Joe, I'm sorry but I don't see much contradiction. My primary objection is to two brakes operated by one lever. We have found one solution (three separate levers set up so you can't do both rears at the same time) to work for us. Your preference still uses three separate levers, but chooses one that can be set to exert constant (?) pressure as a drag brake.
I can't remember any descents longer than 1000' on our tandem. The longest was the rather steep and windy Mohonk Mt. descent in NY state. That was about the last time that Beloved Spouse controlled the rear drum and I had the two rim brakes. We were going too fast to be able to talk, and I could never tell when she would activate the disk, but I quickly learned that it could be in a turn. I'm sure that the paper label on the disk was charred when I checked at the bottom of the hill, and I believe that the disk was warped. But, we're still happily married some 25 years later, and she still had the gear shifters on her handlebars.
By the way, if I recall correctly the Pederson was a "servo" brake, set up so that the initial contact of brake to rim tended to draw the pads in closer and increase the pressure. So, what Joe B-Z is saying about hand power is Real Important. BTW, CLB had a rather elegant "servo," accomplished by having the pivots pointed in toward the (front) wheel.
harvey sachs mcLean va
Joseph Bender-Zanoni wrote:
> In some contradiction of Harvey, I think it is a good idea to be able
> to operate both rear brakes at the same time. Having a drum or disk
> brake as a drag brake, to take the heat load on long decents is a good
> idea if you ride in any kind of mountains. That being said, I have
> yet to implement it. I am thinking of a goofy looking stem shifter as
> I already have barcons. I went out on the tandem with my wife two
> weeks ago and the two cable front/rear Mafac lever, even though
> perfectly set up, just requires too much hand pressure. That's with a
> Pederson front and Mathhauser shoes on Mafac cantilevers so I don't
> know the next upgrade except my hands.
>
> Joe Bender-Zanoni
> Great Notch, NJ
>
>
> Harvey M Sachs wrote:
>
>> With all due respect, I've only seen one application where
>> controlling two brakes with one lever seemed appropriate. The rider
>> of that bike was one-handed.
>>
>> IMHO, in all other cases there are just too many compromises to be
>> made. 1) One lever controlling both rim brakes. Obviously impossible
>> to modulate relative force for better control on long grades, curves
>> and turns, etc. Since front brake is able to do more speed
>> reduction, want it to contact first and exert more force. But, if so
>> set up, will wear its pads more quickly, so vigilant and frequent
>> maintenance is required. 2) (mostly tandems) One lever controlling
>> front rim brake, dual-cable lever controlling both rim brakes. In
>> general, leverage (cable take-up) varies between rim brakes and hub
>> brakes, so one or the other will do next-to-nill work if actuated by
>> same lever with same travel for both.
>> If everything is working as you imagined it would, you can get into
>> real trouble. One day in Corvallis Oregon on a friends Jack Taylor
>> tandem, I got in trouble wrt oncoming car in a right turn situation.
>> So, I hit all the brakes (two cantis on dual lever, drum on the
>> other). Predictable result in a turn: rear wheel, "benefitting" from
>> two brakes and light load, locked up, so rear could slide nicely
>> toward the car.
>>
>> Our preferred solution is pretty simple: rim brakes separately
>> operated by conventional single-wire road levers. Auxiliary (hub)
>> brake operated by tourist lever mounted very low on right bar. This
>> makes it impossible to operate both rear brakes at the same time, but
>> get excellent modulation of rear hub brake by using it while riding
>> on the drops.
>>
>> So, that's personal preference and reasons, I promise not to be a
>> nanny if your views differ.
>>
>> harvey sachs
>> mcLean va
>>
>> Geoff,
>> The twin-cable MAFAC levers on my tandem are exactly the
>> same shape as an ordinary, single cable lever. So you really
>> can only mount them on the "hook" of the handlebar. I suppose
>> you could try modifying the actual lever portion of the piece,
>> but in that case, I wonder if you would get sufficient leverage
>> to properly operate the brakes.
>> Best of luck with the project,
>> Fred Rednor - Arlington, VA (USA)
>>
>> --- geoff duke <g.duke@civenv.unimelb.edu.au> wrote:
>>
>>
>>>> I am wondering if anyone can tell me if a Mafac twin cable
>>>> tandem brake lever would work if it were placed on the top of the
>>>> handlebars.Like a cyclocross lever.Would it be able to work
>>>> on the flat section of bar or do they need to be on the bends like
>>>> other levers.Thinking about setting up a single speed bike with
>>>> canti's front and rear with one lever and considering that there
>>>> would be a good place for it.Sorry if this question is a bit clunky
>>>> but
>>>> hoping for an answer,
>>>> Geoff Duke Melbourne Australia