stever

hi all
anyone out there in cycle forum land with knowledge of disc brakes for tandems....

currently i have magura hydraulic brakes which are good
but i am worried re rim wear due to excessive force on the rims

which are sun rhynos

i believe some tandem specific discs may have been appearring
on mtb tandems....i wonder if any manufacturers
are producing any for touring tandems

any info would be great also is it a viable option or is it
very expensive ????
steve

Geronimo

I think Magura is the only manufacturer who is claiming tandem-capable disk brakes. The Gustav M DH brakes are the ones they advertise as being tandem friendly. I would imagine a set of Hayes with 8" rotors would stop you pretty well but they won't endorse it as such. Good Luck

https://www.magura.de/english/frameset/default.htm

stever

re discs
i was perusing the web the other day
and noticed that orbit bikes have a tandem specced with
disc brakes well one on the back
they are from rst ???
tried there site but was in taiwanese
the search continues

riderx

I would think that any heavy duty Downhill MTB disc brake would be up to the tasks of Tandem braking. I'd start the search with Hayes since they are somewhat of a standard.

MichaelW

front or rear brake?

stever

rear brake

stever

re tandem specific discs brakes i found this faq

hope it helps plenty of good reading

https://tandem-fahren.de/Mitglieder/C...m/DiskFAQ.html

TandemGeek

Chris Timm has published an extensive report on tandems and disc brakes on his Web site that is well worth your time to read through:


Here's my take on what's out there today. For road-only/specific use, there is only one disc system: The 203mm Santana/Formula hydraulic brake system is the only one that's seen full-time duty as a rear brake for tandems. Initial reports were mixed but it seems as folks have learned how to adjust them performance has been more predicatable and reliable. However, if you fit your tandem with a full-time rear disc recognize that you've lost the ability to use it as a drag-brake.

For off-road purposes, there are now 3 tandem rated hydraulic disc brake systems and two mechanical systems that are or are nearly approved for use:

Hope's Enduro Brakes (previously known as O4DH) which are an open system featuring a four-pot caliper design. They offer up to a 203mm rotor for the front brake application and 185mm for the rear, although 145 or 160mm rear spacing can get to be problematic with regard to clearance. We've been running a pair of these on our Ventana for 2 years and have no complaints.

Magura, in addition to its open/4 pot Gustav M downhill disc brake system is now offering a tandem-rated version of the Julie hydraulic disc brake.

Avid's newer mechanical disc brake system has just been adopted as the disc brake standard for daVinci's off-road hardtail and full suspension bikes. Avid cautions users to keep fresh pads on the brakes and to be attentive to modulating front to back on long descents to guard against excess heat build up -- which could lead to warping of the rotors.

Haye's mechanical systems look to be every bit as good as the Avid system, but Hayes will not give the OK for tandem use. They are STILL testing. Glenn Erickson will be adapting the Hayes -- without their full support -- to his road tandems as a secondary/drag brake. His previous tandems used an older, no longer produced Hope mechanical disc caliper system that worked well as a drag brake but could not be relied on as the sole brake on the bike -- yes, we have one of these.

TandemGeek

Oops. Forgot Chris' URL for this Disc Brake FAQ's but I now see that it was already passed along.

Regarding cost, hydraulic disc systems are expensive, even if you already have IS mounting brackets on your fork and rear triangle. By expensive, the disc brake systems are between $185 - $285 per axle + you'll need new disc compatible hubs which will run you ~$120 and up front the front hub and ~$250 and up for the rear.

The mechanical systems are much less expensive since they don't require specialized brake levers or hydraulic brake fluid lines. But, you'll still need new hubs.

