Why not disk brakes?
 

Ok. All childhood I rode in a single speed bike where brakes were inside rear hub (not sure what is the name). Basically, turn pedals backwards and rear wheel locked.

Now I see V-brakes everywhere. And I'm not impressed with them. I have 4 bikes given to us, I did all kind of adjustments, lubed/checked cables, etc. Wheels trued, you name it. And I still have hard time locking wheels with those brakes. They require considerable effort to engage. OK with me, but my girls (11 and 6) definitely have problems operating them.

I got new bike for myself and it has disk brakes (cable). It's like day and night. I'm not racer, I don't care about weight. I definitely like disk brakes better. There is no comparison. They are easy to adjust, easy to operate. So why not disk brakes on all bikes??

I'm looking for casual/hybrid bike for my wife and I'm 100% set on going disk brakes. But I don't care about 20+ speeds. I want to get 8 speed IGH and disk brakes. I don't see any women-specific bikes like this (IGH + disk). Why not? And is it possible to install disk brakes on IGH hub?

If you want disc brakes, the hub has to have a mount for the disc and the frame & fork have to have mounting points for the calipers.

But rim brakes -- whether they're caliper, cantilever, or V brakes -- are very effective at stopping bikes. They're still standard equipment on many high-end bikes. If you've got decent rims and pads and they're dialed in, stopping distance and effort should be comparable to disc brakes. Without knowing the specifics of your kids' bikes, I'd strongly suspect your braking problems have more to do with the quality and condition of the parts than the type of braking mechanism.

The "pedal backward" brakes you remember are coaster brakes, by the way.

Why not? because you Already got a frame without the mounting spots?

+1, want a bike with Discs for the wife .. Buy one, so equipped.. If the weather is Nasty discs are good ,

if she would Never go out in that sort of weather it's as not important.

SkyDog75 is correct, rim brakes, properly made and with good pads can stop a bike every bit as well as discs. Your problems are likely due to poor quality brakes and pads on the kid's bikes, not an inherent design defect. There was a VERY long and somewhat acrimonious thread a few weeks ago debating the merits and demerits of disc brakes on bicycles. A search should locate it and reading it should keep you entertained for a fair while.

As to "locking the rear wheel", coaster brakes were good at that but little else. It's a very poor way to control bike speed.

Never try hydraulic discs. Your bank account may regret it if you do.

Rim brakes will stop a bike just as well as disk brakes, in dry weather anyway. Your rim brakes were not operating correctly or of lousy quality.

You want your kids bending rotors?

I can't say this enough. It's never been about stopping the wheel, it's about stopping the bike. The limiting factors have never been the brakes themselves, but tire traction, and geometry which determines the maximum front braking force that won't cause an endo.

Greater brake stopping power has always been possible simply by changing the leverage built into the brakes or levers, so what we ride isn't set by practical or engineering limits, but by what seems right for average riders.

That said, I understand that women tend to have lower hand strength then men, and likewise children, but I wonder about the ratio of hand strength to weight. If your girls (includes the wife) are having problems with the hand brakes, possible better setup, or a substitution of a higher leverage handle is all that's needed.

Yes, you all correct that kids bikes all cheap stuff. And seems like they all have different kind of setups. V-brakes but different ways to adjust pads, etc. I'm not about to go and try to find new good pads for them.. I'm just curious about whole thing in general. For the wife I still think I would want disks..

The Avid SD 7 v-brakes I run are coupled to these:

Love Lever 2.5 from Paul Component Engineering

And they are capable of throwing me over the bars if I'm being a ham-handed twit that day.

In general rim brakes are not as good stoppers as discs. Even the best rim brakes cannot compare against the best discs. I would love to see a rim brake which was as powerful as my magura gustaf's. This is of course in the mountain world where tires are wider and stopping traction is no problem.

In the road/hybrid world discs don't necessary give better stopping power since tire traction is limited (personally I have yet to see this happen but whatever...) but thwn again you get the same amount of braking with a lighter touch.

I personally like the fact that I can get the maximun brake power with no effort at all with one finger against all the rim brakes I've tried which never seem to get to the max power no matter which pad, which brake and what power/amount of fingers

Also it's not a nice feeling when your lever action starts 1cm from the open position and even when the lever is touching the bar there isn't good brake power. In a steep downhill. When you really need to stop. Against the fact that with a good set of discs you would have otb'd an elefant with the brake force you just did.

And let me tell you! Rim brakes are the worst in the winter and rainy conditions. Inthe right kind of cold you get maybe 5% of your normal braking power. If that. And in the rain all the sand/clay/grime sticks to your rim and grinds away at it with the wet pad. It's like an ultra coarse honing stone against your aluminum rim.

