Pros and cons of mechanical vs hydraulic disc brakes?

Simon Brooke said the following on 15/02/2007 16:35:

Not more stopping power - more sensitivity, more precise control. This
really matters for technical mountain biking but probably doesn't matter
very much for cross.

I would suggest that hydraulic discs have more stopping power than cable
discs *for any given input*. Ultimately, both will lock wheels, but my
own experience is that hydraulics do it with far less effort and, as you
say, better control.

--
Paul Boyd
http://www.paul-boyd.co.uk/

"Duncan Smith" a écrit:

Thanks James, that's good info.. Looks like the Tektro lever with the
avid mech. brakes would be a good combo. Do you have a link to the
avid brakes designed to work with the lever?

http://www.sram.com/en/avid/mechanic...es/bb7road.php

There's a little more information in the pdf linked from that page. Of
course if you buy that there's no need to change your levers. Or you could
keep the levers you have and add a supplementary cross lever on the bar top.

The brake hoods is a good question - I don't usually run a rear
brake, though I may change my mind after tuesday's ride in the
wet... I use them for pulling up on when climbing hills a lot though.
It would be tidier if I could remove the levers from the hoods, but
they don't seem designed to be removed easily (Tektro).

Sometimes the lever pivot is just a press fit in the body and can be driven
out with a punch. Sometimes there's a grub screw holding the pivot in place.
Sometimes the bolt that clamps the lever body to the bars holds the pivot in
place.

Maybe you can buy some hoods without levers...?

Indeed you can. They're designed primarily for tandem stokers:

http://www.canecreek.com/ergo_stoker_lvr.html

James Thomson

"Duncan Smith" a écrit:

Feeling somewhat unsatisfied with the V-brake setup on my
cyclocross forks I'm contemplating disc brakes as a solution
and am wondering what the relative merits of hydraulic vs
mechanical are?

Apologies - I came in in the middle and have only just read back to the
start of the thread. Can you clarify your present setup? It sounds as though
you've been using V-brakes with road levers. If so, there are cheaper ways
of improving your braking than buying an entire disk system.

The only drop-bar lever that's designed pull enough cable to work with
V-brakes is the Dia Compe 287V. You should be able to get a big improvement
in brake performance by matching your lever to your brake, or your brake to
your lever.

http://www.sheldonbrown.com/canti-direct.html

http://sheldonbrown.com/canti-trad.html

http://sheldonbrown.com/cantilever-geometry.html

James Thomson

In article .com,
Duncan Smith
says...

Agreed, the normal drop style lever didn't really pull enough wire for
the v-brake, I was thinking of mounting a more conventional mtb style
lever on the bottom of the drop bars (near where the bar end plug
goes).

Why not just use a pull doubler like QBP Travel Agent?

In article . com,
Duncan Smith
says...

The brake hoods is a good question - I don't usually run a rear brake,
though I may change my mind after tuesday's ride in the wet... I use
them for pulling up on when climbing hills a lot though. It would be
tidier if I could remove the levers from the hoods, but they don't
seem designed to be removed easily (Tektro). Maybe you can buy some
hoods without levers...?

They used to be sold as stoker hoods - ISTR Ron Kitching selling the Dia
Compe ones. If you get hold of some old Weinmann levers it's very easy
to remove the blades.

On Thu, 15 Feb 2007 16:35:49 +0000, Simon Brooke wrote:

Apart from the mud issue, disk brakes are less, not more, effective than
rim brakes, because of poorer leverage and less radiant surface.

But potentially more effective because of fewer conflicting material
selection issues.

regards, Ian SMith
--
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On 15 Feb 2007, Duncan Smith wrote:

Feeling somewhat unsatisfied with the V-brake setup on my cyclocross
forks I'm contemplating disc brakes as a solution and am wondering
what the relative merits of hydraulic vs mechanical are?

Only thing I've not seen in the discussion to date is that mechanical
are prone to cables frrzing if they get wet in them and it becomes
cold. Presumably hydraulic don't (until it becomes very cold? What's
the freezing point of the fluid?

regards, Ian SMith
--
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|o o|
|/ \|

Apologies - I came in in the middle and have only just read back to the
start of the thread. Can you clarify your present setup? It sounds as though
you've been using V-brakes with road levers. If so, there are cheaper ways
of improving your braking than buying an entire disk system.

The only drop-bar lever that's designed pull enough cable to work with
V-brakes is the Dia Compe 287V. You should be able to get a big improvement
in brake performance by matching your lever to your brake, or your brake to
your lever.


So, the bike came with some sleek carbon forks which only allowed up
to 28mm width tyres. Cycling to work on un-gritted icy back roads
made me a little twitchy, so I let the LBS fit some cross forks and
either canties or a v-brake - they went for Vee in the end - Shimano
Deore. I did mention about the 287V, but they thought that the front
cable was short enough that it wasn't necessary - and kind of isn't,
at least for one of my wheels. The other wheel has a slight, slight
buckle that means I just have to slacken of the v-brake a little, but
the result is that by the time I pull the lever (standard road lever)
so that the pads bite the rims, there isn't all that much free travel
left before touching the bars, which in the wet is definitely sub-par.

The idea was that it would be quick and easy to swap the wheels over
depending upon the weather, one with a 28mm tread, the other a 35mm
studded tyre, but that didn't really work out because the rims are
different widths - and it takes longer to dick with the vees than it
does to change the tyre over.

Strictly speaking I could probably make do without, but I wouldn't
mind trying out some discs anyway. Never had discs before.

Regards,

Duncan.

Simon Brooke wrote on 15/02/2007 16:35 +0100:

Apart from the mud issue, disk brakes are less, not more, effective than
rim brakes, because of poorer leverage and less radiant surface.


I have cable and hydraulic rim brakes and hydraulic disk brakes and I
can't believe that anyone who has ridden all three extensively could say
what you have just said.

--
Tony

"...has many omissions and contains much that is apocryphal, or at least
wildly inaccurate..."
Douglas Adams; The Hitchhiker's Guide to the Galaxy

Duncan Smith wrote:
The idea was that it would be quick and easy to swap the wheels over
depending upon the weather, one with a 28mm tread, the other a 35mm
studded tyre, but that didn't really work out because the rims are
different widths - and it takes longer to dick with the vees than it
does to change the tyre over.

Strictly speaking I could probably make do without, but I wouldn't
mind trying out some discs anyway. Never had discs before.

My guess is that it would be cheaper and easier to replace one of the wheels
so that you have a pair with similar rim width, and then either get a 287V
lever or switch to cantis. I wouldn't want to deny anyone the pleasure of
spending money on bike-bling though.

Anthony