sponsors, but whenever I've ridden a closed-road sportif it's noticeable how little I use/need brakes with no traffic or traffic signals/roundabouts to get in the way. I assume pro riders use them even less.

But they're heavier, make wheel changes more awkward, different standards.. would a racer want this?

Here's a small but interesting cross section of views

http://velonews.competitor.com/2014/08/bikes-and-tech/stopping-progress-...

Over the recent years there have been quite a few articles on there about discs in CX and on road bikes, worth a look.

fukawitribe's picture

posted by fukawitribe [1233 posts]
1st September 2014 - 13:00

0 Likes

So, I'm starting to be convinced that hydraulic discs on a road bike might not be as crap as the cable ones on my hybrid and CX.

What's that? The industry hasn't worked out what sort of hub axle I'll need, potentially meaning I'll be stuck with the cycling equivalent of a daisy-wheel typewriter? You bunch of absolute idiots. The RAT system looks good. Let's all do that.

http://xkcd.com/927/

Boardman CX Team '14 | Cannondale CAAD8 '12 (written off, SMIDSY) | Scott Sportster '08

Gizmo_'s picture

posted by Gizmo_ [1224 posts]
1st September 2014 - 13:01

2 Likes

"Raleigh's Revenion Disc combines the same carbon frame as the regular Revenio, but adds disc brakes. "

Am I missing something here? The pictures sure look like a welded frame

posted by paulrbarnard [182 posts]
1st September 2014 - 13:34

0 Likes

I'm happy to review the De Rosa Corum any time you feel like it. No, really. You just have to ask.

Bez's picture

posted by Bez [523 posts]
1st September 2014 - 14:04

0 Likes

In fact, given that's awful lot of bikes that you clearly need to review, I'm, like bez, happy to help out. Seriously.

posted by Al__S [874 posts]
1st September 2014 - 15:34

0 Likes

I don't think the weight argument is really valid. I'm sure when rim manufacturers no longer have to worry about braking surfaces and heat flow the rim weights will decrease, so they could be even faster than conventional setups!

posted by AdyM [12 posts]
1st September 2014 - 15:40

0 Likes

There's some interesting comparisons being made to mountain bikes here. It does make one wonder whether some of you have actually ridden an mountain bike... Wink

Quote:
If discs don't have a great advantage over rim brakes off road...

They do. Massively. A separate surface for braking on, specifically designed for purpose? Away from the ground? Less prone to buckling? Yes please! Let's be clear here - the latest mountain bike brakes are nothing short of amazing.

Quote:
The thing about MTB is you can build up a lot more speed.

I realise that this is now taken out of context, but most mortals won't get over 40mph on a mountain bike - the terrain prevents it. However descending from an Alpine pass on a road bike is a different kettle of fish...

The two major problems I see with discs on performance road bikes (and not tourers or CX bikes - I think discs would be great there) are that 1; bikes will be have to be redesigned to fit and support disc brakes (not a massive problem, to be fair) and 2; brakes will be too powerful. A road tyre has a very small contact patch - I would be concerned that, certainly in the rear, over-braking / sliding out could be an issue.

Me? Behind the bike sheds? With a young lady and a tube of grease? With my reputation?

Pimpmaster Jazz's picture

posted by Pimpmaster Jazz [17 posts]
1st September 2014 - 15:58

3 Likes

don't actually give a toss if 'the peleton' will use them or not. I'm about as far removed form a pro rider as I am from a dolphin. I've been using discs on a CX bike for commuting for the past 18 months, and I will never buy another bike without them - so that's at least one bike I will have to replace. I welcome the fact that the big manufacturers are starting to offer discs on their bikes; it's all going to get easier and better from now on.

posted by pz1800 [24 posts]
1st September 2014 - 18:31

2 Likes

PJ
I'm not convinced they are even more powerful, definitely in wet or muddy conditions that you may regularly experience on a commuter or tourer.
But in the dry on a sporting race bike, rim brakes benefit from much greater leverage enough to lock either wheel and skid or endo without trying too hard.

