Speaking of Brakes

On 8/5/2017 8:42 PM, John B. wrote:

Are single pivot brakes actual less powerful then dual pivot? I had
always assumed that the ratio of the length of the arms on the cable
side of the pivot and the brake pads end determined the "power" of a
brake. Although admittedly I never gave it much thought other then
single pivot brakes seemed more difficult to get "centered".

Yes, dual pivot brakes have a higher mechanical advantage than single
pivot brakes. The difference is easily noticeable. As you'd expect,
they have less travel, so they can't clear an out of true rim as easily.

--
- Frank Krygowski

On Sunday, August 6, 2017 at 2:46:26 AM UTC+2, John B. wrote:
On Sat, 5 Aug 2017 14:43:16 -0700 (PDT), wrote:

On Saturday, August 5, 2017 at 1:00:41 PM UTC-7, AMuzi wrote:
On 8/5/2017 1:49 PM, wrote:
What struck me as weird is that we have pro racers putting hydraulic disc brakes on road bikes in pro races. These things are incredibly powerful and can easily lock wheels especially in less than perfect traction conditions.

In the meantime Campagnolo Record skeleton brakes have reduced their power on the rear brakes by going from a double pivot to a single pivot rear brake mechanism.

Ummm, aren't we at odds here?


Campagnolo also has road discs- the new Ergos can run
caliper or hydraulic disc.

Regarding calipers, Campagnolo single pivot rears are
lighter than DP yet sufficient to skid a rear wheel.
Sensible format IMHO.

My Redline aluminum cross bike has hydraulic discs on it and I would MOST definitely not get them again. That bike probably weighs about the same as my Colnago Dream HP which is the lightest of the series at about 19 lbs. Crashing down a hill a brake as powerful as a disc is asking for trouble.

Caught out in downpours I never had the slightest problem with rim brakes and listening to people talking about going deeper into a turn before having to put the brakes on makes me wonder if they think that they are world class MTB racers.

I read that TdeF riders and their ilk have been known to descend at
speeds of 100kph using rim brakes. I wonder whether if they had
Joerg's vaunted disks, would they be faster?
--
Cheers,

John B.

Everyone who has descended in the wet with rimbrakes and carbon rims know the answer.

Lou

On Sat, 5 Aug 2017 22:35:39 -0700 (PDT), wrote:

On Sunday, August 6, 2017 at 2:46:26 AM UTC+2, John B. wrote:
On Sat, 5 Aug 2017 14:43:16 -0700 (PDT), wrote:

On Saturday, August 5, 2017 at 1:00:41 PM UTC-7, AMuzi wrote:
On 8/5/2017 1:49 PM, wrote:
What struck me as weird is that we have pro racers putting hydraulic disc brakes on road bikes in pro races. These things are incredibly powerful and can easily lock wheels especially in less than perfect traction conditions.

In the meantime Campagnolo Record skeleton brakes have reduced their power on the rear brakes by going from a double pivot to a single pivot rear brake mechanism.

Ummm, aren't we at odds here?


Campagnolo also has road discs- the new Ergos can run
caliper or hydraulic disc.

Regarding calipers, Campagnolo single pivot rears are
lighter than DP yet sufficient to skid a rear wheel.
Sensible format IMHO.

My Redline aluminum cross bike has hydraulic discs on it and I would MOST definitely not get them again. That bike probably weighs about the same as my Colnago Dream HP which is the lightest of the series at about 19 lbs. Crashing down a hill a brake as powerful as a disc is asking for trouble.

Caught out in downpours I never had the slightest problem with rim brakes and listening to people talking about going deeper into a turn before having to put the brakes on makes me wonder if they think that they are world class MTB racers.

I read that TdeF riders and their ilk have been known to descend at
speeds of 100kph using rim brakes. I wonder whether if they had
Joerg's vaunted disks, would they be faster?
--
Cheers,

John B.

Everyone who has descended in the wet with rimbrakes and carbon rims know the answer.

Lou

I was wrong. They apparently not descending at 100 kph. It now seems
that speeds are a bit faster, 130kph.... (81 mph) with rim brakes.
http://tinyurl.com/ybnfoquu
--
Cheers,

John B.

