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Discussion Starter · #1 ·
I'm wondering how this would work out. Generally, modulation is a lever design function and improved power can be from either improvements in the lever or the caliper. The Question about 7900 is "does the improvement in power come from the lever or the caliper"

I like really powerful brakes (for long steep decents) but also like good modulation. It took the mountian biking industry about 15 years to get this combination figured out for rim brakes and road bikes have a ways to go.

We heard the brake lock up argument many times in the early 90's and I doubt that any mountain biker who went through that would buy into it now because we quickly adapted to each new generation of more powerful brakes.

In the end, this is pretty much a question of cable pull distance. Which system (7900 or R11) pulls the least amount of cable for identical lever travel?
 

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I'm thinking you might end up wondering for a while.
I just don't think that the Campy users will run 7900 brake caliper in their system just like 7900 users probably will not run Campy caliper.
Whatever the distance travel is I can't imagine one would be so much better that the users will mix the components....but I could be wrong.
 

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My rain bike has 2009 Centaur Ergos and 2008 Shimano long reach brakes (Ultegra level). Thing stops on a dime, likely due to the dual pivots front and back. Better than my 2008 Record (dual front, single rear) setup. Tougher to modulate tho..
 

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Good question you bring up, but: "HUH!?"

Really can't imagine someone actually testing it out. It'd be like being a Coca-Cola delivery driver dressed to the socks in Pepsi gear.

It actually makes me wonder if anyone whose using a non-Campy/Shimano brake system (i.e. ZeroGravity or whoever else makes brakes) could give an opinion (?...)
 

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Discussion Starter · #5 ·
I'm a bit amused by some of the responses. As a long time mountain biker turned roadie, I will never give a crap who makes components--only criteria is they be the best, most durable available. For years Shimano made many good components but absolute crap for mtb brakes. Prior to V brakes, only Freds used Shimano brakes.

If some combination of 7900 and Campy provides the best power and modulation, that is what makes sense to use. I'm convinced that the brake pivot point on campy 11 brifters is in a better design location than on Shimano 7900. If I find out that 7900 calipers provide more power, that is what I'll use. I would feel stupid putting brand consistency or loyalty above performance.

As close as I can tell, if campy has a weakness, it is in their brakes' stopping power. I hoping that someone has tried the campy brifters with 7900 calipers and can provide some insight so I can avoid buying both brands of calipers to find out.
 

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As close as I can tell, if campy has a weakness, it is in their brakes' stopping power. I hoping that someone has tried the campy brifters with 7900 calipers and can provide some insight so I can avoid buying both brands of calipers to find out.
Do you really think that? My 2006 Centaur brakes stop me just fine. I am actually damn impressed with how well these brakes work. I think these work as well for my road bike as my hydraulic discs do on my mountain bike.

Oh...and I use Centaur shifters with generic Nashbar brakes on my rain bike...stops just fine as well.
 

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SwiftSolo said:
I'm a bit amused by some of the responses. As a long time mountain biker turned roadie, I will never give a crap who makes components--only criteria is they be the best, most durable available. For years Shimano made many good components but absolute crap for mtb brakes. Prior to V brakes, only Freds used Shimano brakes.

If some combination of 7900 and Campy provides the best power and modulation, that is what makes sense to use. I'm convinced that the brake pivot point on campy 11 brifters is in a better design location than on Shimano 7900. If I find out that 7900 calipers provide more power, that is what I'll use. I would feel stupid putting brand consistency or loyalty above performance.

As close as I can tell, if campy has a weakness, it is in their brakes' stopping power. I hoping that someone has tried the campy brifters with 7900 calipers and can provide some insight so I can avoid buying both brands of calipers to find out.
hi swiftsolo,

the new campy11 brifters will 'enhance' the braking power, provide better modulation as well. the levers are redesigned, the shape of the ergo levers, especially the curve section on the levers reduces the travel distance while braking is applied when your hands are on the hoods. significant difference comparing this with 10s.

being a convert from 7800 to Campy 10s to Campy 11s, i would say D/Ace offers top class braking power, there is no denying about that. nevertheless combination of current 11s shifters and Campy calipers offers better modulation, therefore better control overall.

ride safe.

cheers
 

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WHY???

