[Yak] tandem brakes

[John S. Allen]

At 09:27 PM 9/11/2008, Harvey Sachs wrote:

Good advice, Harvey. A few more pointers:

>Rim brakes alone can overheat with tandem loads, and some folks 
>claim to have blown tires on mountain grades as a result. Thus, two 
>calipers on the same rim is not advised.  We have gotten a 70s disk 
>hot enough to (a) warp a bit and (b) scorch the paper label pretty 
>completely. I've seen a Phil Wood disk (discontinued quite a while 
>ago) that was rather charred.

This is real, not only a claim. Sheldon Brown and his wife blew a 
tire with only 400 feet of descent, on a big-wheel tandem. Inner-tube 
patch cement can melt, too. David Gordon Wilson had both his tires go 
flat on a mountain descent on a solo bike. The problem is worse with 
the smaller heat-dissipating area of small wheels. Wider rims 
alleviate that problem somewhat.

>We set up our tandems with the left hand working the front rim 
>brake, and the right hand getting the rear rim when in the normal 
>riding position. Our tandems have always had drops, and the rear hub 
>brake is controlled by a third lever, on the lower drop. Ergo, can't 
>use both rear brakes at once; can't reach them.

And I operate my drum brake with an old friction-type shift lever 
(bar-end shifter or thumbshifter) -- which lets me set the brake for 
drag on a long descent, or as a parking brake.

Another option which is convenient, but not highly advisable: giving 
control of this brake to the stoker. If the captain decides to sprint 
across an intersection ahead of a gap in traffic, while the stoker 
decides to stop...

John S. Allen

Regional Director for New York and New England, League of American Bicyclists
League Cycling Instructor #77-C and Member of the League's Education Committee

http://bikexprt.com