On Sunday, August 6, 2017 at 11:20:18 AM UTC+2, John B. wrote:
On Sat, 5 Aug 2017 22:35:39 -0700 (PDT), wrote:

On Sunday, August 6, 2017 at 2:46:26 AM UTC+2, John B. wrote:
On Sat, 5 Aug 2017 14:43:16 -0700 (PDT), wrote:

On Saturday, August 5, 2017 at 1:00:41 PM UTC-7, AMuzi wrote:
On 8/5/2017 1:49 PM, wrote:
What struck me as weird is that we have pro racers putting hydraulic disc brakes on road bikes in pro races. These things are incredibly powerful and can easily lock wheels especially in less than perfect traction conditions.

In the meantime Campagnolo Record skeleton brakes have reduced their power on the rear brakes by going from a double pivot to a single pivot rear brake mechanism.

Ummm, aren't we at odds here?


Campagnolo also has road discs- the new Ergos can run
caliper or hydraulic disc.

Regarding calipers, Campagnolo single pivot rears are
lighter than DP yet sufficient to skid a rear wheel.
Sensible format IMHO.

My Redline aluminum cross bike has hydraulic discs on it and I would MOST definitely not get them again. That bike probably weighs about the same as my Colnago Dream HP which is the lightest of the series at about 19 lbs. Crashing down a hill a brake as powerful as a disc is asking for trouble..

Caught out in downpours I never had the slightest problem with rim brakes and listening to people talking about going deeper into a turn before having to put the brakes on makes me wonder if they think that they are world class MTB racers.

I read that TdeF riders and their ilk have been known to descend at
speeds of 100kph using rim brakes. I wonder whether if they had
Joerg's vaunted disks, would they be faster?
--
Cheers,

John B.

Everyone who has descended in the wet with rimbrakes and carbon rims know the answer.

Lou

I was wrong. They apparently not descending at 100 kph. It now seems
that speeds are a bit faster, 130kph.... (81 mph) with rim brakes.
http://tinyurl.com/ybnfoquu
--
Cheers,

John B.

On a curvy descend in the wet with carbon rims? I don't think so.
My grandpa smoked his whole life and he reached an age of 85. That is possible, but people who smoke are still stupid, ignorant or weak.

Lou

On 2017-08-05 15:25, wrote:
M We heard your description of a riding performance go no go once
before... I forget what....some time ago...n had the idea you were
moving slowly.


I have absolutely no clue what you are talking about now.


During my peak years 2 of us covered the county with the Pelton doing
race work...15-20


15-20mph? That's not racing, that is considered a normal traveling speed
among road bikes out here, myself included, sans peloton. The serious
guys like the boss at a client company are cruising along well above
20mph. Last time we rode together he kept it around 25mph and after
20mins of this my tongue was almost on the handlebar, too much for me.


My co rider was Hungarian pharmicist.


My last one was a chemist.

--
Regards, Joerg

http://www.analogconsultants.com/

On Sunday, August 6, 2017 at 2:20:18 AM UTC-7, John B. wrote:
On Sat, 5 Aug 2017 22:35:39 -0700 (PDT), wrote:

On Sunday, August 6, 2017 at 2:46:26 AM UTC+2, John B. wrote:
On Sat, 5 Aug 2017 14:43:16 -0700 (PDT), wrote:

On Saturday, August 5, 2017 at 1:00:41 PM UTC-7, AMuzi wrote:
On 8/5/2017 1:49 PM, wrote:
What struck me as weird is that we have pro racers putting hydraulic disc brakes on road bikes in pro races. These things are incredibly powerful and can easily lock wheels especially in less than perfect traction conditions.

In the meantime Campagnolo Record skeleton brakes have reduced their power on the rear brakes by going from a double pivot to a single pivot rear brake mechanism.

Ummm, aren't we at odds here?


Campagnolo also has road discs- the new Ergos can run
caliper or hydraulic disc.

Regarding calipers, Campagnolo single pivot rears are
lighter than DP yet sufficient to skid a rear wheel.
Sensible format IMHO.

My Redline aluminum cross bike has hydraulic discs on it and I would MOST definitely not get them again. That bike probably weighs about the same as my Colnago Dream HP which is the lightest of the series at about 19 lbs. Crashing down a hill a brake as powerful as a disc is asking for trouble..

Caught out in downpours I never had the slightest problem with rim brakes and listening to people talking about going deeper into a turn before having to put the brakes on makes me wonder if they think that they are world class MTB racers.

