Why dont road bikes have disc brakes????

What has expense got to do with anything?

Well, it tends to feed into cost-effectiveness. If you aren’t racing, why would you chase negligible performance benefits at escalating cost? Most recreational riders have a budget.

Let us assume that you are correct that disc brakes could be brought in on the same weight, but let us also assume (as you do) that they would be more expensive.

Therefore, as a recreational rider, for a given budget, I can have a bike with adequate brakes and a very very light frame, or a bike with brakes that are more powerful than is strictly required at the cost of a heavier frame. And, to cap it all, my bike won’t be race legal. I know which I am going to go for. Your answer may be different.

I don’t care, when road racers have tiny little disc brakes I shall have one with tiny little disc brakes, just as I have a mountain bike with disc brakes these days. But I can understand why it isn’t a priority for designers and manufacturers, or, indeed, almost anyone except you.

🙂

You constantly go on about lighter rims – but my cx wheels have rims which weigh about 350g and they’re nothing special, Reynolds carbon sprint rims weigh about 200g. How much lighter exactly do you envisage making them disc specific would make them?
You do realise that a lot of people now ride 35-50mm deep rims for aero benefits, so how would you make these lighter?
For commuting bikes discs are fine but for fast, lightweight road bikes I still don’t think discs are at the right level of technology, weight or useability yet. Maybe in 5 years they will, but not now.

No, sorry, still not having it. The only real obstacles seem to be rules, stuffiness, and fashion.

but disks are an answer to a problem that doesn’t really exist.

Q: are current road brakes powerful enough to overcome the grip of a 23c tyre and does their use enable the user to accurately modulate available braking power?

A: yes.

Q: are disk brakes needed on road bikes?

A: no.

I remember the debate over suspension for MTBs, plenty were convinced that whilst a couple of firms were pushing it it had no real benefits and would not stand the test of time.

There are plenty of punters out there who will buy something because it is different or perceived more “hi-tech”. Marketing dudes know this.

Only a fool would say that high-end roadie bikes will NEVER have disc brakes.

Q: Are discs better than rim brakes?

A: Yes

Q: If you could have discs and suffer no weight or cost penalty would you have them?

A:

Q: Can pigs fly?

A: No

Q: If pigs could fly, would that be AWESOME?

A: Hell YES!!!

🙂

Thanks for the replies and answers… 🙂

TBH MTBs do not need discs either…cantis or vs are perfectly acceptable. More sophistication and technology for us to part with our well earned dosh!

Just been Reading through this thread with much amusement. Why, exactly is a road bike only a racing, and anything else with skinny tyres and drop bars isn’t a road bike? Sorry, I’m confused. Druidh’s Sutra is a touring bike. It’s for riding distances on the road. It has skinny tyres and drop bars. That makes it a road bike. To say otherwise makes you a snob. I also have a Sutra, with one gear, aero bars and bar-end levers with cross-top levers as well. It’s a road bike. It’s not a tourer, it’s not a cx bike, and it’s most definitly not a mountain bike. It does, however have discs. And a Brooks Swift Ti saddle. ;0)

Cant be bothered to read all this, but I presume somone has mentiond because there not needed.

Erm, you’re comparing top-end, ultra lightweight road bike components, with MTB ones. Hardly fair.

Can’t be bothered any more.

Hurray

my road bike has got disc brakes. weighs 18lbs

@steve austin.

Got any pix.

I’ll bet all roadies would have disc brakes if they were allowed at the TDF or something.

I’ll bet all roadies would have disc brakes if they were allowed at the TDF or something.

No, they wouldn’t.

I’ve been running Avid BB7 discs on my commuting/touring/winter training road bike for the last 5 years. No problems with handling or braking control under normal conditions, in snow, on ice or on fast, long Alpine descents with full camping gear. I usually use 28mm touring tyres, but have run 25mm as well.
I chose to use discs for my utility road bike bike for easier adjustment and maintenance (cf V-brakes or cantilevers) and to avoid the serious rim grinding that occurs with regular winter commuting. I wouldn’t go back to rim brakes for this sort of application.
I wouldn’t use discs on my road racing bike, because of the performance penalty imposed by a beefier fork and added kit weight. Good quality sidepulls are excellent, and currently the best solution for a fair-weather race bike.
So, to cut a long story short, discs work very well for some road bike applications, but they aren’t widely adopted because the range of suitable brakes, frames and forks is currently limited.

gingerflash

“make smaller, lighter less powerful ones for the road that give as much stopping power”

Less powerful but with as much stopping power? Eh?

