Chris Froome talks safety concerns of disc brakes in the pro peloton

Does anybody know if there's a time difference between changing a rim brake wheel and one with disks in race conditions? I imagine there's also the opportunity to damage the disk in the rush to get the wheel on? 

And how would neutral service work? Would there have to be a set standard between all manufacturers for size of disk? 

Wow! Usually Pros are apathetic about any change which benefits their sponsors as long as performance doesn't suffer too much, yet many pros, especially those with big money to lose, hate disc brakes! Perhaps it's because they don't like heavy, poorly performing, overly complicated, extremely expensive equipment shoved down their throats. What I think really needs to happen is industry needs to quit pushing these remade mountain bike solutions onto road bikes for profit and develop an appropriate solution to the problems that face ROAD BIKES on PAVEMENT. First, people tell me that discs work better on carbon wheels. I'm here to tell you my Enve's stop better than my aluminum Rims in ALL conditions and don't overheat if properly modulated. And my DA dual pivots are simply amazing, especially where modulation is concerned. As good or better than discs on dry pavement (and yea, I tried discs). So really, were talking about wet rim brakes, which I'll grant don't stop "the same" as discs. Rim brakes will still stop the rim when wet, but the modulation changes radically, extending the time and force to grip (they still have the ability to lock up the wheel), whereas discs lock up right away. And I think there is the problem for top Pro's. Chris probably doesn't want some domestique locking up in front of him without warning. Seems reasonable to me. These bicycle discs aren't ABS like cars and motorcycles became after everybody locked up and crashed, they're the full on, lock-em-up, ancient disk brake technology. You probably can't buy all-wheel non-ABS discs anymore on cars, because manufacturers know they're not safe. Froomey knows he can out-react that domestique now, but if the guy is sprawled in front of him it makes it hard, even if he has discs! And for that he has to pay the price of hauling an extra half pound up a hill? No way! This ain't mountain biking!

It has always been this way.  Even Campagnolo's quick release lever was slow to be adopted.  Disc brakes offer a clear superiority in wet and slippery conditions.  Not so much in dry conditions.  The arguments are fun, but when all is said and done, road bikes of the future will be running discs rather than rim brakes.  The weight and complexity will decrease, and it will open a new avenue of R&D for wheels.  The next great challenge?  Get rid of the damn chain!  C'mon Luddites.... let me have it before you head out for an afternoon ride on your 10 speed steel Ciocc.

Agreed there is an aero penalty - surprisingly not much at low yaw angles apparently,  although that seems to vary with which manufacturer/tester is asked - and that's something which would have to be considered. Certainly I can't see your average top sprinter on a Dutch stage being particularly keen on them. However that's not the same as saying they're 'too heavy' for the pro peleton - which is what I was replying to - and is also not something the article says.

The article assumes that the weight limit woud be scrapped, rather than lowered, because that is the proposal that the UCI are currently considering.

The article makes the point that with the current 6.8kg then there is no weight penalty to discs as pro bikes already need ballast not to be too heavy. From the test results I saw recently (I think on road cc) there IS currently an aerodynamic penalty, although road discs aren't really a fully mature technology yet and there could be all kinds of technical fixes in the future.

I agree that any weight differences between bikes is an addition of extra weights of the discs, the wheels (deep section rims vs shallow 'climbing' rims), kamm tail style frame tubing vs lightweight frames.

You can already see quite a difference between frames designed for different purposes e.g. AX Lightness frame weight 660g vs approx 1Kg for an aero frame.

Wow two pages of comments! Road.cc has its commentators back after the website format change.

And in other news... I love that I am both more experienced at something in cycling, and more reserved in my comments, than Chris Froome by revealing I have ridden a disc-braked road bike and I have no comment about them today

Somehow the pro's think there will be more accidents due to the discs greater stopping power.  Yet discs have better modulation, therefore less chance to a disc that locks up the wheel. Another thing is that since people are different and will have different response times to a situation. So the riders will have different bikes, different brakes, different response times and different levels of modulation to prevent an accident. The riders will always have some accidents which can not be prevented, but disc brakes should help prevent more accidents than they could possibly be the root cause. 

Will the UCI potentially scrapping / lowering the weight limit for bikes mean that disc equipped bikes suddenly become too heavy? 

Funny how some people are lambasting Froome here even though they have never had experience of racing in a professional peloton! 

I imagine his opinion on the dangers of mixed brake use in the Peloton is more educated than most of ours

Allegedly disks will be compulsory as of 2017 in the pro peloton, hence why those manufacturers that don't have them are running around trying to get set up. 

The question is now, why are people being asked by their sponsors to deny this? 

I love this stuff but when I am finished, well I just I hate myself for reading all the way to the bottom. I really want to stop, I do, but the level of nonsense being spouted about the relative merits of two different means of impeding the progress of a bicycle .... I mean I just can't stop, I'm addicted. Can we have a compulsory helmet laws debate again soon please.