I read that TdeF riders and their ilk have been known to descend at
speeds of 100kph using rim brakes. I wonder whether if they had
Joerg's vaunted disks, would they be faster?
--
Cheers,

John B.

Everyone who has descended in the wet with rimbrakes and carbon rims know the answer.

Lou

I was wrong. They apparently not descending at 100 kph. It now seems
that speeds are a bit faster, 130kph.... (81 mph) with rim brakes.
http://tinyurl.com/ybnfoquu

Those numbers are not believable unless you're descending a cinder cone or ski slope. If you're even getting close to 80mph, you're not turning or braking -- it's a dead straight, long run-out.

With that said, dual-pivots on aluminum rims or aluminum brake track rims are more than adequate. On CF rims, things are a little more complicated, and on wet roads, I prefer discs.

My road discs are not scary, except the price of replacement pads. They modulate well, and after ride two, I was aware of the stronger braking force -- particularly rear braking.

Do I need them? No, not in the sense that I wouldn't stop otherwise, but discs in the PNW save rims and make life better in all the rain. On a dry weather bike, I prefer the simplicity of dual-pivots.

-- Jay Beattie.

On 2017-08-05 17:46, John B. wrote:
On Sat, 5 Aug 2017 14:43:16 -0700 (PDT), wrote:

On Saturday, August 5, 2017 at 1:00:41 PM UTC-7, AMuzi wrote:
On 8/5/2017 1:49 PM, wrote:
What struck me as weird is that we have pro racers putting
hydraulic disc brakes on road bikes in pro races. These things
are incredibly powerful and can easily lock wheels especially
in less than perfect traction conditions.

In the meantime Campagnolo Record skeleton brakes have reduced
their power on the rear brakes by going from a double pivot to
a single pivot rear brake mechanism.

Ummm, aren't we at odds here?


Campagnolo also has road discs- the new Ergos can run caliper or
hydraulic disc.

Regarding calipers, Campagnolo single pivot rears are lighter
than DP yet sufficient to skid a rear wheel. Sensible format
IMHO.

My Redline aluminum cross bike has hydraulic discs on it and I
would MOST definitely not get them again. That bike probably weighs
about the same as my Colnago Dream HP which is the lightest of the
series at about 19 lbs. Crashing down a hill a brake as powerful as
a disc is asking for trouble.


Why? I can make the front wheel on my MTB stop abruptly with one or two
fingers. Unless done deliberately (which happens) this can easily result
in an OTB crash or a front wheel wipe-out.

The fix is simple: Don't do that.


Caught out in downpours I never had the slightest problem with rim
brakes and listening to people talking about going deeper into a
turn before having to put the brakes on makes me wonder if they
think that they are world class MTB racers.

I read that TdeF riders and their ilk have been known to descend at
speeds of 100kph using rim brakes. I wonder whether if they had
Joerg's vaunted disks, would they be faster? -- Cheers,


They take a lot more risks than non-competition riders. Just look at
those finish phases where there are sometimes nasty mass crashes. Riding
at high speed just inches away from others, something I'd never do. TdF
riders also know that the medics will be there in seconds if they crash.
With us guys way out there on a lonely switchback road with no cell
coverage, different story.

Anyhow, with discs downhill sections can be ridden more aggressively
because they allow you to reach into the brakes later and decelerate
more abruptly before tight turns. Living in the hills I feel the
difference almost every time when I ride the MTB on streets. The MTB
corners poorly on asphalt but I can bomb towards the turn, go behind the
saddle and then reach in hard.

When it is raining the difference is huge. Rim brakes are no match at
all in the rain.

--
Regards, Joerg

http://www.analogconsultants.com/

On Saturday, August 5, 2017 at 5:42:20 PM UTC-7, John B. wrote:
On Sat, 05 Aug 2017 15:00:35 -0500, AMuzi wrote:

On 8/5/2017 1:49 PM, wrote:
What struck me as weird is that we have pro racers putting hydraulic disc brakes on road bikes in pro races. These things are incredibly powerful and can easily lock wheels especially in less than perfect traction conditions.

In the meantime Campagnolo Record skeleton brakes have reduced their power on the rear brakes by going from a double pivot to a single pivot rear brake mechanism.