Happy to have discs available but I hope rim brakes stick around for the appropriate applications.

posted by IanW1968 [230 posts]
1st September 2014 - 19:57

1 Like

Well I rode a hundred mile charity sportive on Sunday, it started off sunny which was fine with rim brakes, nearly new brake pads and clean rims. Then it rained, when approaching junctions, some of them downhill I had to pull extremely hard with all my fingers wrapped round the brake levers it took a worrying amount of time for the brakes to bite and slow me down. After years of riding disc brakes on mountain bikes I never worried about braking and could happily brake in all conditions predictably going back to riding road bikes with rim brakes can be frightening.

I welcome disc brakes on road bikes, they are safer, being predictable in all conditions, you don't have to cripple your hands gripping the brake levers in the hope you will stop and there is less wear and tear on the rims, also disc pads seem to last a heck of a lot longer.

There are no downsides to disc brakes on road bikes in my eyes and unless you are racing and have to abide by uci rules. I find my riding much more enjoyable when I'm not shi***ng myself trying to stop on wet rims our for cars pulling out in front of me but each to their own.

It rains at weekends too or do most rim brake advocates only ride when its guaranteed not to rain? There are no guarantees with BBC weather forecasts, it was supposed to be nice on Sunday! Admittedly I do ride to work every day too so would really benefit I regularly struggle to stop the bike quickly in the wet if drivers pull out in front of me. And the thing about tyre contact area on the road is crazy, yes you could lock up your wheels and they could skid out from under you buy you can do that with any brake with enough force. You'll adapt that's what people do, you'll apply less force but get greater breaking performance and after years of riding the lack of death grip on the brakes levers will reward you with non crippled fingers.

More discs, sooner and cheaper please!

posted by herrow [13 posts]
2nd September 2014 - 7:17

3 Likes

As Gizmo comments, the industry "seems" incapable of settling on a road bike standard for thru axles. I very much suspect this disagreement is superficial, the true reason is to launch generations of "daisy-wheel" disk brake road models before settling on a standard. The consumer will be milked.
Furthermore, I conclude with some bloggers that many road bikers never experienced the benefits of disk brakes, available to MTBers for at least 10 product generations, evolving into a totally mature technology. Again, professional road biking lives in a world of its own, ruled by a UCI which hinders bike design progress in the name of "leveling the field" but turns a blind eye on the disproportion of sponsors' budgets and worse...
The launch of of so many disk brake road models (warts and all) probably settles the argument in favour of disk brakes for road use. The next hurdle is to force manufacturers to offer wider tire clearance to make road bikes more universal and... faster (it is no coincidence that professionals are migrating from 20-23mm tires to 25mm now, probably 28mm in the future).

The entropy of the universe increases constantly. Carpe diem.

posted by noether [96 posts]
2nd September 2014 - 8:11

2 Likes

Don't forget, once the brakes have stopped the wheels turning, whether and when your bike stops moving forward is entirely down to the grip between your tyres and the road surface.

In dry weather, what makes a good brake is not its ability to stop you moving forward - that's easy. It's the quality of control or modulation the brakes give a rider over their speed. In road racing, stopping a bike is primarily a safety issue not a racing issue. In a race, predictable, direct and precise control of speed is very important and good brakes can make a big difference to a race's outcome, allowing a rider to race faster and with more confidence.

The disc brake debate, with it's various often conflicting aspects, seems confused. If safety is your priority, and for most bike users it has to be, then disc brakes seem to win the case. This is because most bike users, riding on public roads, with cars and often in rain, must surely benefit from the fact that disc brakes will very quickly stop the wheel rotating however heavy the rain. Of course, the question of whether you and your bike stops or not is another matter.

I have used all kinds of brakes over the years on various bikes. These have included Campagnolo Deltas, Scott Self Energising brakes, U-brakes, side pulls, centre pulls, cams, V-brakes and most recently disc brakes. All have been effective stoppers - some extremely effective. Their modulating qualities however have varied widely. So it is modulation that is the Holy Grail of brake design, not stopping. In dry weather I have found modulation in good disc brakes excellent, but not noticeably better than good rim brakes.

