Question about brakes

Hello newsgroup,


as my bike is wearing up in some expensive parts,
I am thinking about building up a new one.

Especially I am thinking to use disc brakes
instead of rim-grinders.

Everybody tells me to get hydraulic ones,
and I testet a bile equipped with such brakes
(a $ 1000 29er) in a big sports shop - they were
horrible, undoseable, either were open or blocked.

I can well imagine that in such shops, assembly
is not done by good mechanics.

On the other hand, I can't just imagine what is bad
about disc breaks operated via cable (unless you let
it rust). Is there a design flaw, or what is the
cyclists' aversion against them about?

Does anyone in real live drive with such brakes
and can tell me honestly about it?

I am not a downhill racer, and V-brakes would do
from the point of performance, but they destroy
the rims which I see as essential parts, not as
wear-off crap.



Thanks,


jk



--
no sig

On Saturday, May 17, 2014 5:41:58 PM UTC-4, Jakob Krieger wrote:
Hello newsgroup,





as my bike is wearing up in some expensive parts,

I am thinking about building up a new one.



Especially I am thinking to use disc brakes

instead of rim-grinders.



Everybody tells me to get hydraulic ones,

and I testet a bile equipped with such brakes

(a $ 1000 29er) in a big sports shop - they were

horrible, undoseable, either were open or blocked.



I can well imagine that in such shops, assembly

is not done by good mechanics.



On the other hand, I can't just imagine what is bad

about disc breaks operated via cable (unless you let

it rust). Is there a design flaw, or what is the

cyclists' aversion against them about?



Does anyone in real live drive with such brakes

and can tell me honestly about it?



I am not a downhill racer, and V-brakes would do

from the point of performance, but they destroy

the rims which I see as essential parts, not as

wear-off crap.







Thanks,





jk







--

no sig

Some people love cable actuated disc brakes whilst others despise them and prefer V-brakes or even cantilever brakes. Do V-brakes where down rims so quickly that the V-brakes are a problem for you?

Cheers

- Sir Ridesalot / Sat, 17 May 2014 23:57:49 +0200


Some people love cable actuated disc brakes ...

So there are survivers using these brakes? )

... whilst others despise them ...

Reading in MTB forums, they all seem to despise them.

... and prefer V-brakes or even cantilever brakes.

I understand that the discs laying more or less open
habe some chance of getting bent.

Do V-brakes where down rims so quickly that the V-brakes
are a problem for you?

Well, it seems canti/V mounting points are getting
out of fashion with frame-builders, so an accessory
construction would be needed. Or I'd have to use the
very old type held with one screw -
both not really top engineering.

From technical view, when I compare how a hydraulic
motorbike brake is made (with reservoir and reinforced
thick tubes), it is hard for me to trust the filigran
hoses used with bikes. On the other hand, cable actuated
systems have this bad reputation among cyclists (may be
induced by magazines who copy the manufacturers' texts?) -
I am unsure of what system to use.



jk




--
no sig

Strange that you find hydraulic disk brakes undoseable. The shop must have done something wrong. Mechanical disbrakes are fine though. I use both. I changed from mechanical to hydraulic diskbrakes on my crossbike. The only reason for that was that the hydraulic disbrakes require less force. I can get full braking power riding on the hoods, the default position for a crossbike off road.

Lou

- Lou Holtman / Sun, 18 May 2014 00:27:04 +0200

Thanks for your reply.

Strange that you find hydraulic disk brakes undoseable.
The shop must have done something wrong.

I was talking about _one_ bike I tested in this shop,
and I can't imagine that even cheap brakes (what I
wouldn't assume on a $ 1000 bike) have such a poor
characteristic by construction.

I didn't test another model because the salesman was
kind of unhappy with me not buying immediately.


From cars, I know that pistons can block and
pad-carriers can key on the housing - if the power
needed to move these parts is higher than what would
be needed for smooth braking ...
as soon as it moves at all, it will block.

May be they pressed in the pads with brutal force.


Mechanical disbrakes are fine though. I use both.

Ok, so I'll still consider this.


I changed from mechanical to hydraulic diskbrakes on my crossbike.
The only reason for that was that the hydraulic disbrakes require less force.

I understand. You don't have to be in the optimal
position to pull the lever, don't have to change grip.

Seems not to be my issue - so if built and adjusted well,
a cable-system is ok.



jk



--
no sig

On Saturday, May 17, 2014 3:27:04 PM UTC-7, Lou Holtman wrote:
Strange that you find hydraulic disk brakes undoseable. The shop must have done something wrong. Mechanical disbrakes are fine though. I use both. I changed from mechanical to hydraulic diskbrakes on my crossbike. The only reason for that was that the hydraulic disbrakes require less force. I can get full braking power riding on the hoods, the default position for a crossbike off road.