Bottom Line: For road tandems, the Arai drum brake is still the best value for a bomb-proof, reliable auxilliary or rear drag brake. They aren't as sexy looking as the discs (although the shaved models are pretty cool), but they are certainly affordable ($120) and proven to be effective.

bugatti2me

I'm an old tandem dog so I can only tell you about what has worked for me. Since the early 1980's I have been running Phil Wood encased discs front and rear plus cantilevers. Each is set up on twin cabled levers. It is great on long, step descents as I can alternate between the disks and rim brakes. It does require a lot of hand pressure (not great from the tops of the hoods). It is also fussy to balance front and rear when setting up. It was quite popular back then.
We were a heavy team (about 400lbs plus a light bike) riding in fairly hilly Hudson River country north of New York. We once started a weekend of riding with all 4 brakes. On Saturday a cantilver shoe popped out on a down hill and we couldn't find it (no spare, so down to 3). On Sunday the cable ball end popped out of another brake cable (down to 2). Made it home OK with one disk and one cantilever but sometimes missed our redundent system. It gave us a great sense of confidence as we are agressive downhillers. Our personal, computer measured downhill speed is 54 miles and hour. We would have liked that single extra MPH to brake the speed limit.

Our only other problem with the Phil disks, was a time when we only had one Phil disk on the front at the start of a small down hill, I squeezed the brake to slow and sudenly found the bike shooting forward rapidly rather than stopping. The composite disk stripped off the hub spline. When I contacted Phil, apparently this had happened a few time becuase he had recently reengineered the brakes with heavier (thicker) disks. This required remachining the interior space for the disks at no cost to us (including shipping). No problems in the 15 or so years since.
I have a single commuter bike with "V" brakes and have like them. We recently got a second used tandem (Santana MTB with road wheels and only "V" brakes) and I'm impresed with their stopping power but have not yet tried them on long descents. The pads seem to wear faster than the cantis
I'm intrigued by the new brake technology (hydraulic, external disks, "v" ) but keep finding people/builders that point out the problems (Santana, R+E) with them. I don't know if there is a better way to stop or slow down our fast, heavy two wheel trucks on steep descents with less than three brakes.

PaMTBRider

If you check out the new Cannondale road tandems they are being shipped with Avid mechanical disc brakes front and rear. This doesn't mean that Avid approves these brakes for tandem use but Cannondale is taking a lot of liability if they are less than adequate.

TandemGeek

I'm surprised you've been able to keep the Phil Wood mech. disc in service. Almost all of the original discs suffered similar failures as did yours and Phil stopped producing parts for the discs in the early 80's after a couple of lawsuits were filed by teams who had catastrophic failures, one allegedly resulting in a permanent disability. The units that Phil fixed -- again, like yours -- seemed to have held up quite well.

This can be a sticky area since Bill is quick to find fault with other discs that can't pass his torture tests but, at the same time, fails to acknowledge that his own disc offering -- the Formula hybrid hydro/mech -- while somehow passing his tests has routinely failed on a great many of his tandems. In fact, the current trend for many Formula disc owners who have had problems -- and there are a lot of them -- is to remove the Formula and replace it with the Avid disc with which he seems to find so much fault. Go figure. Interestingly enough, of the many, many, many tandem teams who have decided to dismiss Bill's cautions and use the Avids, as well as Co-Motion, Cannondale, Burley, and several custom builders who sell and install them, there have been no widely reported total disc failures that I'm aware of. I've searched them out and the best I've been able to find is incidents where the discs were superheated to the point where the red plastic (and replaceable) adjusting knobs for the pads softened enough to become deformed or come off the brake caliper as well as a few heat stained rotors. But, in all of these reports the brakes did not actually fail, continued to work, and brought the tandems to safe stops. It can easily be assumed that any descents that "cooked" an Avid would have had a high probabilty of causing a tire blow-off on any rim brake equipped tandem that didn't have a supplemental Arai drum brake, which remains the default brake device for the most extreme downhill descent speed control device requirements.

As for Rodriguez, we actually had a thread a while back which referenced some information that R&E posted to its web site: https://www.bikeforums.net/showthread...279#post556279

I sent an Email to R&E to ascertain if the information on their web site that is critical of discs is up to date and representative of their current assessment of the products but never heard back. Have you had recent discussions with Dan or someone else at R&E on this topic or is it the comments on their web page to which you are referring? If it's still the Web page, I'll have to ask their frame builder -- the gentleman (also a pretty good friend) who makes the frames that R&E puts its name on -- what their current position is on the current disc brake offerings since he also builds tandems under his own brand name and for another major builder on which rear-only and dual Avid discs are offered as an option.

