Disk brakes?

Quoted message said:

I am looking at getting a MTB at around the Deore LX level. Many bikes at
this level use disk brakes. A number of years ago the general consensus
seemed to be that these where heavier, more complicated, put extra strain on
wheels, and did not work as well as cantilevers except in very muddy
conditions. Has this changed to any degree since?

Sticky

Not really.

However (I love that word!), the extra weight is small, the extra
complication relates mainly to the vulnerability of the disk to bending
or warping. Modulation is generally better with rim brakes unless you
go with hydraulic actuation, but that adds a little extra vulnerability
because its more difficult to attempt a repair in a remote location. A
small consideration, really. Removing the wheel can provide the
opportunity for screwing up the pads if the brake lever is pulled,
resulting in overextension of the pads.

The extra strain on wheels is by and large a red herring. If the extra
torque is a problem, then the wheel is marginal for riding anyway. A
hub brake does preclude the radial spoking that some owners find cool.

A disk brake does eliminate a major source of wear on the rim, and
doesn't heat the rim, tire and tube. Excessive heat can be a problem in
some situations.

--
Ted Bennett

Ted Bennett said:

Quoted message said:

I am looking at getting a MTB at around the Deore LX level. Many bikes at
this level use disk brakes. A number of years ago the general consensus
seemed to be that these where heavier, more complicated, put extra strain on
wheels, and did not work as well as cantilevers except in very muddy
conditions. Has this changed to any degree since?

Sticky

Not really.

However (I love that word!), the extra weight is small, the extra
complication relates mainly to the vulnerability of the disk to bending
or warping. Modulation is generally better with rim brakes unless you
go with hydraulic actuation, but that adds a little extra vulnerability
because its more difficult to attempt a repair in a remote location. A
small consideration, really. Removing the wheel can provide the
opportunity for screwing up the pads if the brake lever is pulled,
resulting in overextension of the pads.

The extra strain on wheels is by and large a red herring. If the extra
torque is a problem, then the wheel is marginal for riding anyway. A
hub brake does preclude the radial spoking that some owners find cool.

A disk brake does eliminate a major source of wear on the rim, and
doesn't heat the rim, tire and tube. Excessive heat can be a problem in
some situations.

I was a retro grouch too but having gone to disc brakes I'm a total
convert. No noise, no worn rims, no problems and they WORK! Best thing I
ever did. I use Shimano XT.

Friday

Sticky Wicket said:

I am looking at getting a MTB at around the Deore LX level. Many bikes at
this level use disk brakes. A number of years ago the general consensus
seemed to be that these where heavier, more complicated, put extra strain on
wheels, and did not work as well as cantilevers except in very muddy
conditions. Has this changed to any degree since?

Sticky

Nope..LX level Vbrakes are better than their discs. If ya gotta have
discs, get hydraulic..which has it's own set of 'issues'.

"Sticky Wicket" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

I am looking at getting a MTB at around the Deore LX level. Many bikes at
this level use disk brakes. A number of years ago the general consensus
seemed to be that these where heavier, more complicated, put extra strain
on
wheels, and did not work as well as cantilevers except in very muddy
conditions. Has this changed to any degree since?

Sticky

There was a long discussion about how a boutique alloy skewer is not strong
enough to counter the massive downward force a disc brake causes on the
front wheel, potentially causing the front wheel to fall off the fork ends.
Whether or not it's true, it did contribute to my already retro-grouchy
dislike for disk brakes.

It's a shame that suspension fork nowadays (and mtb frames) don't even come
with brake studs. There is a reason I haven't bought a mountain frame or
fork newer than '04. V's have a plenty of stopping power for me.

Ted Bennett said:

Quoted message said:

I am looking at getting a MTB at around the Deore LX level. Many bikes at
this level use disk brakes. A number of years ago the general consensus
seemed to be that these where heavier, more complicated, put extra strain on
wheels, and did not work as well as cantilevers except in very muddy
conditions. Has this changed to any degree since?

Sticky

Not really.

However (I love that word!), the extra weight is small, the extra
complication relates mainly to the vulnerability of the disk to bending
or warping. Modulation is generally better with rim brakes unless you
go with hydraulic actuation, but that adds a little extra vulnerability
because its more difficult to attempt a repair in a remote location. A
small consideration, really. Removing the wheel can provide the
opportunity for screwing up the pads if the brake lever is pulled,
resulting in overextension of the pads.

The extra strain on wheels is by and large a red herring. If the extra
torque is a problem, then the wheel is marginal for riding anyway. A
hub brake does preclude the radial spoking that some owners find cool.

A disk brake does eliminate a major source of wear on the rim, and
doesn't heat the rim, tire and tube. Excessive heat can be a problem in
some situations.