Then there are questions of servicing (which raise issues of safety), speeds of wheel change particularly in pro racing and standardization. This last issue of standardization raises further questions of how bike manufacturers can damage their own industry and therefore the interests of cyclists by not standardizing their (so-called) innovations. We have seen a lot of this recently.

For me, it seems on balance and if the question of competent and reliable servicing can be dealt with, disc brakes are the best option for most people because most people who ride bikes ride them on public roads, in traffic and often in the rain.

For those that race (as I used to), or who use a road-racing bike for fun and not commuting/shopping/nipping round the corner/carrying the kids, etc, then I still need to be convinced that disc brakes aren't just another thing the bike industry hasn't conjured up to convince people they need to throw away what they have spent their hard-earned money on just in order to buy something else. Let's face it, a real road-racing bike hardly ever needs to stop.

posted by Daddylonglegs [13 posts]
2nd September 2014 - 10:50

1 Like

Daddylonglegs wrote:
For me, it seems on balance and if the question of competent and reliable servicing can be dealt with, disc brakes are the best option for most people because most people who ride bikes ride them on public roads, in traffic and often in the rain.

For those that race (as I used to), or who use a road-racing bike for fun and not commuting/shopping/nipping round the corner/carrying the kids, etc, then I still need to be convinced that disc brakes aren't just another thing the bike industry hasn't conjured up to convince people they need to throw away what they have spent their hard-earned money on just in order to buy something else. Let's face it, a real road-racing bike hardly ever needs to stop.

your last two paragraphs are pretty contradictory. the vast majority of people who use a road racing bike for fun will encounter the same weather and traffic as commuters and shoppers. I simply don't see the distinction.

A real road-racing bike hardly ever needs to stop? that simply doesn't make *any* sense. I take my real road racing bike and fling it down cheddar gorge at 40mph+ on a fairly regular basis. the ability to stop is quite important. even more so the ability to regulate your speed with minimum effort, which is what disc brakes are so good at.

Dave Atkinson's picture

posted by Dave Atkinson [7834 posts]
2nd September 2014 - 10:54

0 Likes

Dave Atkinson wrote:
Daddylonglegs wrote:
For me, it seems on balance and if the question of competent and reliable servicing can be dealt with, disc brakes are the best option for most people because most people who ride bikes ride them on public roads, in traffic and often in the rain.

For those that race (as I used to), or who use a road-racing bike for fun and not commuting/shopping/nipping round the corner/carrying the kids, etc, then I still need to be convinced that disc brakes aren't just another thing the bike industry hasn't conjured up to convince people they need to throw away what they have spent their hard-earned money on just in order to buy something else. Let's face it, a real road-racing bike hardly ever needs to stop.

your last two paragraphs are pretty contradictory. the vast majority of people who use a road racing bike for fun will encounter the same weather and traffic as commuters and shoppers. I simply don't see the distinction.

A real road-racing bike hardly ever needs to stop? that simply doesn't make *any* sense. I take my real road racing bike and fling it down cheddar gorge at 40mph+ on a fairly regular basis. the ability to stop is quite important. even more so the ability to regulate your speed with minimum effort, which is what disc brakes are so good at.

I'm not sure they are Dave, but maybe they need explaining better and maybe the last line was a bit flippant. What I'm saying is that it's 'horses for courses'. If you're pulling the bike out of the garage, nipping round the corner, through the traffic and back again for fifteen minutes, or riding to work every day through unpredictable rush hour traffic with packed panniers or a rucksack in the rain, it seems to me discs are ideal because some of the care and concentration required to use rim brakes in wet weather is lost in these situations.

But if your other bike is a road racing bike (not an audax or a tourer or sportive bike), then I'm not sure disc brakes are that relevant. I understand your point that if you're flying down Cheddar Gorge you want good brakes, but decent rim brakes are good brakes. And their ability to stop you is as good as discs, which is what I was arguing. I've been down Cheddar on bikes with disc brakes and rim brakes and the thing that's slowed me down isn't the question of how good my brakes are, but fear of whether I'll get round the bends at the bottom. There seems to be this utter conviction and assumption that in dry weather on road bikes, disc brakes not only stop you quicker, but have better modulation. I'm not sure either of these are true.