I have no problems whatsoever on my 2001 Campy Record shifters/brakes. I'm a big guy (210 lbs) and fly down mountain descents at upwards of 50mph...no problems even in panic situations.

I'll let you know about the new 11 sp Super Record after I pick up my newly built up 595 Ultra
 

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Discussion Starter · #9 ·
Maverick said:
hi swiftsolo,

the new campy11 brifters will 'enhance' the braking power, provide better modulation as well. the levers are redesigned, the shape of the ergo levers, especially the curve section on the levers reduces the travel distance while braking is applied when your hands are on the hoods. significant difference comparing this with 10s.

being a convert from 7800 to Campy 10s to Campy 11s, i would say D/Ace offers top class braking power, there is no denying about that. nevertheless combination of current 11s shifters and Campy calipers offers better modulation, therefore better control overall.

ride safe.

cheers
Thanks for the good input. It seems clear that the lever design on Campy 11 is better than on 7900 (for braking from the hoods) and you seem to substantiate that view.

We do some 3000' decents on steep winding roads at 12 to 15%. Hand fatigue gets to be a problem. I remember the same problem in the early days on my mtb (before discs). We now have brakes that modulate very well and can be locked up easily with one finger (if you decide you want to). Contrary to popular belief, we never inadvertantly lock them up--even in an emergency situation. Obviously, all road riders adjust for wet road conditions without depowering our brakes and I just don't encounter people who lock them up because the roads are slick.

I should be able to figure this out with some simple physics but campy 11 is scarce in our area.

Thanks again
 

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info...

The new brake levers have the same 4:1 actuation ratio as before, so it really applies no more force than before. The brake lever is about 20% longer, so that requires a little more travel.

I do a lot of mountain descents, but I never ride the brakes. I only apply the brakes before a corner to reduce speed and perhaps a little rear braking for modulation in a corner.

The rear brake is deliberately weaker to avoid rear wheel lockup, but it can still be done on a steep descent.
 

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Discussion Starter · #11 ·
C-40 said:
The new brake levers have the same 4:1 actuation ratio as before, so it really applies no more force than before. The brake lever is about 20% longer, so that requires a little more travel.

I do a lot of mountain descents, but I never ride the brakes. I only apply the brakes before a corner to reduce speed and perhaps a little rear braking for modulation in a corner.

The rear brake is deliberately weaker to avoid rear wheel lockup, but it can still be done on a steep descent.
Trolling today are we?
 

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no...

SwiftSolo said:
Trolling today are we?
Just reporting the facts. Campy lists the distance from the center of the brake lever curve to the pivot as 76mm on the old levers and 88mm on the new ones. The distances from the pivot to the brake cable are 19 and 22mm, respectively. Both are the same 4/1, so there is not increase in braking force from the hooks.

Riding the brakes on a long descent is unwise, unless the road is so rough that you risk damage to the tires and rims from potholes. If I ever get on a road like that, I avoid it in the future.
 

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Discussion Starter · #13 ·
C-40 said:
Just reporting the facts. Campy lists the distance from the center of the brake lever curve to the pivot as 76mm on the old levers and 88mm on the new ones. The distances from the pivot to the brake cable are 19 and 22mm, respectively. Both are the same 4/1, so there is not increase in braking force from the hooks.

Riding the brakes on a long descent is unwise, unless the road is so rough that you risk damage to the tires and rims from potholes. If I ever get on a road like that, I avoid it in the future.
Ok,
I'll play along!

Gee, thanks for the nugget of wisdom ("riding the brakes" is "unwise").

The distances listed are substantially irrelevant without knowing the relative angle between the lever axis and the cable pull pivot / lever pivot axis. If that angle has increased it is likely that both braking power and modulation has improved at the expense of total travel (not really any expense at all if your wheels are true).