Not well worded perhaps. Gist was, as I suspect most understood, max stopping power is the power needed to lock a wheel. Both brakes have enough. Any more is power won’t stop you any quicker so can’t really be called stopping power just wasted over-capacity and comes at the expense of weight and feel / modulation.

UCI regulations state that a bike has to be heavier than a certain weight. However, many bikes are sold well under this weight and many of the want to be racers are very happy to get their bikes under this weight. If disk brakes gave such a great advantage to people, then you’d be seeing disk brakes at every sportive across Europe.

I really wonder how these small lightweight disks are going to cope with stopping a bike travelling at high speeds down an alpine descent?

Hybrid bikes travel at very different sort of speeds than race bikes so disks on these are a different question. I still think it’s done for image, just as cheap ‘mountain bikes’ that you get in Tescos have suspension for looks, rather than function.

100 posts of mostly complete rubbish 🙄

Trolltastic 🙂

101

Road bike brakes are cack – fact. If you are cruising to a halt in the dry, they work. But try a really steep South Wales hill leading directly into a roundabout in the wet, and you will see what I mean. I’ve got 105 calipers with aftermarket blocks and the idea that anyone could compare them to XTR discs is laughable. The Tektro Vs on my commuter are almost as good as discs and about a million times better than the 105 caliper – wet or dry. Come round my house and try it out if you don’t believe me.

molgrips, what do you reckon to little discs, then? Do you think they would be a big improvement?

The number of times I’ve seen TDF riders go over the edge on tight bends, I can’t help thinking better brakes might be an idea. Speshly for bigger riders.

They go over the edge on tight bends because they’re attempting to go round them at about 40mph – nothing to do with not having disc brakes.

molgrips: your brakes aren’t set up right then. I’ve got Dura-Ace calipers on my road bike and they’re more than enough. In fact when Shimano remodelled Dura-Ace they obviously gave it to the pros for a year before it was available to the general plebs and the feedback was that they were TOO powerful. So Shimano cut out a little bit of the rear caliper to make it flex more and make it LESS powerful.

Introducing yet another bloody “standard” to an industry already awash with God knows how many different “standards” for all sorts of things is the last thing on earth that anyone needs.

aP: the footage I’ve seen suggests that they failed to slow down sufficiently for the corner. Whether that’s down to crap skils or shyte brakes, I don’t know.

Road racing bikes WILL one day have little disc brake systems. It’s only a matter of time.

Yes dear 😮

the footage I’ve seen suggests that they failed to slow down sufficiently for the corner. Whether that’s down to crap skils or shyte brakes, I don’t know.

Or could it just be the fact that they’re tired cos it’s the middle of a 3 week stage race, they’ve already done 100+ miles that day at speeds you and I can only dream of doing and they’re hurtling downhill on a road they’re not familiar with surrounded by cars, motorbikes, crowds, other riders, there’s a TV helicopter or 3 clattering close overhead and they’ve got their director sportif and race radio giving them information in their earpiece. It’s enough to distract even the most hardened of pros and it’s got f*** all to do with the brakes!

Ok then.

I think one of the biggest advantages of the disc brake systems is greater modulation of braking, After switching to disc on the mountain bike, remember, I had better brakes and skidded less because of more braking control, modulation. Road bikes would also benefit from better braking modulation not just the greater braking power! This ones for you Tod!!!

my 105 brakes work amazingly. in the afternoon they get super powerful cos the pads get hot and tacky.

(I live in Oz BTW, may not relate to lancashire on a wet wednesday in janurary).

How about drum brakes? Like those Sturmey Archer ones?