I suspect in 2 years time when everybody can use discs if they want in UCI WT races they will be wondering what all the fuss was about.  

1) The one thing you don't do in a tightly packed pelotons is brake hard, it causes crashes when all the bikes have the same type of brakes so adding discs doesn't really appear to change much

2) Modern dual pivots are pretty powerful anyway

3) They can engineer hydraulic discs to give whatever modulation/power they want - they can make them exactly the same as rim brakes. More power = total braking power limited by tyre traction and nobody wants to be in that situation really do they?

'Perform' in the context of disc brakes means they modulate far better than rim brakes. Until tested in a mixed use real-life situation we'll never know whether their is an issues or not (but clearly there won't be an issue. Someone on a disc brake equipped bike can brake in a more controlled manner than with rim brakes. Likelihood is they'll make the peloton safer.)

cyclesteffer wrote:

I think he has a point, I've seen it happen twice to people I know. Both of them had someone drafting who had rim brakes. They had hydraulic discs, braked, and the person behind could not stop as fast as they could. both riders ended up off the bike and in one case with a smashed up rear wheel

In years of riding MTBs in a variety of conditions in close proximity to riders of different abilities,  frames, brake/wheel setups etc, I've only ever stacked it into the back of one where either one of us crashed or one or both of us was acting like a twat (buzzing their rear for example). If you're behind a McLaren F1 in your 20 year old Mondeo you'd be a moron to expect to stop as quickly as they can so you'd be inclined to leave a gap you could stop or at least react appropriately in. Riding behind someone is the same thing. Leave the gap you need. 

Bigringrider wrote:

A Pro doesn’t need discs – but the manufacturers want to sell the next big thing so they’re being introduced to the peloton

Same argument as was used in MTBs. Except it's not true. MTBs are significantly better and safer for the addition of discs and if you EVER see a new MTB without discs it's either a niche, hand built job or a BSO. I, for one, REALLY miss my disc brakes when I'm descending in the wet on my "normal" road bike. The rim brakes, as well set up as they are, are a hazard in comparison to the consistent braking I get from a decent set of hydros. I can handle a skid far more than I can handle not stopping for a junction or a corner. More safety is never a bad thing. 

davel wrote:

They're clearly the right solution for certain applications (eg. cars, or downhill MTB'ing).

I've ridden (and owned) MTBs from fully rigid to 8" downhill sled and they ALL benefit from disc brakes. The ability to pull a brake and have the bike stop should never be underestimated. I don't see a single reason why anyone buying a new road bike who doesn't need full UCI/BC/whatever approval for racing wouldn't want discs. 

I think he has a point, I've seen it happen twice to people I know. Both of them had someone drafting who had rim brakes. They had hydraulic discs, braked, and the person behind could not stop as fast as they could. both riders ended up off the bike and in one case with a smashed up rear wheel

Surely better braking performance means that more riders will be able to avoid crashes in the first place? I really don't buy Chris Froome's argument.

Given that riders ride so close together in the peloton and having fingers on the brake levers is apparently considered a "sign of weakness"  I can't see that having a difference in braking power is going to make a jot of difference to the number of crashes. If the person in front brakes sharply (whatever the braking technology) there is going to be a crash because just the time taken to react and get your fingers on the brakes is too long.

I got used to them pretty quick, I'm sure the pros are every bit as great at riding bikes as I am, maybe better! 

With his crash history I can see why he is concerned

If you’re a bit of a chubber on an ‘endurance/sportive bike’ then I can see the point of discs – weight requires more stopping power - but for anyone sub 70kg, a good set of (and correctly set up) callipers will work just as well in all weather conditions be it alu or carbon rims. A Pro doesn’t need discs – but the manufacturers want to sell the next big thing so they’re being introduced to the peloton to showcase them and the press are all over it too with tag lines that basically read…BUY NEW STUFF OR YOUR PERFORMANCE WILL SUFFER / YOU MAY DIE HORRIBLY!!!

Sounds very much like an off hand comment in response to a question he got asked during the course of a magazine interview. Hardly speaking out about his concerns and safety issues. I'm surprised you've managed to whip up an entire article based on it!

Bill owns a road bike with disc brakes.
Bill also owns a road bike with rim brakes.
Bill modulates his braking effort depending on which bike he is riding and the road conditions at the time.
Bill is smart.
Be more like Bill.

'Nuclear weapons are dangerous' is ambiguous. 

Either it means they can blow things up, so is equivalent to 'bombs are dangerous', and is therefore not a comment particular to nuclear weapons. 

Or it means that you think they are unstable in some way and dangerous to the user.  This is simply an (uninformed) opinion unlikely to generate much consensus, and can be ignored. 

So (nuclear) weapons are dangerous is equivalent to (disc) brakes are brakes.

Surely in this debate, the main topic for discussion should be rider reaction time /delay when using any brake systems, as this is where the main causes of cashes occur ?