The pull ratio changes dramatically as the lever travels toward "max on". For all practical purposes, it can not be linear using a single pivot brake levers.

The MTB industry debunked the "brake lock up theories" 20 years ago but they persist in road biking. Yet, each new generation of road components tout better braking. Ten years from now road brakes will be far more powerful and have far better modulation. My objective is to jump as far ahead as possible. Any reduction in arm pump on long, steep, twisting decents can only be a good thing.

Finally, we likely ride different downhills and therefore have different needs. This seems to show up on both braking and gearing threads.
 

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angles...

The angles have not changed significantly and the brakes have not changed at all. The reach to the brake lever from the hooks is a few millimeters closer to the bar, but Campy levers have a large amount of excess travel available, so that is not an issue. The brake cable tension can be set to start the braking action quickly, or allow quite a bit of travel before any braking action occurs.

The fact that you believe the 4/1 actuation ratio to be irrelevant tells me you're no engineer. When the brake lever only moves 10-20 degrees and only a fraction of that amount is actual braking, the pull ratio does not change radically at max braking.

FWIW, I make a modification to the ergo body that prevents the brake lever from opening fully, reducing the reach to the brake levers from the hooks by at least 10mm (for my short fingers). I still have plenty of travel left to provide adequate rim to pad clearance and avoid the finger lever touching the bars under full braking.
 

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Discussion Starter · #15 ·
C-40 said:
The fact that you believe the 4/1 actuation ratio to be irrelevant tells me you're no engineer. When the brake lever only moves 10-20 degrees and only a fraction of that amount is actual braking, the pull ratio does not change radically at max braking.

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Aw, it continues.
Not sure this is worth it because there seems to be a comprehension problem.

First: what I actually said was "The distances listed are substantially irrelevant without knowing the relative angle between the lever axis and the cable pull pivot / lever pivot axis".
A bit different than "you believe the 4/1 actuation ratio to be irrelevant "

Second, your observation about what this "tells you" is as accurate as your conclusion. If the cable attachment pivot is 40 degress forward of the lever pivot (as measured from the lever plane), It will be pulling half as much cable at the final degree of the lever travel as it would starting 20 degrees aft. That would equate to half as much power--everything else being equal and assuming your 20 degrees of total pull.

Shimano uses a backwards approach and does indeed have the cable attachment aft of the plane of the lever. That results in more cable pull (less additional power--poorer modulation) as the lever approaches max-on. From pictures, it would appear that Campy uses the opposite approach and attaches the cable pivot forward of the plane of the lever and pivot axis resulting in an increased rate of power as the lever approaches max-on. It would likely follow that Campy has better modulation.

My guess is that the reason brake evolution is slow relates to a$$ protection. The theory being that exceeding the industry standards by very much (regarding braking power) may lead to litigation. The difference is that the mtb industry started in this process near its' inception and pioneered the debunking of myths that somehow still persist with road riders. Easy, one finger lock-up has become the mtb industry standard.

Incidentally, there will be a small amount of truth in those myths for those who hop on a bike with 4 times the braking power for the first time. It takes about 10 minutes to adjust to the increased power and to find out where lock up occurs.
 

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even more...

I'd say that you are overthinking this. FWIW, Campy claims more braking power from the hoods due to the change in the location of the pivot point relative to the hoods, and better modulation but no increase in max braking power from the hooks, compared to their old levers, since the actuation ratio remains the same.

If you hold a straight edge along the curve lowest point in the brake lever curve to the center of the pivot point, the brake cable attachment point is located behind that line, but not a large amount.

I've logged about 1,000 miles on the new brake levers and can't say I notice a big difference. I'm sure the braking from the hoods is more powerful, but I never do any critical braking from the hoods, so it's not a big issue.
 

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Discussion Starter · #17 · (Edited)
C-40 said:
I'd say that you are overthinking this. FWIW, Campy claims more braking power from the hoods due to the change in the location of the pivot point relative to the hoods, and better modulation but no increase in max braking power from the hooks, compared to their old levers, since the actuation ratio remains the same.