Please go find the previous thread on this debate and reopen it. We don't need another multi-page contest of rim vs disc brakes.

It's the new "chain lube" debate.

I suspect that for higher end competitive riders where weight and speed are a concern, rim breaks are superior in terms of being lighter and having extremely simple maintenance.

I think part of it is also that people imitate what the pro road cyclists do. That's one reason why a lot of people eschew kickstands and front fork suspensions.

If you have rim brakes and an expensive wheelset, don't ride in the winter on hills. Hard braking with slush and dirt on your rims can ruin them very quickly.

I would not buy or build another bike without disc brakes. Period.

OK, you're looking at a combination of three smaller-market niches:
1: women-specific design
2: internal-hub gearing
3: disk brakes

I'm not surprised you couldn't find such a bike. If you want a bike with all those characteristics, you'll have to do some customization. IMO, you would be better off finding a women's bike with disc brakes and convert it to an internal gear hub. (Yes, internal gear hubs can be had with disk brakes.) A quick search turned up this: Hybrid Bikes Cafe Latte Disc 2014. Converting it to an internal hub would add another couple hundred dollars to the bill.

the OP has convinced me that he or she is of the opinion that locking up the rear wheel is what's important in braking. if that's important just get a bike with a coaster brake hub and have at it. i was able to lock up my cheap sturmey archer coaster brake hub with little effort when i had it on one of my bikes a while ago.

Go to a bike shop and test ride some bikes with rim brakes and with disc brakes.

For little kids, low hand strength is a problem for braking, which is one reason why a rear coaster brake makes sense for a little kid's bike. Some women have very weak hands too.

Shimano Alfine is an IGH that's available with disc brake.

Very true. My road bike has rim brakes, the MTB has hydraulic disc brakes.

When I'm riding the MTB the disc brakes will stop the wheel with minimal effort from me. That doesn't mean I stop any faster. Comparing the two bikes on the road (i.e. taking out factors like the lack of tyre traction on loose gravel etc), the road bike takes longer to stop the wheels but the bike stops at the same time. The MTB's brakes are powerful enough to lock the wheels which just means I slide to a halt. I don't ride the MTB much these days, so really have to be careful if I am riding on the road to get somewhere, because if I do misread a situation and have to brake hard the chances are I'm going to slide and if I slide the chances of sliding into something are increased.

The main advantages I see of disc brakes are that you don't wear out the rim, and it doesn't make any difference to braking if the rims get wet or muddy. Where children's bikes are concerned one major disadvantage is that if you bend the discs themselves the brakes will rub and from what I gather straightening the disc is the sort of thing that either costs money or takes a huge amount of time.

I have never been on a bike that v brakes wouldn't put you over the bars even on a cheap bike. Perhaps you have side pull cantilever brakes which are not as effective especially on cheap bikes. Something is wrong with your brakes take the bike to a LBS and get them fixed correctly then decide on your new bike.

There is nothing wrong with disc brakes they are just more expensive and so usually are only available on upgraded models of bikes.

This one is even worse in the touring crowd!

Disc brakes yes!!!! Disc brakes are far more logical and mechanically perfect. The do NOT ruin rims that can be really expensive. An ave cyclist that posts here can change out a disc and pads when they go bad themselves, saving a lot of money. If the rims are ruined most people have to have a LBS sell them a new rim, and rebuild the wheel. That is expensive. Also a rim designed for disc brakes can be any shape that makes it stronger and more aero.

Lastly cyclist on a long ride or cross country cyclist that have a rim break or go bad are on foot. If a disc brake goes bad, the bike still has one good brake. Disc brakes will do for bikes what they did for cars.

Based on experience, I don't agree. Hydraulic bicycle disc brakes are not particularly expensive, work well, require little maintenance and are durable. Get what you want.

BTW, to the OP, locking the wheels indicates brake failure, not success. Brakes work by converting kinetic energy (motion) into heat thus slowing you down. The wheel has to be turning for that to happen. That's why cars have anti-lock brakes -- to keep the wheels turning and thereby keep the brakes working. Better brakes generate more heat (i.e. have more braking power), require less user force (one finger braking), provide better control (aka modulation) and work equally well under all conditions (e.g. when wet). Disc brakes deliver all these benefits.

Good brakes make a difference which is also why, for example, Porsche owners spend tens of thousands to upgrade their brakes from the orange ones to the yellow ones. That, I agree, is expensive.