Tandems at NAHBS, including new Ritchey Beakaway tandem
 

Photos are starting to appear from the 2012 North American Handmade Bicycle Show. Almost all the bikes on display are fascinating to look at, with interesting custom details and impressive workmanship - far more interesting than all of the stock builds at Eurobike and Interbike IMO.

For tandem enthusiasts, probably the most interesting thing is that Ritchey are going to start producing a tandem version of their Breakaway frame. They have been making multiple versions of single-bikes (mountain, road, and cross) for several years using a system that allows the frame to split into two that is far lighter and more sleek than S&S couplers, see their website here (although that suggests that they are now only offering the cyclocross version). At NAHBS, they were showing a tandem that uses a similar system, as shown here on the massive Bikeradar gallery of NAHBS photos (plus the two subsequent photos show it in more detail).

Paketa were also showing off a couple of tandems, see the photos starting here. These include a race model equipped with a Gates timing belt and Ultegra Di2 transmission that weighs about 10.5 kg, plus a time trial tandem with rare Sweet Wings tandem cranks.

I am interested in what others think about the Ritchey tandem frame.

Break Away Design work on tandem?

The dual tubes between stoker seat cluster and front BB?

Wayne

Tom Ritchey built two tandems using his Breakaway coupling design back around 2003. I did a little write-up on the Breakaway tandems after a photoshoot with Tom & his wife Martha Ann surfaced last year:

http://tandemgeek.wordpress.com/2011...rn-to-be-sure/

You can also catch a few more photos and comments of their tandem outings at Tom's blog here where you'll once again see the original Red/White/Blue 700c Breakaway tandem about 1/2 way down the blog.

The 29er with the pair of "Up-Tube" stay-diameter tubes that was at NAHBS looks pretty cool and probably works just fine; he used the same configuration on his 2003 700c Breakaway tandems.

Speaking of new coupling systems, Santana's new couplers should also be hitting the market this year. It will be interesting to see the pricing and to see if anyone else decides to adopt the patented design.

We attended NAHBS yesterday, and I took some pics, which can be seen here.

I've looked through Flickr uploads labeled NAHBS, and where there are tandems, I've put them into a Gallery here and here.

If anyone goes to NAHBS, please let Ritchey know that it would be really cool to see a coupled tandem design that allowed configuration either as a tandem or as a single, by mating the captain's top tube and down tube with the stoker's rear end (seat tube, BB, seat and chain stays).

If the tandem was approximately the same size front and rear, it seems like Ritchey's coupler design could support this, with some mods like a dummy down tube on the stoker's BB. I think this would be the ultimate travel bike, since it could support either single or tandem use.

Thanks for the photos, Ritterview. The Eriksen tandem with Di2 rear shifting adapted for an 11-32 cassette plus mechanical triple front derailleur is very interesting, and I see that the stoker also gets an extra set of shift buttons. Any idea what they did with the electronic front derailleur - I understood that you cannot just do without it because the FD contains the Di2's brains - Do you know if they removed the brains and hid them somewhere in the frame?

Several years ago also saw a protoype Ritchey Breakaway tandem . . . then nothing after that.
Years ago Bruni also built a take apart tandem without S&S.
Montague had a full size (26" wheel) folding tandem but then Co-Motion built the first S&S tandem . . .
S&S is getting pricey so Ritchey may have a winner!
As for tandem converting to single . . . Bike Friday already did that and so did a couple custom builders.
Pedal on TWOgether!
Rudy and Kay/zonatandem

Saw the Eriksen tandem at the show. The person I talked to said the extra shift buttons and XTR hydraulic disc lever were for when the Stoker decided they needed a different gear or to use the brake in a panic situation. My wife (stoker) almost started crying she was laughing so hard. No way would I ever ride a tandem where the stoker could affect shifting and braking and neither would my stoker.

Say it ain't so Joe!!

There's got to be more to the story than that. Kent Eriksen and his wife are both long-time, hard-core tandem cyclists. I know the customer is always right, but there has to be some subtle nuance in there somewhere where the client's have actually learned to "cooperate" in harmony on a tandem. Put another way, giving a stoker control over a rear brake isn't all that new. Sharing shifting duties in rare, but I've seen it before. But, the mutany scenario painted at the show is just too over the top in light of how much was invested in the Eriksen. I say that only because I came very close to having Kent build one of his Ti tandems for us a while back and once again found myself getting a little light-headed when I ran the numbers. That said, dealing with Katie & Kent was a pleasure.

There is more to the story than that..........
The DI2 triple was was originally set up as a non functioning display, the people from Shimano stopped by and said they didn't appreciate it, Erickson removed the front Di2 and replaced it with a mechanical front derailer, again just for display perposes. Neither the half electronic half mechanical or the Di2 triple was functional.

The judges at NAHBS must have liked something, as it won Best Tandem. Of course, the judges may not be all up on the nuances of captain-stoker relations.

http://farm8.staticflickr.com/7208/6...c01cb88915.jpg


I had this set-up explained to me, but I couldn't follow it. There was Di2, and mechanical, and controls back and front, and brakes, both rim and disc, cable and hydraulic. Lots of cables here. It was like Three-Card Monte, only on a tandem.

http://farm8.staticflickr.com/7044/6...884341f455.jpg

Mrs. Ritterview talked to Mrs. Erickson, but no deep stoker secrets were revealed, I don't think.