I put Avid BB7 Mechanical Disks on my Rockhopper and haven't regretted it.
I get a little brake squeel once in a while but that doesn't affect
their stopping power which I feel is superior to rim brakes especially
in wet weather.
From what I've been told the BB7's modulate as well as hydraulic disks.
I'll have an opinion on that soon as the bike I have on layaway
is equipped with Avid Juicy 5 hydraulic disks.
and changing brake pads is a lot easier than on rim brakes.
One other small plus is not having to wipe your rims down after
each ride.
If you ride in wet and/or muddy conditions discs are the way to go.
I'll never use rim brakes on my mountain bike(s) again.

Bellsouth Ijit 2.0 said:

There was a long discussion about how a boutique alloy skewer is not strong
enough to counter the massive downward force a disc brake causes on the
front wheel, potentially causing the front wheel to fall off the fork ends.
Whether or not it's true, it did contribute to my already retro-grouchy
dislike for disk brakes.

Not true, at least on most US-market bikes. The reason is the "lawyer
lips" that are designed to keep the front wheel attached even if the QR
is flipped open. 15 years ago I could flip the front QR and the wheel
would fall right out the drops--but now, aside from the "laywer lips", a
couple bikes I've bought have arrived with the fork blades spayed
outwards a few mm--making inadvertent disconnection even more unlikely.
You have to flip open the QR and then you still have to fight the fork
blades to unscrew the QR for a bit. --I'm not certain US needed both
these "features" but we are getting them anyway. :\

I haven't tried a big disk on a MTB [hard-use] fork however; disk brakes
came along just as I was losing interest in hardcore MTB riding. Back
then a disk brake was a $500 custom-shop gadget that would only mount to
a $700 Manitou fork....
~

"Sticky Wicket" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

I am looking at getting a MTB at around the Deore LX level. Many bikes at
this level use disk brakes. A number of years ago the general consensus
seemed to be that these where heavier, more complicated, put extra strain
on
wheels, and did not work as well as cantilevers except in very muddy
conditions. Has this changed to any degree since?

Sticky

Plus points for discs (principally hydraulics):
No rim wear
work in wet/mud
don't eat pads in a single wet ride
better modulation than Vs
less/no adjustment as pads wear
no 'cable' adjustments (open systems)
potentially fewer problems if you buckle a wheel
possibly easier routing for rear brake on full-suspension frames

Plus points for Vs:
cheaper
lighter
no nasty hydraulic fluids
Possibly simpler to fix in the field (I can't actually remember the last
time I had to do major brake surgery in the field though)

Here in the UK (it rains) discs are very popular. Plenty of shops doing a
good trade in converting bikes from V to disc. Hope seem to be doing very
nicely!

Skippy
E&OE

Sticky Wicket said:

I am looking at getting a MTB at around the Deore LX level. Many bikes at
this level use disk brakes. A number of years ago the general consensus
seemed to be that these where heavier, more complicated, put extra strain on
wheels, and did not work as well as cantilevers except in very muddy
conditions. Has this changed to any degree since?

Sticky

stop listening to retrogrouches and try them. if you're not prepared to
put up with better braking, better wear in the wet, better bent wheel
tolerance, better performance in the wet and [with hydraulics] better
modulation, then yes, cantilevers are for you.

DougC said:

Not true, at least on most US-market bikes. The reason is the "lawyer
lips" that are designed to keep the front wheel attached even if the QR
is flipped open.

Is there a Specification for the lawyer lips in the USA? The UK, and I
think ISO, Spec reads:

"9.4.4.2 Wheel retention with open quick-release
With the quick-release mechanism fully open and the brake system
disconnected or released, the wheel shall not detach from the fork
when a force of 100N is applied to the wheel radially outwards and
in line with the drop out slots."

To save you reaching for your calculator, 100N is 22.5lbf, or less than
the weight of most bikes. So the lawyer lips are not intended to hold
against the weight of the bike, let alone the forces created by braking.

Mike

jim beam said:

Sticky Wicket said:

I am looking at getting a MTB at around the Deore LX level. Many bikes at
this level use disk brakes. A number of years ago the general consensus
seemed to be that these where heavier, more complicated, put extra strain on
wheels, and did not work as well as cantilevers except in very muddy
conditions. Has this changed to any degree since?

Quoted message said:

Stickystop listening to retrogrouches and try them. if you're not prepared to

put up with better braking, better wear in the wet, better bent wheel
tolerance, better performance in the wet and [with hydraulics] better
modulation, then yes, cantilevers are for you.

Ditto.

Except I use mechanical disks(BB7s) and still feel that they modulate
better than cantilever. I haven't converted to hydraulics because they
tend to be more problematic, especially in the cold weather conditions
in which I ride. Mechanicals are heavier, by as much as half a pound,
but I did cut down on Twinkie consumption to compensate.

