act0fgod

I know there are folks that do loaded bike packing on gravel in Colorado and wondering what brakes and rotors people are running to keep speeds manageable without warping rotors repeatedly?

We converted one of our tandems to a gravel bike and it's a bit sketchy on the long descents. Did a 30 mile out and back ride today in Durango that was 15 miles up (3k feet elevation gain) and then back down. The problem was the 15 mile continuous 3k foot descent.

The BR-RS785 calipers with J04C metal pads never gave out but the rotors were badly warped and constant rub of the pads when we got back in town was annoying. Spinning the wheel results in a pretty quick stop due to the pad rubbing the warped rotor. Tried truing them for a bit as we're going to ride in Canyonlands Park tomorrow but not able to completely get rid of the rub. The rotors were new TRP-33 rotors. They were new because last weekend we were riding in CO Springs and did a 10 mile out and back (10 miles up and then 10 miles back down) on gravel and completely warped the Avid disc we were using (they also were squealing terribly so it was at least nice the TRP-33's weren't very loud).

We don't feel comfortable much faster than 25mph (around 45mph is where my wife gets uncomfortable on the road) on these windy gravel roads but that unfortunately happens really quickly with a 4-8% grade so I'm constantly braking hard to get us under 15mph then we quickly get back to 25mph.

I'm thinking about buying shimano saints with ice tech rotors or magura MT7's with MDR-P rotors, but wondering what others are using. Maybe there really isn't anything for this type of tandem riding.

jccaclimber

We ride road and my wife/stoker isn't appreciative of high speeds. For long descents we have an Arai drum. It doesn't produce a huge amount of braking force and you pay a solid weight penalty carrying it around, but it also doesn't overheat.
Look into threads about the disc options used as Arai replacements, or hunt down a used Arai if you are willing to meet the mounting requirements (left side threaded hub and NDS chain stay pac-man or adapter).

Leisesturm

Strap one (or two) of these to your Stoker ...

Rick

I am glad you were not injured. My 1990 Burly Bongo has Magura hydraulic rim brakes and an Araya drum brake. You have disk brakes and the Araya drum brake has been discontinued. I have disk brakes on my custom touring bicycle. I probably weigh as much as a Tandem team. I live up a grade and can coast down hill through the neighborhood at 46 mph if I don't value my life. You need to have the largest diameter rotors that will fit on your Tandem. You also need the thickest rotors you can find. less than 2mm thick is no good. TRP makes 2.3mm ebike rotors, but they were not available when I replaced my rotors. I purchased the Magura ebike rotors. They are 2mm but have less cut outs in them. Yes they weigh more than other rotors of the same thickness. How are you applying your brakes. On a grade when I drove tractor trailer we used stab braking. meaning applying the brakes firmly until you were at a lower speed, then letting off until you are at the higher speed you don't want to go over. Then repeating this as many times as needed. This kept me from loosing my brakes. This also works on Tandem bicycles. People who draft unannounced will not like drafting you when you do this. A few years ago several Tandem teams on holiday were going down a mountain grade with the Avid mechanical disk brake calipers. Parts of the caliper are made out of plastic and there was some melting of the plastic and the brake pads fell out of the caliper. The Shimano Saint has ceramic pistons to help keep from boiling the mineral oil. Sounds like a good option for calipers. I also use the sintered pads.

headasunder

we have ice tech rotors on our gravel/touring tandem they warp on the long descents and rub for a while after I'm a little underwhelmed with there performance and plan to try the magura mdr-p rotor after I get my monies worth out of the ice tech offering.

Rick

I recently put a Magura MDR-P rotor on the front of my touring bike. So far there has been an Improvement. No squalling or poor brake performance. A man on YouTube showed where his ice tech rotor had begun to melt. He was riding a single.

Rick

Some friends of mine had a burley duet and the captain would make fun of what he called the useless Two pounds of garbage on my Bongo. he was referring to what you call a solid weight penalty. He and his wife took a spill one Saturday morning going down a windy canyon. constantly using the brakes going down that grade with light weight rims and the narrowest tires he could find caused what rarely happens. Heat blew the tire off the rim. A few Saturdays later he showed up for a ride and he had the Araya drum brake on his tandem. A Tandem team doesn't have as much wind drag as two separate riders. Because of this they can coast up to a higher speed than a single rider and do it more quickly. You need more powerful heavier brakes on a Tandem. Before the manufacture of the Araya drum brake stopped making them, there was some popular individual with a European sounding name lightening up the Araya drum brake by matching off those heavy cooling fins. I believe he went the way of the dinosaur. After the Araya was gone another individual started producing an Araya replacement. It was boasted as light weight. It did not survive either. Now that the bicycle Industry has successfully pushed the disk brake on us after the third try. We need to be aware of its limitations and act accordingly.

Alcanbrad

I wonder if anyone has, or has investigated using a brake caliper and rotor from the ATV/motor scooter sector. These brakes are beefier and more massive than a bike system and would come with the challenges of adapting the calipers to the fork and frame, the rotor to the hub, and the hydraulics/pull ratio between the brake handles, however all issues should solvable and you would have a setup better suited for purpose.

