Tandem Cycling - Mechanical brake splitter options

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View Full Version : Mechanical brake splitter options


truckin
04-07-06, 08:21 AM
Hi all,

I posted in this forum last year when I acquired a Trek T100 tandem (at that point I needed to know how to adjust the eccentric BB to tension the timing chain properly). I got responses very quickly that gave me exactly the information I needed, and we were able to get the tandem up and running with no problems- so thanks to everyone who responded to that post. Since then, I've mostly been lurking, learning about concerns specific to tandems.

I've searched the tandem forum as well as Google for the answer to my current question, and while I have found some threads referring to tandem brake splitters, most of what I see either refers to splitting lines for S&S-coupled tandems or other items that aren't quite what I'm looking for (to skip all the background detail of my post below and move to my question, see the final two paragraphs).

I'm looking into changing the gearing and brake setup on the bike, so I have a parts question. It currently has a drum brake on the rear and a rim brake on each wheel (the original cantis as best I can tell). The left-hand lever controls the drum brake, and while we don't use it much, we would like to retain it as we found it helpful occasionally when riding on a cross-country trip last summer. The right-hand lever controls both of the rim brakes. Both brake cables come to the lever and the head of each one fits into the crossbar inside the lever so that they're activated together. They are fine-tuned to engage in the front first and more strongly, then in the rear so as to prevent accidental locking of the rear and the resultant potential problems.

The bike had a six-speed freewheel on it which I have replaced with a seven-speed freewheel (I changed the bar-cons to friction mode to allow proper shifting). I have a spare set of RSX 7-speed brifters that I'd like to put on the bike (naturally I'll keep the bar-cons in the parts bin as spares). Since the existing right-hand lever controls both brakes, and I'd like to keep the drag brake as well, I need a splitter that will allow one STI brifter to control two calipers. I know that QBP has at least one item that fits the one-lever-to-two-brakes bill, but from the picture I saw of it in the catalog, I'm not sure that it would be the best option. It appears to be just a cylinder into which I assume each cable would run; there must be some sort of attachment like an allen screw to fasten them in, but I couldn't see it in the catalog image.

What I'm looking for, then, is recommendations from you esteemed tandemers as to what you have found to be most useful and reliable for this type of setup. If at all possible, please provide part numbers or names for easier identification.

Thanks in advance,

truckin


ElRey
04-07-06, 08:40 AM
If yer a rookie, take it to a shop. These are your brakes. No room for mistakes.

truckin
04-07-06, 08:47 AM
No, no worries there- I can hold my own as a wrench. Thanks for looking out for me, though!


gregm
04-07-06, 01:39 PM
The right-hand lever controls both of the rim brakes.

I have a spare set of RSX 7-speed brifters that I'd like to put on the bike (naturally I'll keep the bar-cons in the parts bin as spares).

truckin,

You are soooo close to the perfect set-up, and you have all of the parts already.

Install your RSX brifters. Ditch the brake splitter, and cable up front & rear brakes to the left & right brifters as normal.

Keep a barcon, and wire this up to the drag brake.

This is a very, very common setup for tandems, and for good reason, since it works very well. It also lets you use the drum brake very easily as a drag brake -- just push the barcon enough to dial in the amount of drag you want on a descent, and you're set.

-Greg

Retro Grouch
04-07-06, 04:44 PM
truckin,

You are soooo close to the perfect set-up, and you have all of the parts already.

Install your RSX brifters. Ditch the brake splitter, and cable up front & rear brakes to the left & right brifters as normal.

Keep a barcon, and wire this up to the drag brake.

This is a very, very common setup for tandems, and for good reason, since it works very well. It also lets you use the drum brake very easily as a drag brake -- just push the barcon enough to dial in the amount of drag you want on a descent, and you're set.

-Greg

That's what I would do too.

Michel Gagnon
04-07-06, 08:00 PM
The same splitter you already have could be used with STI, but I much prefer independent controls for the brakes.

A very common setup is the one described by GregM and explained here (http://sheldonbrown.com/tandem-brakes.html) by Sheldon Brown.

Most tourists to that because it allows them to "set and forget" their drag brake all the way through a long descent.

However, since I have a child stoker, relatively short but steep hills and lots of bumps and potholes, I went for a different system that can be seen here (http://www.mgagnon.net/velo/potence-double.en.shtml). I have three levers that work this way:
– the right lever controls the front rim brake (I prefer that setup);
– the top left lever controls the rear rim brake;
– the lower left lever controls the (rear) drag brake.

During a steep hill, I'll keep the lower left lever depressed all the time, but I will ease the pressure drastically when approaching potholes and crevasses. And I use the front brake for additional braking. If the need were to arise, I can use all three brakes at once, though I would need a much heavier stoker for that.

zonatandem
04-07-06, 10:45 PM
Michel's set-up is right on the money, but there's yet another choice . . . use the brifters for shifting and for the front/rear canties.
Mount the barcon on stoker bar and lead the brake wire to the drum brake. Stoker can brake, at your command; or stoker can set barcon as a drag brake for steep/long descents.
Keep on truckin'!

Pedal on TWOgether!
Rudy and Kay/zonatandem

truckin
04-08-06, 12:29 PM
That's why I read these forums! Thanks for the great ideas. GregM and RG, that's what I'll end up doing for our setup; and MG and zonatandem, thanks for the additional ideas. As my stoker prefers to just plain pedal and not worry about the driving aspect, I'll keep all the controls at my end, and I really like the set-and-forget concept for the drag brake. Let's hope I don't forget to un-set it at the bottom of the hills!

It didn't occur to me that I could use the barcon as a brake control, and while I have pored over many of Sheldon Brown's pages, I had not seen that one- very good information there.

Thanks again,

truckin

vosyer
04-08-06, 04:24 PM
We have one of our tandems set up with the stocker barend combination, another with the the thumb shifter combination - prefer the the thumb shifter combination. We have also seen two other combinations - a time trial lever in the barend postition and a top mount hand brake similar to those used on mountain bikes. Orginally I had diacomp 287 brake levers where the right lever controled the rear rim brake and the the arai drum with the left lever controling the front brake. All of these combinations work it's just what you are most comfortable with.

bockwho
04-13-06, 09:00 AM
I think tandems ltd offers what you speak of for newer sti shifters. however I like the bar con idea better easier to repair or deal w/o if a malfunction occures. suntour bar cons would be idea also.