Ummm, aren't we at odds here?


Campagnolo also has road discs- the new Ergos can run
caliper or hydraulic disc.

Regarding calipers, Campagnolo single pivot rears are
lighter than DP yet sufficient to skid a rear wheel.
Sensible format IMHO.

Are single pivot brakes actual less powerful then dual pivot? I had
always assumed that the ratio of the length of the arms on the cable
side of the pivot and the brake pads end determined the "power" of a
brake. Although admittedly I never gave it much thought other then
single pivot brakes seemed more difficult to get "centered".

Dual pivot brakes have longer pivots on both sides. Single pivots have equal length and short pivots. The single pivot acts sooner but for any given pressure on the levers exerts less pressure on the shoes.

On Saturday, August 5, 2017 at 7:48:12 PM UTC-7, Frank Krygowski wrote:
On 8/5/2017 8:42 PM, John B. wrote:

Are single pivot brakes actual less powerful then dual pivot? I had
always assumed that the ratio of the length of the arms on the cable
side of the pivot and the brake pads end determined the "power" of a
brake. Although admittedly I never gave it much thought other then
single pivot brakes seemed more difficult to get "centered".

Yes, dual pivot brakes have a higher mechanical advantage than single
pivot brakes. The difference is easily noticeable. As you'd expect,
they have less travel, so they can't clear an out of true rim as easily.

Yes, but it doesn't make a lot of difference since most of these brakes are limited by the seat stays anyway.

On Sunday, August 6, 2017 at 7:51:28 AM UTC-7, jbeattie wrote:
On Sunday, August 6, 2017 at 2:20:18 AM UTC-7, John B. wrote:
On Sat, 5 Aug 2017 22:35:39 -0700 (PDT), wrote:

On Sunday, August 6, 2017 at 2:46:26 AM UTC+2, John B. wrote:
On Sat, 5 Aug 2017 14:43:16 -0700 (PDT), wrote:

On Saturday, August 5, 2017 at 1:00:41 PM UTC-7, AMuzi wrote:
On 8/5/2017 1:49 PM, wrote:
What struck me as weird is that we have pro racers putting hydraulic disc brakes on road bikes in pro races. These things are incredibly powerful and can easily lock wheels especially in less than perfect traction conditions.

In the meantime Campagnolo Record skeleton brakes have reduced their power on the rear brakes by going from a double pivot to a single pivot rear brake mechanism.

Ummm, aren't we at odds here?


Campagnolo also has road discs- the new Ergos can run
caliper or hydraulic disc.

Regarding calipers, Campagnolo single pivot rears are
lighter than DP yet sufficient to skid a rear wheel.
Sensible format IMHO.

My Redline aluminum cross bike has hydraulic discs on it and I would MOST definitely not get them again. That bike probably weighs about the same as my Colnago Dream HP which is the lightest of the series at about 19 lbs. Crashing down a hill a brake as powerful as a disc is asking for trouble.

Caught out in downpours I never had the slightest problem with rim brakes and listening to people talking about going deeper into a turn before having to put the brakes on makes me wonder if they think that they are world class MTB racers.

I read that TdeF riders and their ilk have been known to descend at
speeds of 100kph using rim brakes. I wonder whether if they had
Joerg's vaunted disks, would they be faster?
--
Cheers,

John B.

Everyone who has descended in the wet with rimbrakes and carbon rims know the answer.

Lou

I was wrong. They apparently not descending at 100 kph. It now seems
that speeds are a bit faster, 130kph.... (81 mph) with rim brakes.
http://tinyurl.com/ybnfoquu

Those numbers are not believable unless you're descending a cinder cone or ski slope. If you're even getting close to 80mph, you're not turning or braking -- it's a dead straight, long run-out.

With that said, dual-pivots on aluminum rims or aluminum brake track rims are more than adequate. On CF rims, things are a little more complicated, and on wet roads, I prefer discs.

My road discs are not scary, except the price of replacement pads. They modulate well, and after ride two, I was aware of the stronger braking force -- particularly rear braking.

Do I need them? No, not in the sense that I wouldn't stop otherwise, but discs in the PNW save rims and make life better in all the rain. On a dry weather bike, I prefer the simplicity of dual-pivots.

Jay - do you normally ride at such a speed that heavy braking with any sort of brake is necessary?