I have also pondered a system that when you applied the brakes, in addition to the friction, you would also couple the rotation of the rotor to drive a very high speed blower that would attempt to cool the system. The cooling would be secondary, the air resistance through the blower would provide much of the breaking force (think of the classic wind trainer). Such a system would be noisy, need a robust coupling and gearing set up and would be less effective at slower speeds but should do the job.

Given the proportionally small number of tandems and an even smaller number of tandems needing such a solution, the economics are not there to justify doing either commercially. It would be a one off scenario.

Rick

I believe Rad Powers commercial tricycle has motorcycle type disk brakes.

jccaclimber

Araya is a company who makes rims.
Arai was a company that made drum brakes. It does carry a weight penalty, but obviously I still carry it.

The previous owner of our tandem did loaded touring across the Rockies at least once, through the Alps a few times, and from my understanding never overheated the drum despite doing the descents slowly with the drum dragging the entire way down. I’d bet it has the original pads, and they aren’t particularly worn.

Note though, I have the benefit of rim brakes. If my frame didn’t have posts for V or canti brakes, or allowing me to run the drum as a third brake, I’m not sure how I’d feel about it. I did just that for a while on our previous tandem (front V brake + rear drum, no rear rim brake), but it is nicer having all three.

Rick

ARAI DRUM BRAKE

act0fgod

We previously had a burley with the Arai drum/drag. I am considering buying a new rear wheel/hub that is threaded and going with the front disc and then rim brake and drum on the rear. Problem is the rear brake bridge isn't really a brake bridge but has a vertical hole for fenders. Also will be limited to hydraulic (which helps as there is no cable routing for a rim brake either).

We were joking about the parachute option yesterday.

Rick

Is your Tandem made out of steel. Who makes it and is it road or mountain? Some pictures would be helpful.
I have a touring bike made out of steel and Co-Motion will put Cantilever mounts on it. Obviously for a price.

longpete

The wider the tire the more brake power it has. Magura MT7 with depending where we ride 180,20.3 or 22 cm disks.Not only the diamteer plays a role, also the weight of the disks.
Magura MDR C weighs about the same ass the real old magura disks and has the same 2mm diameter. 10 gram per cm diameter gives a reliable disk. Our system weight is from 180 up to 200kg.
Braking continuously however will kill every disk brake. Brake hard and roll again, if that's not possible 600 negative altitude meters are still ok. But not on technical singletrack which descends 10% or more.
Only one solution, stop and let the brakes cool down.A bit of water can help, but red disks don't like cold water.
You can use your bodies(spread knees+arms, sit up etc) and jackets for extra air resistance.
On the road with a much lighter tandem and up to 600 altitude meters in a row vbrakes do their job also, but there's always the danger of an inner tube or tyre melting.
I melted shimano ice tech disks, bent avid disks, shimano discs and magura storm discs. But never an MDR or old Magura disk.
Magura MDR p 6 I not tried yet.
What also helps is a larger diameter fork.
I like to use a bigger disk on the rear wheel and metallic pads, on the front wheel organic pads.

Rick

You can easily warp disks and boil the brake fluid on a Tandem bicycle. You can't easily cause the tire of a rim braked Tandem to blow off of the rim. I have only heard of and seen this happen on narrow tired Tandems using poor brake management. I have a 1990 Tandem with rim brakes and a drum used for a drag. I have never used less than a 1.5" wide tire on it. I pulled a custom trailer with three children in it. We picnicked up a canyon several times and coming back I used the drag brake to keep the speed from becoming excessive. I replaced the original self activating cantilevers with Magura hydraulic rim brakes. Once setup no adjusting is necessary. I just put a 180mm Magura MDR-C Disc Brake Rotor on the front of my touring bike. The TRP ebike rotors that are 2.3mm thick were not available. The Magura disk solved the squalling problem. With proper braking meaning stab braking after the third slow down the previous front disk became noisy enough to cause me ear pain. I believe the ebike rotors are as close to Tandem rated as we are going to get.

act0fgod

Steel Bilenky made for the road/touring.
The 90 degree corner brace is something I put on for attaching the rack we sometimes use.



It's a bit dusty after some four wheeler "roads" yesterday in Canyonlands. Brakes weren't a problem as there weren't any long descents. The powdered sugar like sand that buried our tires is what beat us up (along with the 117 degree temp reading on the garmin at 10am).

Rick

[QUOTE][Bilenky made for the road/touring/QUOTE]

If it were mine I would send it in to Bilenky and have the cantilever mounts put on the frame. I am going to send my Burley in for paint and some hydraulic cable guides. I have the discontinued hs66 brakes and will be switching to the Crazy bar like I put on my touring bike. Magura still makes the hs33 hydraulic rim brakes. They are for MTB type handlebars. Once setup they are easily maintained and stay in adjustment. No tools are required to change the pads. There is no toeing of the brake pads required. If you are using drop bars there are high quality cantilevers available. I don't like linear pull brakes. Paul makes a couple of models'. Rodriguez makes the Big Squeeze, Avid also makes easy to adjust cantilevers.