Front v brake, rear disc?

[lewis noble]

Hello

I have not seen much comment on how this system works in practice, the option that is now available and 'recommended' on the Club Tour.  Can anyone comment??

Whenever I discuss it with cycling friends, they express surprise at this set-up - why have a (potentially?) more powerful disc brake on the wheel more likely to skid, why not the other way round?

But thinking about it, it makes sense, I guess.  You can retain a light and comfortable fork, run lightweight rims, and have at least one brake that works pretty much 100% whatever the conditions.

How does it work in practice??

Lewis

[Far-Oeuf]

it's not really about power, because a v-brake can overwhelm either front or rear (ie, you can lock the wheel).  personally (just ordered a CT with v-brake front and disc rear) I am fed-up with rebuilding wheels with new rims.   This is required because I mainly cycle in mountains with a loaded bike in poor weather (spring/autumn, as well as summer).  

The disc on the rear means I shouldn't need to replace a rear rim, though I won't really get much more usable power.  In theory the disc also stops the rim overheating during descents, but I've never experienced that with v-brakes and I think that's largely a poor-technique red-herring.

I went for the light fork on the CT, which (trusting the designers) isn't built for a front disc.   No big deal, at least I'm only going through half as many rims now.  I also don't really want a dished front wheel.

I've had a front/rear v-brake setup on a 130kg bike+rider in various mountain ranges, and never had any sort of brake problem; always had enough stopping power.   Personally, it's about rim-wear for me.

EDIT: oh, and you modulate the brakes based on feel for grip.   So whatever the power of the brake (whether worn pads, disc or v) you'll just get used to how it feels.   you do this already, as your front and rear brakes are rarely in perfect power-balance.

cheers,

[jags]

i would say that set up has anything to do with skidding more stopping power than anything.
all a matter of feel  and how you apply the brakes.

[Andre Jute]

The disc on the rear means I shouldn't need to replace a rear rim, though I won't really get much more usable power.  

I think you're likely to find it six of one and half a dozen of the other. Either you rebuild the rim occasionally because the V-brake has worn it through, or you replace the pads in disc brakes much more often than you ever replaced brake blocks or rebuilt wheels. I had a front disc brake on Gazelle Toulouse, and I hated it for the amount of maintenance it required, and I hated it again for it's crude on-off stopping without decent gradation. (From memory, the disc brake model was Shimano 485.)

The best hub brakes are Shimano's roller brakes. I had the best of them, the model 75, on my Trek Smover and they stopped harder than any V or disc brakes I ever met, though they too could be a bit sudden. The point is though that maintenance is a squirt of special grease through a hole every x miles, so that you could service it with your Rohloff, and then have a proper low=maintenance bike on which you need never rebuild the wheels unless you trash them on very rough roads or someone else does it for you with a motor vehicle. I've also had the older, cheaper roller brakes than the IM-75 and they were still pretty good, but for mountain passes you definitely want the best Shimano offers. (The roller brakes use disc brake tabs to react torque, so the tabs must be on the bike...

It's a pity Shimano's roller brakes aren't more popular outside Germany and The Netherlands.

Roller brakes on one of my bikes are pictured at http://coolmainpress.com/BICYCLINGsmover.html -- not that the thing that looks like a disc brake is a cooling disc for the roller brake, all of whose action happens inside a sealed chamber.

[Far-Oeuf]

true, but I'm more inclined to need to replace a rim while away which I've found to be quite problematic.   sometimes all you can do is buy a full wheel, which means losing your existing hub/spokes.   and the replacement isn't always great quality, leading to regular spoke problems.   replacing a rotor or pads is much easier and simpler, when 'on the road'.   perhaps quite a niche advantage, I agree.

EDIT: btw, my preference is for v-brakes all round.  For me discs are resolving a particular problem I experience, but nothing to do with 'even more' stopping power.

cheers,

[Swislon]

Hi Lewis,

I have the new Club Tour with this setup with Grand Bois 32mm tyres.
In practice I haven't really felt much difference as of yet. I can "feel" there is more oomph available at the rear if needed but have yet to call on it.
It does add weight to the back, not as much as the Rohloff but more than a rear V brake or canti.

As far as locking up the wheel all I can say is that from bitter experience, I know I can lock up a V brake just as easily. I have an enormous disk brake on the rear of our tandem and we have yet to lock that up and that gets a lot of abuse on the hills around here but a tandem is a bit of a different animal.

Modulation feels good (Avid BB7 and drop bars) but yet to be tested in really wet weather.
The good thing about the Club Tour is it will take disc, mini Vs or Cantis. I had it fitted with disc because I wanted to try but knew that I could swap it out if I didn't like it. I went for a normal rim not the disc specific to allow that option.

Steve

[lewis noble]

Interesting comments everyone, and thanks Steve for your 'actual' experiences / comments on this setup.

My relatively low mileages do not justify changing, and the XT v brakes on my Ripio work so much better than pretty well any rim brakes I have ever had, so I am content with what I have.  But if I do wear out the back rim, I would consider that arrangement.

Lewis

[David Simpson]

On my Nomad, I have a V-brake on the front and a disc brake (Magura MT2) on the rear. I wanted disc brakes because I commute regularly in the rain, and disc brakes are great in the rain. I can't put a disc brake on the front because there are no mounts on the Nomad fork.

Both disc brakes and V-brakes are great brakes, and capable of skidding the tires. I haven't noticed any difference in the braking power between the disc and V-brakes on my bike, except in the rain.

I wouldn't worry about whether the rear brakes are more powerful than the front. Both brakes are powerful enough. Go with what works best for you.

- Dave