Disk brakes for road race bikes. yes/no/why?

[kiwirider]

I've still got a foot in each camp ...

Part of me thinks that - as a couple of people have said - dual pivot rim brakes give you all the braking that you need on a roadie. Mind you, in saying that, back in the day I used to race on a bike that was equipped with Campag delta brakes - so even the worst of modern braking performance is a step up from that!! (It's amazing how we can forgive a lack of function when the aesthetics are so good ...)

On the other hand ... I ride discs on my MTB and definitely appreciate the step up that they gave from v-brakes. And I'm not talking about power - it's modulation and certainty of operation that instills the confidence to brake later - and in turn gives more speed.

I also had a cross race on a disc equipped bike during last season. My buddy has a Salsa Las Cruces with Avid cable discs (the ones designed for use with Ergo/STI/Doubletap). I used it on what has to be the most "roadie" of the courses that we use during the season - wide open parks with a few corners ... and about 5cm of snow for good measure. Despite the bike being a last minute change, different gear to mine and slightly wrong set up (including not running "moto-style" brake set up), I felt that there were the same sort of noticeable, significant braking improvements over a standard canti bike.

I realise that neither of the two disc comparisons are a road situation, but I think that I can see the argument for disc brakes making it over to road bikes. If they do though, I'd say no need to go beyond cable - the modulation and braking power are fine for road - which has much lesser braking demands than dirt riding.

Does that mean that I'd buy them?? Probably - but only because I know that at some stage I'll put discs on my cross bike and it'll make sense to have the ability to swap wheels between cross bike and roadie. Other than that, nah ... I'd just stick with the rim brakes ...

 

[DirtyWorks]

In order for disk brakes to "be here sooner than [Terminator] thinks" on road bikes, Miss Bossy Pants, there would have to be a problem with the current caliper/rim system. Otherwise, why would they switch? It's not like they don't have the technology right now. Right?

As much as I wouldn't bother with disc brakes on the road, I see some opportunities for discs on the road.

1. It looks like car/motorcycle brakes.
2. Places where it regularly rains and the area has a diverse cycling population will probably find a willing client base. Probably is an expensive gamble though.
3. The industry loves to sell new stuff that's entirely different than the old stuff.
4. Most of you guys are talking about a 1-to-1 conversion from MTB. The product that's successful will not be like a MTB product. For example, a cable actuated product is completely viable on the road.

These observations are coming from a guy shouted down in the 'cross group for disregarding discs in that specialty. I still think they are useless in most 'cross racing, but there's a viable niche that doesn't race on road and 'cross. Will we see them at UCI road races? When the equipment manufacturers pay Pat off, then it's done. If it's done through the usual channels, 10 years from now it will be a 'discussion.'

There are some road bikes out there with discs already. Heavy and low-priced compared to fashionable racing rigs, it would be interesting to see what their sell-through volume is like.

The pesky issue of loosening Q/R mechs with 'rear mounted' front discs seems to have been forgotten. So, not only does the disc itself need to go through an expensive and risky re-design for road, but the front and rear hub shell, fork blades, fork crown, seat and chain stays need to be redesigned too.

I think it's going to happen. Just not yet.

 

[dsut4392]

Drag in the sense of wind resistance, not rubbing or cross-dressing.

My wrists and back get tired when I ride (and my gut presses up against the top tube), but there are these things called recumbents that are going to make upright bikes obsolete. Watch this space.

You honestly think the difference in wind resistance between a disc brake setup and rim brake setup is likely to be remotely significant? And in the very same post you make a crack about 'bents not taking over the world?

Even if there is significant additional wind resistance from the brake caliper and hub, don't forget you are getting rid of the frontal area of the rim brake caliper arms and brake shoes, plus there is more potential to redesign the rim for aerodynamics when you don't have to provide a flat, near-parallel braking surface.

As for recumbents, they have their uses, but for bike races their advantages (and the drag coefficient of a low-slung recumbent is way lower than the best upright bike & rider could hope to achieve, however much riding a 'bent resembles cross dressing) are outweighed by their disadvantages. You may be trying to say the same is true for disc brakes, but you've yet to give a sensible argument why this is so.