Chris

Chris Nelson said:

I use mechanical disks(BB7s) and still feel that they modulate
better than cantilever. I haven't converted to hydraulics because they
tend to be more problematic, especially in the cold weather conditions
in which I ride. Mechanicals are heavier, by as much as half a pound,
but I did cut down on Twinkie consumption to compensate.

What kind of trouble is there with hydraulic disc brakes
in cold weather?

Quoted message said:

Chris Nelson said:

I use mechanical disks(BB7s) and still feel that they modulate
better than cantilever. I haven't converted to hydraulics because they
tend to be more problematic, especially in the cold weather conditions
in which I ride. Mechanicals are heavier, by as much as half a pound,
but I did cut down on Twinkie consumption to compensate.

What kind of trouble is there with hydraulic disc brakes
in cold weather?

Frozen cables ;-)

Lou
--
Posted by news://news.nb.nu (http://www.nb.nu)

Quoted message said:

Chris Nelson said:

I use mechanical disks(BB7s) and still feel that they modulate
better than cantilever. I haven't converted to hydraulics because they
tend to be more problematic, especially in the cold weather conditions
in which I ride. Mechanicals are heavier, by as much as half a pound,
but I did cut down on Twinkie consumption to compensate.What kind of trouble is there with hydraulic disc brakes

in cold weather?

On the colder days(below 25 F), my hydraulic cronies complain of
reduced power and feel. On one cold ride, this one dude popped the
plastic brake line from squeezing so hard. Since then, he switched to
some kind of steel or steel braided type line.

Chris Nelson said:

On the colder days(below 25 F), my hydraulic cronies complain of
reduced power and feel. On one cold ride, this one dude popped the
plastic brake line from squeezing so hard. Since then, he switched to
some kind of steel or steel braided type line.

Wrong type of brake fluid for winter use, or what is the source of
the problem?

On Sat, 27 Jan 2007 10:57:02 GMT, John Bucsek <[email hidden]>

Quoted message said:

and changing brake pads is a lot easier than on rim brakes.

One thing that puts me off disk brakes is too large a number of
diferent disk brake pads, which are intercompatible, while with any
kind of rim brake, just about any kind of brake pad I can get my hands
is bound to work with my rim brakes, either Vs, calipers, or
cantilevers.

How can be confident that the shape and size of disk brake pads I
choose now, will still be available in a few years time? (I wouldn't
be surprised if V-brake pads disapear, but I trust caliper pads will
always be available - for their weight advantage).

Ride your 2 wheels, but in order to ride them yet another day!
bbb

Chris Nelson said:

jim beam said:

Sticky Wicket said:

I am looking at getting a MTB at around the Deore LX level. Many bikes at
this level use disk brakes. A number of years ago the general consensus
seemed to be that these where heavier, more complicated, put extra strain on
wheels, and did not work as well as cantilevers except in very muddy
conditions. Has this changed to any degree since?
Stickystop listening to retrogrouches and try them. if you're not prepared to

put up with better braking, better wear in the wet, better bent wheel
tolerance, better performance in the wet and [with hydraulics] better
modulation, then yes, cantilevers are for you.

Ditto.

Except I use mechanical disks(BB7s) and still feel that they modulate
better than cantilever. I haven't converted to hydraulics because they
tend to be more problematic, especially in the cold weather conditions
in which I ride.

maybe ice in the caliper? it's not brake fluid - that freezes /way/
below zero [<-40C]. should flush your fluid annually if using
glycol-based fluids.

Quoted message said:

Mechanicals are heavier, by as much as half a pound,
but I did cut down on Twinkie consumption to compensate.

Chris

On Fri, 26 Jan 2007 18:56:17 GMT, Sticky Wicket <[email hidden]> may

have said:

I am looking at getting a MTB at around the Deore LX level. Many bikes at
this level use disk brakes. A number of years ago the general consensus
seemed to be that these where heavier, more complicated, put extra strain on
wheels, and did not work as well as cantilevers except in very muddy
conditions. Has this changed to any degree since?

Opinions vary.

The weight issue remains. Most disc setups are heavier than common
V-brake setups. Whether this is important is rider-dependent. I
should note that old-style cantis are no longer common on current
models.

The wheel-strain issue was always a red herring. The wheels can take
it.

Performance isn't a globally-addressable issue. Some disc brake
setups work every bit as well, and some every bit as badly, as some
V-brake setups. Most work *acceptably*, and most work better than rim
brakes when applied in conditions where water/dirt mud with a
lubricating capacity significantly contaminates the system. If this
functionality is important to you, then the disc has an advantage.