Again, disc brakes aren't for everyone but, for certain teams and riding conditions they are performing quite well, ourselves included as a few months ago. Also, not that it means anything, I recently corresponded with Cannondale regarding customer feedback now that they have two years of OEM dual disc brake production and sales under their belts and they gave me the corporate line: No problems reported to them or Avid, although Avid has had to help bring some of the dealers up to speed on the proper set-up and use of their discs.

TandemGeek

Avid does, in fact, approve the 203mm version of it's discs for use as primary brakes on tandems, but does not approve their use as a drag brake. There was an attempt to curtail Cannondales use of the Avid disc brakes during Interbike two years ago which prompted them to do some additional testing before releasing the OEM dual disc brakes in the US. Interestingly enough, Cannondale already had a lot of experience with disc brake testing from its failed attempt to introduce the MT4000 In 2000 with dual Magura Gustav M's and their Moto FR-T fork; the lawyers apparently weren't satisfied with the margins either on the fork or the brakes (not positive which it was) and the dual discs were subsequently not offered as an OEM option here in the US. It is noteworthy that there are some early Moto FR-T forks in circulation with disc brake tabs that are NOT approved for use on tandem applications as well as a second generation model that was released with beefed up fork legs and disc tabs that is.

All that's water under the bridge now. However, with Avid's support, Cannondale has offered it configuration of dual primary disc brakes for two years now. Moreover, a rear-only primary disc brake is offered as an option by Co-Motion and Burley, both of whom use the 203mm rotor installation. Co-Motion goes so far as to run on one set of braze-ons for the rear brakes and will not sell you a tandem with both rear rim and the disc brake installed from the factory to preclude a factory installed disc drag brake configuration and I believe Burley is doing something similar. Much of the early research by Avid on the tandem-worthiness and durabilty of its mechanical discs was conducted by the "Wrecking Crew" at daVinci tandems who are located just down the street from Avid in Colorado. Todd Shusterman and his off-road team (the aforementioned Wrecking Crew) put the Avids through their paces on off-road racing circuits as well as the mountains in Colorado and Europe on personal tandems before offering them to customers.

Does any of this mean that an Avid brake has never failed or never will fail? Absolutely not. But, as someone who frequents the major tandem discussion boards, who also stays in touch with a number of the builders, and who has been using and discussing disc brakes on tandems since 1998, I am certainly keeping my ear to the ground for any reported problems. Again, all I've heard of so far are high-heat induced melted plastic adjustment knobs and discolored rotors. If y'all have first or even reliable second hand reports of failures I'd love to hear about them. Crappy set-up and resulting performance? That's another problem that has more to do with a lack of experience on the part of the set-ups as well as some really funky early attempts at integrating the MTB / BB7 version with Ergo levers.

K&M

Our road tandem (Burley) uses the Avid disc for its rear brake and we have dished out some pretty serious punishment to it, often taking it down long, steep and technical descents where heavy and frequent braking is a necessity. It has produced a variety of unsettling noises and vibrations at times -- but it has never failed to safely slow us down. On one occassion when bad pavement caused us to lose our nerve completely and abuse the disc by using it, essentially, as a drag brake, we still were unable to melt the knobs or warp the disc. We would definitely recommend the Avid, although we would urge anyone using one to add a travel agent (if it doesn't come installed with one) as this improves the performance considerably.

zonatandem

Any kind of braking system can, and, probably has failed. But if we all worried ourselves sick about this possibility, we'd never get out of bed in the mornin'!
Some folks have developed a 9/11 mentality . . . what if????
Select the system that seems prudent for your team/usage.
Life's too short . . . Let's go out and ride!

phinney

No travel agent on the Cannondale's and I don't see how a Travel Agent would be any benefit. There isn't enough lever travel to add more leverage but there is enough lever travel so no more is needed. Maybe the Burley uses the off-road Avid caliper?

TandemGeek

Yeah, I'm kinda struggling with this one too...

If Team Godzilla, aka. Kip C. or perhaps Tim P. is reading please chime in, but to the best of my knowledge none of the Avid's that our friends are using on their road tandems-- to include a new as of July 4th Weekend Burley Rivazza -- has needed any brake boosters.