When I'm out on my road racing bike and I'm caught in the rain (I try to avoid this!), my brake's stopping abilities are certainly less effective, but the way I choose to use my road bike means I'm either on my own or with a few other riders, on roads fairly or very free of traffic. I am able to pay attention far better to what's going on in these situations, because less is happening. It seems to me this lowers any perceived risks dramatically.

If someone buys a bike designed to be raced on roads and circuits, why then use it inappropriately in teaming rain and heavy traffic and then look for solutions to the inevitable problems this throws up? Why not just buy or design a bike more appropriate for the use? If I buy a Ferrari, do I get the suspension raised so I can get down the local farm track?

A road racing bike is a road racing bike. It has quite limited uses beyond that. Racing round a tight city centre circuit requires excellent braking modulation, but very little need to actually stop - assuming the bloke in front stays upright. Not that rim brakes won't stop you perfectly well. That's why I think disc brakes on road racing bikes is an expensive waste of time and disc brakes on most other types of bike isn't.

posted by Daddylonglegs [13 posts]
2nd September 2014 - 18:49

3 Likes

For a racing pro I can see how disc brakes would be a bad thing - wheel changes will be slower and the current proliferation of standards will mean neutral support vehicles become almost impossible.
For everyone else then discs are going to be better 99% of the time. The one percent being non-pro racers who also have the same challenge.
People talking about the weight penalty are probably over-egging the problem there. I recently converted my commuter to having a hydraulic disc front brake for a total weight increase of 200g. That really ain't a lot (especially as my fully loaded bike weighs about 56lb).
The sooner they sort out a standard axle approach then the sooner all the non-racers can move on to better braking.

posted by blinddrew [37 posts]
2nd September 2014 - 21:24

0 Likes

Dave, you're not racing though. If you're competing everything becomes relative and what matters is how your equipment compares to those you're competing with. You could equip a peloton with brakes made of sponge and the racers would adjust to the limit. Indeed, judging by my 1970s road bake with Weinmann lightweight brakes, that's already been done! Smile

As to whether better brakes make people safer, there is evidence in other contexts that this may not be true. See risk compensation, and studies done on the introduction of ABS to taxi fleets in Germany (iirc Bremen).

Give people better brakes, and they may adjust and simply brake later, taking the same perceived amount of risk.

posted by Paul J [808 posts]
2nd September 2014 - 22:38

0 Likes

IIRC this would affect more than the 'pro peloton'.
If you're racing at Cat4 level your bike needs to meet BC rules, which are a subset of UCI rules? So you'd not be able to race on discs then.

Just an assumption though, I'm aware someone may come and comment and had done Cat 4 race at XYZ running discs.
Just if that is applicable then it's another reason some people aren't considering them.

glynr36's picture

posted by glynr36 [638 posts]
2nd September 2014 - 23:07

0 Likes

IanW1968 wrote:
PJ
I'm not convinced they are even more powerful, definitely in wet or muddy conditions that you may regularly experience on a commuter or tourer.
But in the dry on a sporting race bike, rim brakes benefit from much greater leverage enough to lock either wheel and skid or endo without trying too hard.

Happy to have discs available but I hope rim brakes stick around for the appropriate applications.

And the world is flat and the moons made out of cheese, ffs just how much evidence do you need ????

posted by yespsb [10 posts]
3rd September 2014 - 9:53

0 Likes

yespsb wrote:
IanW1968 wrote:
PJ
I'm not convinced they are even more powerful, definitely in wet or muddy conditions that you may regularly experience on a commuter or tourer.
But in the dry on a sporting race bike, rim brakes benefit from much greater leverage enough to lock either wheel and skid or endo without trying too hard.

Happy to have discs available but I hope rim brakes stick around for the appropriate applications.

