Front disc and rear canti?

[Old jon]

Conventional brake bolted to centre of fork crown, braking forces similarly centrally disposed.
Disc caliper bolted on fork leg, not a chance. I would guess a bit of veering to that side, until the rider got used to compensating for it.

 

[mcshroom]

Surely other than there being a little twisting motion anti-clockwise on braking, by the time you are getting to the steerer and headset interface it's going to make very little difference how the brake on the fork is operating?

 

[Old jon]

Some years back, 1985 or so, I borrowed a Honda equipped with a single disc, and that did twitch quite severely. I did not ride it long enough to get used to it.
Should mention that my solo motorbike had a twin sided drum brake.

 

[PpPete]

Er... those are dual pivot, not canti

And canti brakes are NOT necessarily rubbish.
I think I know where that pic comes from and I've tackled that same descent with cantis. The limiting factor was rubber/road interface not the brakes.

 

[Ajax Bay]

Picture of broken framed GIOS

Not cantilever brakes, not a XC bike and not steel.

 

[dan_bo]

Not cantilever brakes, not a XC bike and not steel.

No sense of humour or poetic license either.

 

[Jody]

As for disc brakes, I honestly believe that the supposed benefits have been over egged and exaggerated, not by riders, but by the industry. An industry that benefits from the added costs involved in getting the rider to believe that they are missing out or placing themselves in danger or not getting the best from their bikes, unless they are using disc brakes.

Disc brakes (decent hydraulic) are a massive step forward from V's. No rim wear, don't have to worry about slightly out of true wheels rubbing, change pads in seconds and easily but the main selling point for me is massive power using 1 finger on the lever. I have always been a fan of V's but you can't compare the power and control to discs. You just know they are going to work in the same way every time, unlike rim brakes when wet or muddy.

 

[Dirk]

I can't quite grasp what meaning that picture is trying to convey in the context of this thread.

 

[Ajax Bay]

I can't quite grasp what meaning that picture is trying to convey in the context of this thread.

@dan_bo 's already excused this by claiming a sense of humour (bet the bloke who came a cropper on Hardnose on the Fred Whitton had trouble retaining his sense of humour) and 'poetic license (sic)": "the freedom to depart from the facts of a matter or from the conventional rules of language when speaking or writing in order to create an effect" - though what intended effect was not clear - well, not to me (or you).

 

[Kajjal]

In which case it is the fork or wheel that could be the problem - not the frame.
However, I would presume that any conversion would use the appropriate components and would therefore not be problematical.

Its all the whole bike, the force of a disc brake is several times that of a rim brake. Road bikes with disc brakes are designed to with stand the forces involved.

 

[velovoice]

I have my eye on a frame which takes a long drop rear cantilever brake. My experience of these is not good, regardless of type of brake / pad / levers / rim, especially in the wet.

I know that in theory most braking is done by the front brake, but I find it difficult to judge in the real world how much I use the front compared to the rear.

Assuming I use an appropriate fork / wheel / lever / brake combination what's likely to happen if I run a front disc with a rear cantilever? Anyone running a set up like this?

I'm running exactly that on my Surly Cross Check after simple swap out of the fork for a Surly Straggler front fork. Works brilliantly.

 

[Dirk]

Its all the whole bike, the force of a disc brake is several times that of a rim brake. Road bikes with disc brakes are designed to with stand the forces involved.

Sorry, but both those statements are simply not true.
Some disc brakes may well have better modulation than some rim brakes; but as for being 'several times' more powerful? I doubt it. And in any case the limiting factor for how much force is transmitted through the frame is tyre grip - which can easily be exceeded with any decent rim brake set up.
Road bikes with discs are constructed essentially the same as any other road bike, but with minor adjustments to allow for disc instead of rim brakes; it does not require a total frame redesign - just slight modification of an existing design would suffice.

 

[Kajjal]

Sorry, but both those statements are simply not true.
Some disc brakes may well have better modulation than some rim brakes; but as for being 'several times' more powerful? I doubt it.
Road bikes with discs are constructed essentially the same as any other road bike, but with minor adjustments to allow for disc instead of rim brakes; it does not require a total frame redesign - just slight modification of an existing design would suffice.

The increased force is in part where the better feel / modulation comes from. Not having cables and using hydraulic fluid also helps.

Unless already capable most disc brake frames were strengthened at key points. A simple example is the QR on a rim braked bike does not have to be done up as tight as one on disc brake bike to stop the wheel moving in the forks under braking.

You said a complete redesign, i just said designed to withstand the forces involved.

 

[Dirk]

The increased force is in part where the better feel / modulation comes from. Not having cables and using hydraulic fluid also helps.

Unless already capable most disc brake frames were strengthened at key points. A simple example is the QR on a rim braked bike does not have to be done up as tight as one on disc brake bike to stop the wheel moving in the forks under braking.

You said a complete redesign, i just said designed to withstand the forces involved.

You said 'it's all the whole bike'.
I said 'it does not require a total frame redesign'.

 

[Ajax Bay]

Unless already capable most disc brake frames were strengthened at key points.

Which 'key points' on the frame would those be, please? Remember, this is in the context of after market fitting of a front disk brake by changing the fork et al.