Lou

What brakes/levers are you using?

I commute daily on a mechanical disc bike. The brakes are super-simple, easy to maintain and stop very well (Avid BB7s). The are superior to rim brakes in wet weather, and the only drawback is the expense of replacement pads and that pads have to be replaced more frequently (but rims don't). I wouldn't bother with hydraulics because of the complexity and having to wrestle with the pads if I hit the lever with the wheel out during a flat change. Also, you have to dump a bunch of money if you want hydraulic and STI -- or Di2. Hydraulics, however, are more powerful and do not have the cable issues which result in a less positive rear brake. Pad adjustment is automatic. On a mountain bike, I would probably opt for hydraulics.

-- Jay Beattie.

Jakob Krieger wrote:
:Hello newsgroup,


:On the other hand, I can't just imagine what is bad
:about disc breaks operated via cable (unless you let
:it rust). Is there a design flaw, or what is the
:cyclists' aversion against them about?

The big advantage of good hydrualic disks over cable ones is that
the pad adjustment is automatic. Mechanical disks require adjusting
the pads periodically. Depending on the particular brake, that can
range from just an annoyance (BB7s, for instance, turn two knobs a
couple clicks every so often. Usually doesn't require tools.) to a
pain (cheap junk and old designs). Same process makes pad replacement
dead easy on hydraulics. MTB can kill a pair of pads in a single
afternoon, so automatic adustment matters to them. Road use, not so
much. Hydraulics also have a bit better modulation, if they're set up
right, and might require a little less force to operate. I don't care
about the modulation, what my BB7s have is superior to cantis or almost
all caliper brakes. And the force issue isn't an issue: I can get max
braking force with two fingers from the hoods.

I wouldn't pay a premium to get hydraulic disks, but if they were
avaialbe on a bike I liked (and since I ride bikes with drops, they're
not really), and were a good model, I'd take them.

--
sig 37

On Sat, 17 May 2014 23:41:58 +0200, "Jakob Krieger"
wrote:

Hello newsgroup,


as my bike is wearing up in some expensive parts,
I am thinking about building up a new one.

Especially I am thinking to use disc brakes
instead of rim-grinders.

Everybody tells me to get hydraulic ones,
and I testet a bile equipped with such brakes
(a $ 1000 29er) in a big sports shop - they were
horrible, undoseable, either were open or blocked.

I can well imagine that in such shops, assembly
is not done by good mechanics.

On the other hand, I can't just imagine what is bad
about disc breaks operated via cable (unless you let
it rust). Is there a design flaw, or what is the
cyclists' aversion against them about?

Does anyone in real live drive with such brakes
and can tell me honestly about it?

I am not a downhill racer, and V-brakes would do
from the point of performance, but they destroy
the rims which I see as essential parts, not as
wear-off crap.



Thanks,


jk

I suspect that your hydraulic brakes weren't adjusted correctly but
also I've ridden cable operated disk brakes that worked fine. I would
think that either would work well.
--
Cheers,

John B.
(invalid to gmail)

On Sunday, May 18, 2014 3:44:34 AM UTC+2, jbeattie wrote:
On Saturday, May 17, 2014 3:27:04 PM UTC-7, Lou Holtman wrote:

Strange that you find hydraulic disk brakes undoseable. The shop must have done something wrong. Mechanical disbrakes are fine though. I use both. I changed from mechanical to hydraulic diskbrakes on my crossbike. The only reason for that was that the hydraulic disbrakes require less force. I can get full braking power riding on the hoods, the default position for a crossbike off road.







Lou



What brakes/levers are you using?

The new Shimano ones. More and more roadbikes are offered with these brakes.. Just got the last copy of TOUR magazin. A test is in of a couple of thes bikes. Didn't read the article yet. Comes with Di2 by the way.

My crossbike on the first ride:

https://picasaweb.google.com/1010765...34670788893122

Lou

I have used Magura's hydraulic rim brakes on my Utopia for five or years now and they are very progressive, what you call doseable, Before that I used Shimano roller brakes on a Trek Benelux Di2 bike.and they were good too, but you had to pay attention because they could be sharp, Before that, on a Gazelle I had a cheap cable-operated disc brake and I know exactly what you mean: it was either on or off with no in between. I hated it even more for constantly chewing up brake pads and for constant demands on my time to adjust the bloody thing. Magura rim hydraulics are fit and forget, zero service, adjustment, from the handlebar, every few years. Give manual discs a miss.

Andre Jute