bwebel

Pretty much any brake, aside from a drum brake, will fail in this situation.

Leisesturm

I'm still pretty certain that about the only way the OEM brakes might fall short is in the hills. Arai drums are discontinued but they were/are popular. They are always showing up used or as OEM on secondhand tandems. If I was the o.p. I would pursue no other line of modification but the acquisition (somehow) of a drag brake to supplement the OEM rim brakes. While looking for a used Arai drum I came across this: https://www.sjscycles.co.uk/brakes/k...-arai/?geoc=US. Seller is first rate. Finding a hub with left hand threads is pretty easy. Fork swaps, frame modifications ... that way lies madness. FWIW.

runwld2

We had a 80's vintage Motobecane tandem (interclub) towing our 20 month old daughter in a loaded trailer, front and rear racks (clothes, camping gear) ( I figure we were about 440 pounds total) over the Green Mts. of Vermont. The Arai drum brake performed perfectly. It was controlled by a downtube friction shifter, so it could be set on . Recommend it highly.....which someone would bring it back.

Chilepines

Just piling on the experiences we've crossed the Green Mountains with a trailer weighing at least 40 lbs and we are a 350 lb team plus the bike, with rim brakes, with mechanical discs (BB7) and then with Magura hydraulics. Had 203 rotors which I then downsized to 180 with the hydraulics and still did fine. We do ride pretty fast down those roads and I'm always careful to pump the brakes letting off whenever I can.

mtseymour

The TRP Spyre and Hy/Rd both use cables from the levers to the calipers. The only difference is that the Hy/Rd use a hydraulic caliper for more power and automatic centering. Where is the "increased complexity" in using the Hy/Rd with S&S couplers?

CaliTexan

Don’t recall the details, but could have been referring to some part of assembly / disassembly process, or maybe the adjustment, or maybe the need to remove the calipers (slightly larger/different shape) to get into the cases? Point is that I was told the performance improvement was not large, and as it turns out, we’ve been happy with the Spykes.

mkane

Probably already been said. Any brake will and can fail if overused.

daywood 

We have what I like to call Active Brake Management on our tandem. Once we're at around 25 MPH, there's an audible warning. Beyond that the Fingernail Brake Actuators are deployed. Thus I never have to worry about bringing it down from great speed. I also tend to alternate between the rear and front brakes on long descents (assuming we're not on gravel), and I tend to brake in intermittent hard short bursts to keep from riding either brake and overheating them or the rims. I think that learning to drive a car in the era of drum brakes taught me lessons I can carry forward about the perils of riding the brakes (any brakes) on long hills.

mtseymour

You're using a safe and effective braking technique. We used to own an Arai drum brake but were glad to switch to better caliper and then disc brakes.

SJX426 

Our 94ish Burley Duet has the Arai. I happened to find one at a coop that was in the box with brake calipers for $5 several years ago. I now have spare parts.
P1010224 on Flickr

The difference from the Karasawa is significant IMHO. The Arai drum is a casting, not sheet metal and has extended cooling surface area around the shoe assembly instead of being encapsulated by it. I think the cooling is far more effective with Arai.

grumpus

There's not really any need to modify a front recessed caliper, as it's already a rear nutted caliper - just drill the recessed nut so it slides on the mounting bolt, and fasten it with a stainless M6x1 nut.

Groasters

I agree with the above posts that suggest that getting a rear wheel with a screw-on hub brake is the best option for drag braking on descents. Top choice would be finding a used or NOS Arai drum (illustrated above), second choice a new Japanese version, the Karasawa, from SJS cycles as mentioned. I know someone who retrofitted an Arai to a frame without the braze-on for the stay arm of the drum but he used an after market clip that worked fine. Torque levels on the chainstay with an Arai are not in the order of magnitude of a disc brake.

I agree that the quality of the Karasawa looks well below the Arai, but I've never seen one for real nor used one.

Check rear dropout spacing on your bike is compatible with the hub.

mikemelbrooks

I am looking after and piloting a latish model Cannondale tandem I have upgraded the front brake from 200 to a 220mm Hope disc. There isn't enough space for a 220 mm disc on the back. The rear wheel is fitted with a V brake that the stocker controls it doubles up as a parking brake. I still overheated the rear disc during a recent century ride when we were over taken at the top of a hill and the car dragged it's brakes on the way down. The calipers are Avid bb7s. In the summer on familiar dry open roads it's not a problem. But riding hilly B roads where there are wet leaves, mud and horses to watch out for I still feel the braking could be improved. I have a "radiator disc" ordered which I hope will keep the rear brake cool.