If you hold a straight edge along the curve lowest point in the brake lever curve to the center of the pivot point, the brake cable attachment point is located behind that line, but not a large amount.

I've logged about 1,000 miles on the new brake levers and can't say I notice a big difference. I'm sure the braking from the hoods is more powerful, but I never do any critical braking from the hoods, so it's not a big issue.
Thanks for the input. Just sitting on a bike with campy 11 in a shop convinced me of the superiority of the location of the lever pivot pin relative to 7900 (for braking from the hoods). My observation regarding campy lever pivot pin locations was made from rather obilque pictures and assumed that the two pins that penetrate the lever were the brake cable attachment and the lever pivot. It is likely an optical illusion that the top pin appears to be forward of the lower relative to the probable direction of cable pull.

My guess at this point is that the Shimano 7900 calipers with Campy 11 levers may well be the ticket to better braking. I'll try both and come back with a better answer.

I suspect that the brake cable is further from the caliper pivot pins on the 7900s (with pads against the rim and measured perpendicular to the cable). That would likely mean more powerful calipers.
 

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SwiftSolo said:
Thanks for the input. Just sitting on a bike with campy 11 in a shop convinced me of the superiority of the location of the lever pivot pin relative to 7900 (for braking from the hoods). My observation regarding campy lever pivot pin locations was made from rather obilque pictures and assumed that the two pins that penetrate the lever were the brake cable attachment and the lever pivot. It is likely an optical illusion that the top pin appears to be forward of the lower relative to the probable direction of cable pull.

My guess at this point is that the Shimano 7900 calipers with Campy 11 levers may well be the ticket to better braking. I'll try both and come back with a better answer.

I suspect that the brake cable is further from the caliper pivot pins on the 7900s (with pads against the rim and measured perpendicular to the cable). That would likely mean more powerful calipers.

I upgraded to from 10 to 11 speed but kept my Mavic SSC brakes. The longer levers make the modulation better from the drops but haven't made much difference from the hoods. Overall the braking is better.
 

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pivot locations...

The lower visible pin is the brake lever pivot, but the other one is not the brake cable attachment point, it's just the stop/quick release pin. The cable attachment is higher and further back, inside the ergobody.
 

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Discussion Starter · #20 ·
C-40 said:
The lower visible pin is the brake lever pivot, but the other one is not the brake cable attachment point, it's just the stop/quick release pin. The cable attachment is higher and further back, inside the ergobody.
C-40,
I found this "x-ray" view of the campy brifters today.

I was wrong in relating the increase in power to the lever plane because I was assuming that the lever plane was perpendicular to the direction of cable pull.

The good news is that the campy lever indeed works as I expected (starts at 75 degrees and decreases to 55 degrees) and provides increasingly more kgs of cable pull for each kg of lever pressure as the lever approaches "max-on". This is the opposite of Shimano which starts at about 120 degrees and approaches 100 degrees at "max-on". The Shimano lever will produce decreasing additional cable pull pressure per kg of lever pressure at "max-on".

The entire approach is an exact repeat of Shimano's approach to the mtb industry. Eventually the XTR and XT levers became very creative with a floating cable pull pin that moved toward the lever pivot pin as more pressure was applied. That did not happen until every other brake manufacturer kicked their butt. Even today, Shimano dominates the mtb components market except they've never regained their share of the mtb brake market.

That is not to say their brakes are weaker than Campy (from comments--they may be stronger). They simply have reverse modulation that keeps Freds from locking them up easily when they panic.

I ordered the entire record 11 group from Shinybike today. I'll get some 7900 calipers as well so I can sort this out. I'm pretty well convinced that the 7900 calipers are more powerfull than 11 calipers because of the depowering lever geometry that shimano uses.

There may be a question of adequate cable travel with the camp brifter / 7900 caliper set-up but I doubt it (I keep my wheels true). It will be fun to try it.
 
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