Top 5 - Objections to Road Bike Disc Brakes (And Why We Disagree)

Cycling is a sport steeped in tradition and history, so change is often viewed with suspicion and downright hostility. Are disc brakes an industry marketing scam, or just part of the ever-changing evolution and improvement of the good old bicycle?

[blindfoldblaster]

Well, personally I think that rim brakes are easier to adjust and have a simpler maintenance process

[reginaldscot]

Reason 6, I dont want to have to mess with hydraulic oil on my bike. I just don't want the hassle.
7. I don't need them
8. Cost

[lifeshard]

just feel like adding my 2 cents:

1) I have 4 bikes (Aero road, climbing, winter, TT) I love that I can switch wheels with relative ease between them if needed. I'm not going to replace all 4 bikes and 3 sets of training wheels, and 3 sets of race wheels unless I absolutely have to.
2) When panic braking, when it actually matters that I stop because a car pulls out in front of me, I lock up my wheels 99% of the time. Disc brakes are amazing for planned stops...but if I'm planning a stop I can just adjust before hand on rim brakes.
3) I suck at being a mechanic but I can change out brake cables and housing with ease.
4) They are ugly, they are getting better but 90% of the time I'll choose the rim brake model.
5) This sport is already really expensive, I am a little resentful of most big bike manufacturers (I love my Tarmac and Venge because they are good bikes, I don't ride them because Sagan rides them, or because they sponsor the most world tour teams) and I feel like they are ramming discs down our throats. Of course the pros will start to ride discs because the sponsors will "insist" they ride them.

[ricardofigueiras]

OMG! another disc brake video!? Now i start to believe in a marketing scam! Disc brakes are fantastic, but there are people that don´t like it, so let the two options be!!!

[nerdexproject]

Actually they look hella sexy. But as a mountainbiker I might be biased on that. haha

[sunfire]

the only thing keeping me from going to discs is the sweet sweet sound when you're braking with carbon wheels

[waynosfotos]

The whole disc vs rim brake argument, everyone misses the really reasons why manufactures have not brought these in earlier.
One major reason discs are being pushed now is the uptake of carbon clinchers. Manufactures know the dangers of failure with heavy braking, so lets change to disc.
Now discs do have design disadvantages which everyone appears to just ignore, why, because it is not obvious but creates some significant changes in forces to the bike.
One, a disc bike needs to have cross spoking with a higher spoke count, why, because it places significant rotational forces through the spokes, rim brakes do not, as the force is applied directly to the rim. A disc wheel is also dished to accomodate the disc, dished wheels are weaker and need a higher spoke count. A disc applies forces to only one side of the fork, causing rotational twisting, why through axles are need to transfer the force to the opposite fork. All this means a stronger fork and a stronger wheel with more spokes, basically a heavier slower wheel which creates more drag.
Now to the back wheel, the axle length is wider by 5mm, therefore the chain line is different, this creates problems with the chain line on short chain stays, yes the brand new groupsets have made allowance for this. But it is not idea for chain alignment.
So in summary, yes we get better wet weather braking and the hot brake surface is removed but a lot of design and comprises are now being built into the bike. I am not a fan of these forces being moved to the end of the fork and rotational loading put through the wheels, especially in the road industry striving for the lightest products. We know wheels already fail and give spoking problems, now we put more forces through them.
No thanks I will sit on the fence a little longer, plus all my old wheels we be obsolete going disc.

[nickrogers]

Hydraulic disc brakes are awesome. Once you've tried them everything else just won't do.

[jubei]

We're all forgetting how simple a bike should be and the beauty of simplicity. Disc breaks with hydrolic fluid, becomes dangerous if people start servicing it themselves and did not correctly serve to manufacture spec. I have both types of brakes and find a well tuned rim brake just as effective, I emphasize well tuned. Oh and if people start "upgrading" their perfectly good bikes and believe marketing hype, all good for me.

[Raumance]

2:50 Really? A tight wearing roadbiker worried about looks?