And the world is flat and the moons made out of cheese, ffs just how much evidence do you need ????

IanW, it doesn't matter how much extra power a brake has once it has stopped the wheel turning. You could put truck brakes on a bike, but in real terms they won't be any more powerful than basic side-pulls once they've grabbed the wheel and stopped it going round. All their potential extra power will be wasted once they've stopped the wheel turning. All this talk of brake 'power' is mostly badly thought-out nonsense. This extra wasted power from a brake usually means extra weight from the extra (over)engineering required. Manufacturers love to over-engineer products because it helps sell stuff to people who aren't paying the subject enough attention beyond listening to the marketing.

posted by Daddylonglegs [13 posts]
3rd September 2014 - 19:29

0 Likes

glynr36 wrote:
IIRC this would affect more than the 'pro peloton'.
If you're racing at Cat4 level your bike needs to meet BC rules, which are a subset of UCI rules? So you'd not be able to race on discs then.

Just an assumption though, I'm aware someone may come and comment and had done Cat 4 race at XYZ running discs.
Just if that is applicable then it's another reason some people aren't considering them.

if the commissaires are doing their job properly, you shouldn't be able to race at your local cat 4 on discs

Dave Atkinson's picture

posted by Dave Atkinson [7834 posts]
3rd September 2014 - 20:47

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Daddylonglegs wrote:

IanW, it doesn't matter how much extra power a brake has once it has stopped the wheel turning. You could put truck brakes on a bike, but in real terms they won't be any more powerful than basic side-pulls once they've grabbed the wheel and stopped it going round. All their potential extra power will be wasted once they've stopped the wheel turning. All this talk of brake 'power' is mostly badly thought-out nonsense. This extra wasted power from a brake usually means extra weight from the extra (over)engineering required. Manufacturers love to over-engineer products because it helps sell stuff to people who aren't paying the subject enough attention beyond listening to the marketing.

as i've said many times, and am happy to say again and again, the absolute power of disc brakes isn't what makes them better. what makes them better is that the power is consistent, and easier to apply, and not affected by the conditions, or what your rims are made of.

talking to liam glen, who came in to the office today, was interesting. he's been racing on the continent this year. he's all for discs: better that than trying to stop yourself by ramming your hood into the bloke in front's arse when it's pissing down and your carbon rims won't stop you, at all. that was his take Smile

Dave Atkinson's picture

posted by Dave Atkinson [7834 posts]
3rd September 2014 - 20:52

1 Like

Does anyone know the weight difference between a disc-equipped carbon wheel + frame and a comparable rim-brake-equipped aluminium wheel + frame?

One appeals of discs is the ability to make carbon wheels less shit at braking in the wet. However, this obviously comes with the penalty of adding the weight of the disk and other necessary bits to the carbon wheel, somewhat reducing the advantage of a carbon wheel in the first place.

It's a bit of an awkwardly open question, but does anyone have any light to shed on it?

posted by Quince [372 posts]
3rd September 2014 - 21:31

0 Likes

Dave Atkinson wrote:
glynr36 wrote:
IIRC this would affect more than the 'pro peloton'.
If you're racing at Cat4 level your bike needs to meet BC rules, which are a subset of UCI rules? So you'd not be able to race on discs then.

Just an assumption though, I'm aware someone may come and comment and had done Cat 4 race at XYZ running discs.
Just if that is applicable then it's another reason some people aren't considering them.

if the commissaires are doing their job properly, you shouldn't be able to race at your local cat 4 on discs

I thought so.
Meaning it affects far more than the 'pro peloton' many keep quoting.
Anyone racing then won't be paying attention I imagine unless a disc bike becomes another n+1 bike.

glynr36's picture

posted by glynr36 [638 posts]
3rd September 2014 - 22:00

0 Likes

Quince wrote:
Does anyone know the weight difference between a disc-equipped carbon wheel + frame and a comparable rim-brake-equipped aluminium wheel + frame?