The only thing that I can think of is that some dealers are finding it easier to set up the brakes and to eliminate any initial rotor drag** by leaving more room between the pads and rotors than intended and using the cable booster to pick-up the slack. This would certainly work and probably provide quicker brake actuation with less lever travel. I guess if you don't mind introducing another moving part into the brake cable system and the associated aesthetics of the devices, there aren't too many downsides to the use of a booster.

My approach to addressing the nuances of Avid disc installations on the rear wheel of a tandem remains the use of a supplemental return spring between the caliper's cable stop and torque arm. Instead of increasing the total amount of travel used to actuate the torque arm and caliper's pistons, the supplemental return spring helps the built-in spring tension adjuster by compensating for the added drag that comes from a tandem's long rear brake cable run. This method of pre-loading the torque arm simply aids in piston retraction by relieving some of the cable drag that pulls against the torque arm as well as providing a slight improvement in lever feel.

Ultimately, it's whatever works best for you and your tandem dealer / mechanic and if the addition of a travel agent makes your tandem's rear disc brake feel better that's all that matters. I'll have to keep my eye open for someone who is riding a C'dale or Burley set-up by Mel at the Southern Tandem Rally in October to see how the TA has been integrated into the system.

** Rotor Drag is a slight rubbing that sometimes occurs between the disc rotor and brake pads. It is not uncommon with a new disc that hasn't been used to see that it is not perfectly true. However, the discs will normally straightened themselves out during the initial break-in process.

mtbcyclist

I have been using 6" avid mechanicals on my mtb bike in terrible conditions such as rain/hail (not by choice) on a steep downhill in the mountians of North Carolina and have had NO issues. They rocked. I love the 8" avid on my Burley and it has been great for the 2 months I have had the bike. Have not had it up in the mountians yet but that day will come and have no doubt the avid will do the tric.

TandemGeek

We "busted the cherry" (can I say that?) on our rear-only Avid descending 15 miles or so through the Pisgah National Forest on Highway 276 from the Blue Ridge Parkway to Brevard through the Pisgah National Forest on a rain-soaked winding mountain road with the temperatures hovering around 50 degrees.

Although not quite broken-in after a couple shake-down rides at home, the Avid's performance was incredible... offering precise modulation, exceptional feedback, and enough pure stopping power to all but eliminate the need for using the front brake on 6% - 9% grades as we set-up for the entry to each turn. Once the novelty of having a rear brake at my disposal that "felt" like our Campy Chorus caliper brakes but with 10x the stopping power wore off -- noting that Debbie noticed the same improvements in stopping power and gained immediately confidence in the Avid's performance on the rain-soaked descent -- its use was returned to the normal duties as far as the front-to-back brake bias that I would normally employ on most descents, but with the knowledge that there was tons of stopping power in reserve.

In fact, the only concern I would have for a person using the Avid rear disc for the first time on wet roads would be if they had a bad habit of braking through turns (vs. before entering turns) and unintentionally skidded the rear wheel. Of course, the Avids have so much stopping power that a fat fist on the brake lever could also induce a rear wheel skid on dry pavement, underscoring the importance of getting a feel for how a brake like the the Avid works on familiar terrain before tackling challenging braking situations.

LV2TNDM

Here's a thought (and a challenge for Ricardo): double discs on the front? Motorcycles use 'em, why not a similar set up on mtn. (or road) tandems? Seems like an ideal solution to overheating problems - twice the heat sink & friction. But I guess the need for a custom fork & hub and the added weight plus limited market would keep companies from jumping at the chance.
Ricardo, any room for a third brake lever? Ha, ha, ha!

TandemGeek

It's already been done... but never moved beyond functional prototype. Therapy Components and Intense Cycles teamed up back in 1999 and brought two one-off Intense full suspension tandems to Interbike, one of which had dual hydraulic discs up front.

mtbcyclist

Oh my god!!!! As a tandem road rider and a non tandem mountian biker I think I have found the tandem moutian bike I must have. That thing rocks!!!