[iberiksoderblom]

The only real advantage of discs are on real brake performance, and that they dont eat your rim.
But I've never had rims that long (old) that I've changed them for reason of wear.
They are changed for other reasons before that.
Also I dont have any steep descents from mountains.
So in order to have a lighter, more aero bike, having no issues with quick-shift and saving money on the brakesystem as well, I stick to rimbrakes.

[njx]

One of the main pro's of disc brakes for me is that you don't brake on the rim.
If I pay 2k or more for a carbon wheelset it's nice to know that I don't have to limit the use to races or have to worry about wearing it out when I ride in the rain.

[deimosphob]

The whole reason people point out locking up the wheel when talking about good brakes is that at higher speeds it is harder to stop a wheel to a dead stop and maintain it as friction is being applied, logically if it is able to do that, it is able to do less demanding, gentle drops of speed that are more efficient.

[ZOB]

I would be willing to say that a chain ring or cassette is just as dangerous to the rider as a disc brake.

[NeoDerGrose]

You forgot one important thing. Disc breaks are much more likely to overheat. The braking surface is smaller and therefor uses higher pressure and the disk is smaller than a rim and therefor couldn't transfer heat as quickly. This could be an issue when running down the alps and not being fast enough.

[rodgerselbyjr]

My disk brakes not only look great they saved lives ;) (For a guy who lives in the middle of Philly where children and grown adults run, bike, and walk straight into an oncoming cyclist)

Rim Brake Incident: A team of runners were running along the recreational train (shared by both bikers and pedestrians) and one of the runners went straight from the pack on to the direct path I was going (at 24 mph in the rain, I was about 25 ft from her) and she didn't notice the 230 lb guy on a bright green bike coming towards her until I shouted. Long story short the rain made breaking harder of course and I manage to avoid her with 3 ft to spare.

Disk Break Incident: A trip of school children going through one of the wooded trails, of course the kids run around and I pass slowly of course. Anyway there was a large break in the group (the second group couldn't be seen in the distance from the first group). Anyway going on a downhill section and again the group shows up, kids still running around, the adults in this group could careless about the bike traffic and my large self manage to stop in a very short distance despite going down hill with my weight the bike stopping confidently as a kid runs out within 15 ft of my bike.

Even as a racer, Ill pick disk brakes first every time :)

(Needed my moment to rant, thank you!)

[xxiipp]

I don't think the 'you're not a pro, extra weight doesn't matter' argument is valid. Everyone, no matter who they are, wants to feel like their machine is enabling them, as best it can, and not holding them back.

[tywin]

There's also the (imo) overlooked fact that disc brakes don't wear out your rims, and also the rims themselves can be made lighter because they're not being built thicker to handle rim braking forces. So you don't wear out your heinously expensive carbon rims, and the rotational weight is lower. Win-win.

[billlieu]

About 2 months ago after riding 20 miles, I stopped at my normal rest/turnaround point. When I picked up my bike to prop against a fence, the rear wheel with disc popped out of the dropouts and pulled the derailleur cable out. Since I was certain that the rear quick release skewer was properly tighten before my ride, I searched the internet to see if this was a common problem with bikes with disc brakes. I found info that states that the physical force of a stopping disc on one side of the wheel causes a twisting motion that loosens quick release skewers, and twists the axle out of dropouts. It was suggested that the skewers should be inserted backwards to normal on the rear wheel (handle on cassette side) to minimize the problem. Also, the uneven force applied to one side of a front axle by a disc on one side of the wheel is not compatible with quick release skewers or forward facing dropouts on some front fork design.

[MrJonas]

From a maintenance standpoint discs are definitely more expensive to maintain. Bleeding a hydraulic brake takes longer than adjusting a rim brake and the disc pads are quite a bit more costly too. I guess you could argue you don't have to replace the rim after the braking surface is worn down but realistically after 15, 000 km or w/e the disc wheel will probably need to be rebuilt as well