S.D.XC

Just a random question...has anyone done this?

If they have...

Is it good?

Or bad?

ed 

Search fctn

S.D.XC

huh?

sickmtbnutcase

Did it in temporarily when my Magura Louises bit the dust. Slapped a Avid mechanical disc on the front, V on the rear. Worked great. Eventually went dual disc (new rear triangle was required, broke that a week later). For most use, nothing wrong with disc on front, V on rear. Survived a trip to Moab with that setup, so it works.

chelboed wants you to use the search function. I didn't before posting and you probably should as there's likely plenty more out there on this subject.

S.D.XC

oh, i'm sorry... (not sacarstic)

=(

S.D.XC

hmmm

cant find it....

sickmtbnutcase

https://www.bikeforums.net/mountain-biking/24293-front-disc-rear-v-brake-setup.html
https://www.bikeforums.net/mountain-biking/152825-brakes-disc-front-v-rear.html
https://www.bikeforums.net/mountain-biking/33150-front-disc-rear-v-brake.html

cobba

In the late 1990's and early 2000's there were plenty of them produced.
Here's an example of one: https://archive.giant-bicycles.com/cn/030.000.000/030.000.000.asp?year=2001&model=9511

santiago

Mullet. Business in front, party in the back.

Berg417448

I have one bike set up like that. No problems.

BearSquirrel

Since the rear is effectively just a drag brake, this is actually ideal.

S.D.XC

wow thanks everyone...i might just do that...but does anyone sell just one disc brake??

S.D.XC

and also, other than the cable length, are the front and rear disc brakes exactly the same?

mtnbiker66

Please explain.....

BBnet3000

since the rear is often used as a speed limiter rather than for sheer stopping power, having the more powerful brake on the front is the better choice, and you can save a slight amount of weight by having a v on the back.

for road bikes and tandems it might be better the other way around though, because with higher pressure tires the rear rim brake can built up heat and thus pressure in the tire, and for tandems because with the heavier weight you will go through rear pads like hell if you are using it on hills all the time.

Servo888

The amount of heat built up at the rim is negligible as aluminum dissipates heat very well.

kenhill3

No. It is not 'ideal'.

I'll take discs front AND rear every time. True that the front has the most stopping power. But in technical situations, especially downhill and with loose trail surfaces, the rear is the one that gets more constant/sustained use- the front often has to be feathered or not even used at times or you will lose control. Being better at stopping power than a v-brake, a disc in the rear will always be a more effective partner to a disc in the front. Just my own opinion.

But, to answer the OP, disc front and V rear will probably work just fine. I have not personally done it, but I'm gonna guess that a mechanical disc (vs. hydro) in front would be the best choice in terms of more closely matching the modulation characteristics of V's and discs.

S.D.XC

hmmm...

but i ride XC, so i suppose it'll be ok...

BearSquirrel

Good point, tandems, tourers and utility bikes behave different as the rear axle is directly loaded. So that rear brake will actually be useful on downhills. So ... discs on both are ideal.

For the typical non-cargo single occupant scenario, front disc only is all that's ideal. I would recommend anyone who upgrades to go with this scenario as it is the cheapest, lightest and does not compromise any rear wheel weight with a reduced dish.

santiago

This is just an observation: I've browsed through various tandem vendor web pages and you would be hard pressed to find discs on tandems. I would have expected discs to be in use more frequently. That's not to say that they are impossible to find, but it seems that they are not used often. I'm not talking about X-mart bikes either, I'm referring to tandems that cost thousands of dollars.

Anyone have any insight into this?

kenhill3

That IS interesting. I have a friend who is a custom frame builder, and has built a number of tandems. I have not seen him build tandems in the last ten years or so, but in the past, in addition to supplying 40 spoke rear wheels, he was always trying to provide extra braking for the rear wheel. I think I recall a setup where he used a drum brake in addition to cantilevers. The stoker had a lever for the drum.

BearSquirrel

I read a warning on the Surly website of relying on "just" the front for their Big Dummy cargo big. The thing with these bikes is that the big limit to speed is aerodynamics. But on a downhill, extra weight will change the balance of frictional force vs. gravitational force in the favor of gravity, you go faster. Similarly, with tandems, you've got two people cranking with effectively the same aerodynamic profile.

So I can see where using the rear becomes VERY important under these circumstances whereas for a mountain bike going downhill, the rear becomes so unloaded that it's almost useless unless you like fishtailing.