[CR]re: tandem brake info...

(Example: Framebuilders:Cecil Behringer)

Date: Sun, 20 Apr 2008 15:41:19 -0400
From: "Harvey Sachs" <hmsachs@verizon.net>
To: Rnitro1969@aol.com, Classic Rendezvous <classicrendezvous@bikelist.org>
Subject: [CR]re: tandem brake info...

Robbie Fellows asks:

and need some ideas on side pull or center pull brakes that work on tandems ++++++++++++++++++++++++++++++ I was very active in the Tandem Club of America back then, and there are few topics that evoked similar passion and differences of opinion. Here are a few observations:

1) Many or most of us feel - to this day - that a tandem should have a rear hub brake in addition to its two caliper brakes, for effective speed control and redundancy. At least for riding where there are substantial steep drops that may require sustained braking. The weight of two riders + junk and bike can mean that there is more heat to be dissipated than one can safely dump into rims.

2) Weren't many classic hub brake options available. Principal one was the "Atom" drum brake, derived from some sort of motorized bike component, and typically with (a) French thread FW, (b) 36 oversized spoke holes, and (c) weak axles that bent. I still have one of these... Another option was the Phil hub, a beautifully machined device that didn't work well. They were built like a motorcycle clutch. The early ones used a fibre brake disk with a spline center that stripped out, but only when in use. The later ones used a metal spline set with disk material attached to it; I have one of these in crisped (burned) form. But, a lovely design. A third option, pioneered by Bill Boston, was an early Shimano disk brake, typically the "E" version. Like the Phil, its disk mounts on a standard double-sided hub. I have rigged these on hubs as narrow as 130 OLN, but it is not easy, and the brake is a bit fidgety. It took us a drop of almost a thousand feet to scorch and warp one of these rotors, but it degraded nicely. I think that "first flight cycles" still has a bunch of these, and I consider it the least inappropriate option, if you can rig it. Late in the era (after the first Santanas), the Arai came out, and is probably the easiest to use and install. Of course, if your particular fetish is early British tandems, I used to have a BSA 3-speed drum hub, with cog for 1" skip-tooth chain. Sturmey made these, too. I strongly recommend against any coaster hub, since they just don't have the surface area to dissipate heat.

3) Till late in the era, the norm for rim brakes was the Mafac Tandem canti-lever. Oversized arms and longer pads. On the other hand, we happily used Universal 61 CPs on our Town & Country, for thousands of miles (with Matthauser pads toward the end). I prefer CPs to side pulls for tandems, because they have greater leverage (with the same levers). But, lots of folks used Campy sidepulls on road tandems.

4) One big difference on a tandem: rear brakes can actually help slow you down. It's not just that there is a rear rider, but the much longer wheelbase means that it's much harder to transfer all the load to the front and lock up. So, front brakes matter, too.

5) I am very suspicious of front hub brakes. a dished front wheel can collapse easily in some low-speed maneuvers. Seen it happen.

6) If I planned to ride a vintage tandem a lot, I'd probably rig a modern rear wheel with decent (large diameter) disk brake for my general riding, but keep a vintage wheel for special occasions.

Your mileage may vary.

Harvey Sachs
mcLean va. usa.