candrus 

I'd like to set up an Arai drum brake with the control next to the captain handlebars using a thumb shifter. Is there any advantage of using a ratcheting thumb shifter over a simple friction shifter?

IPassGas

The stoker controls our Arai and she prefers a regular brake lever to the thumb shifter. We used a thumb shifter for awhile, but it did not hold well and her thumb would tire on long descents.

Philly Tandem

Since the Arai usually acts as a drag brake for long descents, using a ratcheting shifter allows you to set the brake at a certain level and easily maintain that during the descent. You can do that with a friction shifter, too, but the shifter screw tension has to be set pretty high to keep it from slipping. If you have the choice, go with a ratcheting shifter IMO. I've used Arai brakes on both our tandem and triplet for loaded touring in the Alps, and the ratchet feature was very nice to have. I also have it set up for the captain to use.

Artmo 

+1 for ratchet

candrus 

Thanks for your input. I suspected that the ratchet option might be a better system than friction. Decades ago I had a Santana with a drum brake but it was tied in with the front brake lever and didn't seem to address the problem of what happens when the cantilever brake gets too hot. One time on a long steep descent with brakes squeezed as hard as I could, the front pads imploded leaving only the drag brake and some smoking rear pads. I couldn't stop but we did get to the bottom of the hill at a controlled speed. Ever since, I've not pushed the limits of a tandem without disc brakes or a drag brake. I'll be installing this Arai drum brake on a vintage tandem that we recently acquired. We can then move on from cautious riding to some faster riding.

Alcanbrad

Ditto on the ratchet. We started with a friction shifter and it would not hold position unless it was tensioned so tight it was almost impossible to move and set. Mel at Tandems East sold up a ratcheting bar end shifter and happy days.

JanMM

Have never had an Arai brake but sure was a fan of SunTour ratcheting downtube and thumb shifters.

candrus 

Will the clamp on a vintage Suntour XC Thumb Shifter (Power Ratchet) fit on a road bar? The only other ratchet thumb shifters I can find are Interloc Racing Design Power Ratchet, which are kind of expensive. Yet, IRD claims that their shifters fit both mountain and road bars. Any other options out there?

unikid

Maybe something like this? https://www.randombikeparts.com/prod...ecbcb70c&_ss=r

tandem rider

I used a barcon (bar end) Shimano indexed shifter for an Arai drum brake. A ratcheting or indexed shifter can be set for long descents and as a parking brake on slopes. The locked brake might also keep someone from rolling the bike off.