Here's my take: Our old tandem Mary and I rode around on was a Campy equiped
Gitane 531 frameset with Clement Strada 66 sew-ups.
We rode it for pleasure and not loaded touring.
Brakes were Campy Record.Our combined weight was about 270 US pounds.
Going about 40 plus on downhills and slower speeds on the flat never gave us
a stopping problem with this normal set up.
I have set up, repaired, fixed, and fit a lot of couples on their tandems.
Whether SINGLE or TANDEM, I would NEVER set the front brake to actuate
before the rear when both brakes were on one handle! PERIOD!
Your thoughts are nice but your logic is flawed.
This is a prime example of counter intuitive mechanical execution.
The object of the braking system is to stop without losing control.
The front brake stops radically faster than the rear because of weight
distribution, cable length, housing compression, etc.
Ergo Bibamus. whoops, wrong salon.
Ergo: Apply the REAR brake just enough sooner to counteract the front lunge,
keep you on the saddle better and prevent wheel / bike sliding possibility
by the "drag" action of the rear brake.
Many of the tandem riders had to figure out how the steerer and stoker
psyche / mentalities complimented each other and arranged the brakes
accordingly.
Domestic tranquillity sometimes comes with compromising a little.
Some couples had two brakes some three and others four.
Double caliper, disc, drum or combos with any lever combo, take your pick
whatever worked best for the couple so they became a duo and not a duel.
Communication was the key.
Some of the couples had shift and or brake levers on rear and or front and
worked it out.
Most couples agreed that riding the brakes all the way downhill was not
good, harder slow down , keep speed where it was wanted, let bike roll,
apply brakes, and make it easier on hands and equipment.
Think about it, on a fixed gear, the front brake only will flip you over if
applied too abruptly. So you slide your butt back some and backpedal to keep
you balanced.
Nez Pas?
It's the same on a tandem. The weight on the back holds the bike a little
more stable but two riders sliding forward is a negative desired force. so
the REAR brake has to brake just a little sooner to maintain better
integrity.
That's my humble opinion.
Ted Ernst
Palos Verdes Estates
CA USA
<classicrendezvous@bikelist.org> Sent: Wednesday, August 02, 2006 6:33 PM Subject: Re: [CR]Mafac two cable brake lever question
> 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