You from NC. Tandem Geek? I am from Raleigh NC.

TandemGeek

Nope, but we do so enjoy riding there... We do Tsali a couple times a year with the off-road tandem, to include what has started to become an off-road rally in the fall hosted by David Lee from Asheville. We also have started to spend our Memorial Day weekends in Brevard and will be visiting friends in Taylorsville over Labor Day. We regularly ride with tandem folks from the Raleigh Area (Smith & Claude, Mark & Betsy), Charlotte (John T. & Susanna, Dan & Dolores), as well as Team Godzilla (Kip & Anne). Well, not so much ride with them as try to hang on their rear wheels as long as we can or as long as they're nice enough to let us.

ricardo kuhn

man i don't even think that is that challenging, sure is not easy but is just question of machining a hub able to take the other rotor a fork mount for the caliper and a addaptor for the pod,,what i'm trying to say is that they are only a "maching" operation,,you measure, you program, to have the parts need it ten minutes later...

actually Marchocci use to have dual disc mounts on their earlier forks,,remenber the brake technology was pretty lame then, but with the current equipement is just no need for that...

in fact many aftermarket companies that make motorcycle brakes are trying to get away by ussing a Single rotor as oppose to two,,

let me show you a example
My KTM 950 is one of the most cutting adge "ADVenture" bikes in existance but still have some short comings one of them the execive(not really necesary) mass on the front wheel that makes the steering kind of slow and also tend to overheat the fork and the fliud do to the "execive" Inercia


anyway i really great way to drop some pounds "statically" is to take one of the rotors and install a better quality rotor (lighter aluminum carrior, floating rotor, more gripier metal)and caliper(FOUR Piston caliper affix to the fork as oopose to the stock caliper that "Floats" on rails and only have TWO pods) to assume the dutty of the dual rotor set up

Let me tell you the diference is night and day in every respect (Remenber this is for the dirt, so you don't need HyPeR Powerful brakes,,since the knobby tyres can not really take it) the bike handles a lot better, you can run the compression and preload on the forks 2 /3 clicks lower, hell you can even run a less dense fluid on the forks that makes them more alive and reactive,,all this because you lost Seven pound of static mass and i have No idea how many of rotational mass



Sorry about the Segway but i think was a good way to explain the diferences it makes even on a bike as expensive and evolve as the 950 (pretty much the same the run at the dakar


actually to me the real challenge will be to have some kind of "porcentage" brake sistem, when each of the brake levers actuate part of the front and part of the rear brakes or even better imagine and brake on the stokers bars (I don't think i will like that,,since ussually they are super scare and we will not go anywere) that is "SEmi" connected to the brake sistem, as simple as two hoses connected to the same caliper or as complicated as a "Master distribution box" were all the brakes connect and the force gets distribute in the best possible way according to road conddicions, speed, etc...
Upss i think somebody press the "Geeky ricky botton" on my head

anyway I love the fact that a tandem can take as much braking as you can produce, since if I install super powerful brakes on a half bike i be flying over the bars in no time...

Oh did i tell you guys that the other day I did my first "stoppie" (Lifting the rear wheel of the ground when you are under heavy braking) with a 130 pound stocker,,, man that was fun and for sure I'm glad install the king steelset headset, the 20Mm axle and the FUNN fork because I'm sure a more convencional fork will bend in half, well that is it the QR release did not fail before.

pictures to come I promise

sorry for the long and a little offtopic segway...

basically the best setup is the Biggest and lighest rotor that you can get (205MM on a bicycle so far) and the most power caliper you can get

ricardo kuhn

Oh Yeah I remenber that Monster, pedaling that bike was like trying to walk on a water bed,, i think you guys get the picture, for sure really impresive and substancial in every way, i got to test ride the demo bike at Interbike..

also the legend around here is that some "Guppy" A.K.A. Rick guy with a bunch of toys,fancy shoes and a trophy wife have one of the Intense tandem in walnut creek dannville and somewere around the bay area..

I will love to see one again..

my self I still WaNt one of the Nicolai's with the G-boxx in the middle of the frame

but i'm just not willing to sell my motorcycle to be able to buy this frame..