One appeals of discs is the ability to make carbon wheels less shit at braking in the wet. However, this obviously comes with the penalty of adding the weight of the disk and other necessary bits to the carbon wheel, somewhat reducing the advantage of a carbon wheel in the first place.

It's a bit of an awkwardly open question, but does anyone have any light to shed on it?

there's a few factors at play. deeper rims (30-50mm) are more popular at the moment and there's a feeling that some material could be removed if a brake track isn't required. however, carbon's not great at dealing with the kinds of forces you get with clincher tyres pushing against a rim, so the necessity of a braking thickness might not be the limiting factor.

weight at the rim is much more important in terms of wheel momentum than weight at the hub, so gains there have more effect. It's still a bit early to say though how light disc wheelsets can be. most are sticking with 24 spokes and i haven't seen any go under 20, save for lightweight's prototype and that's a very different beast.

the lightest disc wheels we're currently seeing are around the 1,400g mark. there's plenty of alloy wheels around that weight. disc hardware carries a penalty over rim brakes of 200-300g.

Also, the main reason people switch to deep section carbon wheels is the aero advantage, not the weight. and discs aren't quite as aerodynamically efficient as rim brakes.

this doesn't really answer your question Smile

Dave Atkinson's picture

posted by Dave Atkinson [7834 posts]
3rd September 2014 - 22:13

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As an aside, there seems (to me) to be a feeling among many people who are against discs that they're not the finished product and it's all happening too quickly without common standards for things like dropouts.

'twas ever thus though. The same thing happened with MTBs, we had some *really* bad brakes for years, and two competing mount standards for a full decade. and clincher tyres took a while to settle down too, back in the day. the first iteration of a new technology isn't ever perfect. road discs won't be either. that doesn't mean it's not a path worth pursuing.

Dave Atkinson's picture

posted by Dave Atkinson [7834 posts]
3rd September 2014 - 22:20

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Thank you! It's filled some holes in my curiosity, so I'm glad about that! I've just bought a shiny new race bike (with rim-brakes), so I shouldn't have to make any big financial bicycle decisions for a while (n+1 be damned).

Hopefully by the time I do have to buy a new bike, the dust will have settled a little, the brake-tribes of the internet will have become a less vociferous and the choices a little clearer.

I can't help find the issue interesting though... Let's see what happens, eh? Hooray bicycles!

posted by Quince [372 posts]
3rd September 2014 - 23:10

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The cable discs on my Saracen Hack give me a lot more confidence in the wet - I know the stopping will be consistent regardless and I won't be squeezing the lever praying that I'll stop like I might be with even good calipers.

I actually think its the hydraulic element that makes for good modulation. My Magura HS33 hydraulic rim brakes felt great, as have the the hydraulic discs on every mountain bike I've had for the last 10 years. No cable drag / stretch etc. They just feel smoother and more easy to modulate.

posted by mtbtomo [162 posts]
3rd September 2014 - 23:11

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Gizmo_ wrote:
So, I'm starting to be convinced that hydraulic discs on a road bike might not be as crap as the cable ones on my hybrid and CX.

What's that? The industry hasn't worked out what sort of hub axle I'll need, potentially meaning I'll be stuck with the cycling equivalent of a daisy-wheel typewriter? You bunch of absolute idiots. The RAT system looks good. Let's all do that.

http://xkcd.com/927/


You seem confused. Only one thru-axle standard (at each end) is in use on road bikes: 15 mm and 142 x 12 mm. Referring to RAT and the like as different standards is equivalent to distinguishing between external and internal cam QRs in the same way.

posted by Ham-planet [108 posts]
23rd September 2014 - 9:49

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Ham-planet wrote:

You seem confused. Only one thru-axle standard (at each end) is in use on road bikes: 15 mm and 142 x 12 mm. Referring to RAT and the like as different standards is equivalent to distinguishing between external and internal cam QRs in the same way.

yes, you need to think of the axle as part of the fork, not part of the wheel. the different 15mm variants all use the same hub.

Dave Atkinson's picture

posted by Dave Atkinson [7834 posts]
23rd September 2014 - 10:51

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