Rim brakes wear out the wheel rims (eventually), and the pads more
often. Disc brakes wear out the discs (slowly) and pads (sometimes
with distressing speed). Discs are easier to change than rims, so a
disc brake provides a small benefit in this regard.

Disc brake function places a stress on the front wheel which may,
under certain uncommon conditions, cause the wheel to be ejected from
the bike when the brake is applied. The real severity of this hazard
has not been officially determined to warrant action by the
manufacturers to reduce the likelihood of wheel ejection beyond what
is provided by the use of skewer retention shoulders at the fork ends.
Some feel that this is a known and proven danger which merits the
immediate recall of nearly all disc-brake-equipped bikes globally, but
this view is not widely shared. You should decide for yourself if
this issue is critical to you after you read the available propaganda
and information from both sides.

Although the use of a disc brake on most wheels requires the
repositioning of the left hub flange somewhat toward the centerline of
the hub, the resulting change in spoke angle on that side does not
appear to have any significant drawbacks attached.

One seldom-discussed down side for disc brakes is lack of
standardization of the pad design. Given the less than stunning
record of parts availability for many bike assemblies in the past, it
can be expected that a fairly large percentage of disc brake pads
will, at some point, no longer be supplied by the original
manufacturer. Unfortunately, because of the number of designs and the
relatively small number of units installed, it's quite likely that the
aftermarket suppliers will fail to provide replacements for some
models of disc brake, rendering those useless when the pads wear out.
This mitigates in favor of buying only those disc brakes whose pads
are already widely available and/or those disc brakes whose
manufacturers have a good track record when it comes to long-term
parts support.

I will note that at this time, none of my bikes is equipped with a
disc brake, although I have had them previously.

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.

Werehatrack <[email hidden]> wrote:

Pardon the top post, but... "excellent summary". That would sum up
anything I'd be likely to say as well (but now I don't have to). ;-)

Mark Hickey
Habanero Cycles
http://www.habcycles.com
Home of the $795 ti frame

Quoted message said:

Opinions vary.

The weight issue remains. Most disc setups are heavier than common
V-brake setups. Whether this is important is rider-dependent. I
should note that old-style cantis are no longer common on current
models.

The wheel-strain issue was always a red herring. The wheels can take
it.

Performance isn't a globally-addressable issue. Some disc brake
setups work every bit as well, and some every bit as badly, as some
V-brake setups. Most work *acceptably*, and most work better than rim
brakes when applied in conditions where water/dirt mud with a
lubricating capacity significantly contaminates the system. If this
functionality is important to you, then the disc has an advantage.

Rim brakes wear out the wheel rims (eventually), and the pads more
often. Disc brakes wear out the discs (slowly) and pads (sometimes
with distressing speed). Discs are easier to change than rims, so a
disc brake provides a small benefit in this regard.

Disc brake function places a stress on the front wheel which may,
under certain uncommon conditions, cause the wheel to be ejected from
the bike when the brake is applied. The real severity of this hazard
has not been officially determined to warrant action by the
manufacturers to reduce the likelihood of wheel ejection beyond what
is provided by the use of skewer retention shoulders at the fork ends.
Some feel that this is a known and proven danger which merits the
immediate recall of nearly all disc-brake-equipped bikes globally, but
this view is not widely shared. You should decide for yourself if
this issue is critical to you after you read the available propaganda
and information from both sides.

Although the use of a disc brake on most wheels requires the
repositioning of the left hub flange somewhat toward the centerline of
the hub, the resulting change in spoke angle on that side does not
appear to have any significant drawbacks attached.

One seldom-discussed down side for disc brakes is lack of
standardization of the pad design. Given the less than stunning
record of parts availability for many bike assemblies in the past, it
can be expected that a fairly large percentage of disc brake pads
will, at some point, no longer be supplied by the original
manufacturer. Unfortunately, because of the number of designs and the
relatively small number of units installed, it's quite likely that the
aftermarket suppliers will fail to provide replacements for some
models of disc brake, rendering those useless when the pads wear out.
This mitigates in favor of buying only those disc brakes whose pads
are already widely available and/or those disc brakes whose
manufacturers have a good track record when it comes to long-term
parts support.

I will note that at this time, none of my bikes is equipped with a
disc brake, although I have had them previously.

Werehatrack said:

....Disc brake function places a stress on the front wheel which may... cause the wheel to be ejected from the bike when the brake is applied. ...reduce the likelihood of wheel ejection...by the use of skewer retention shoulders at the fork ends.

If the dropouts were symmetrically aligned with the axis of the fork legs a really neat and simple solution would be to simply turn the fork legs around. With the caliper on the front side of the fork as opposed to the rear heavy braking would simpy force the wheel deeper into the dropouts. It'd look a bit odd, but I can't see any drawbacks.