A photo Mrs. R took, just after the Best Tandem award was announced. Doesn't look like the frame will be overly burdened by the tandem team.

http://farm8.staticflickr.com/7044/6...b05b96ba_z.jpg

The best take-way I got from the Eriksen tandem was the approach of using only 2 S&S couplers, which supposedly allow the tandem to be transported in a pair of Trico single-bike airline cases.

Maybe not a new idea but one I had not heard of.

Just to add to the what are they thinking on the erickson, The bike only has one set of couplers so it is not going to break down small enough to get in S&S cases, I don't get it. Parts can easily be switched out but paying for couplers and not being able to avoid airline fees does not make sense to me.

Nit picking aside the Nahbs show is a great day out. A lot of what is on display is "concept" or eye apeal for the sake of the show. Let's not discourage the exhibtors from showing tandems by cutting them to pieces because of something fun they did on a show bike.

Man I gotta learn to type faster......see post above

Well - it was the guy with the glasses in the pic that was telling me this - i'm not making it up. I asked why they would use a disc brake as a drag brake - because the tandem did have front and rear brakes. I didn't see his name tag - so I didn't know who he was.

I know that some people have had stokers that have control over a drag brake - but IMO - that's really something you would communicate like everything else - have them apply the drag brake. But Panic Brake - his exact words - WTF?

As for the shifting - well that just kinda blew my mind.

I agree - great show. That being said - there were several CF disc forks that I saw - some that had the 1.5" diameter tapered steering tube that would be awesome for tandems (i'm never giving up my dual discs). One was by Enve and one by another company I can't remember. When I asked the Calfee rep - Craig had just stepped away - if they'd ever used the Enve CX disc on a tandem he didn't know. Another was the Scrub Components rotors. I talked to them and they felt there wasn't enough market share for 203mm rotors. A shame because their steel rotors would be a nice option.
http://www.enve.com/cache/ProductTyp...20111213050337
Speaking of that - does anyone know what rotor that was on the Cyfac tandem? I didn't notice it at the show.

It is a Hope Floating Rotor (and Hope skewer as well).

http://farm8.staticflickr.com/7207/6...d0e267ec_z.jpg

203 mm is 169 grams, whereas an Avid 203 mm G3 is 192 grams.

The Co-Motion rep said that they were going to produce a front disc version of their tandem-spec'd carbon fork.

Steel rotors are everywhere available. What is needed from Scrub is a tandem version of their magnesium carrier and/or composite friction wheel material, in 203 and 220 mm. Tandems could use larger diameter rotors with less weight penalty.

http://scrubcomponents.com/assets/im..._Top_Image.png

A couple follow-ups / thoughts....

Yes, the guy in the glasses with hair is Kent and that's his wife Katie; both have pretty solid cycling credentials. Perhaps Kent had gotten punchy answering questions all day and opted to go into the art of the possible and attention-getting response mode? Guess we'll never know, as I'm just not THAT curious. But, that said....

The additional insight into the Di2 from ChiChi is what I was looking for. Something just didn't make sense in looking at how that tandem had been configured. Rear disc as a supplemental brake isn't all that unusual, but using a hydraulic with a smallish rotor looks more like someone just went to the parts shelf and pulled-off what was sitting there... kinda like the Di2: a last minute build of a new frame for the show. Even the cranks weren't lined up the way I would have expected them to be for a show bike. Nits to be sure.

While a rear disc ain't the best choice for a true drag brake it will work as a supplemental brake and/or a primary with a rim brake as a supplemental. Both of our Erickson tandems -- the '98 and '02 -- had Hope mechanical rear disc drag brakes which did what they were supposed to do... to a point. And that was to provide a little added braking power that allowed you to give your right hand and rear rim brakes a break on very long descents. However, the hydraulic is a non-starter on a road tandem and makes no sense at all due to the likelihood of boiling the fluid and either locking the rear brake or blowing a hydraulic line connector. The Avid BB7 or the Bengal MB700T (which we just started to play with) will both lock the rear wheel on a tandem with a lightweight team so: (a) needing the additional braking power isn't the issue and, (b) I don't see better modulation or (c) less hand effort as needs either. Not sure whey they didn't throw on one of those unless, as already noted, they simply bolted on what they had in the shop and/or it looked-cool.

Floating rotors have been around for a long time. We have friends who also have a '98 Erickson that was fitted with a Hope mechanical disc and a Hayes floating rotor of the same vintage. I thought ChiChi put one of the newer floating rotors on his Calfee after the dual rotor thing didn't work-out as hoped?

The pair of coupler approach was explained to me by Kent back in 2010 as a way of making it very easy to break-down the tandem so it could be put in the trunk or cargo area of just about any car, public transport, etc. For air travel, my recollection was that it assumed occasional travel where a regular bike case/box could be used for the frame, bars, etc., where the wheels went into a second, checkable bag along with other components. Again, just a very pragmatic approach for dealing with transporting a tandem where the expense associated with a second set of couplers ($1k?) might be hard to justify for infrequent air travel. Note: The ti tandem he displayed at the 2010 NAHBS show used the same two-coupler approach. It was also an award-winner as I recall.

As for best tandem, I'm guessing the judges looked past the components and did what they should have done by focusing on the execution of the frame... and, well, Kent is an icon at NAHBS. The photos clearly don't do it justice. The only thing I would have spec'd differently would have been a bi-ovaled down tube, just to reduce the cross section of that large diameter tube. But, beyond that the execution of the welds, the finish, etc. all look spectacular.

I am a little confused and will expose my disk brake ignorance by asking a question. Is the comment above due to the type of brake fluid used or does it apply to all hydraulic disk brakes on a tandem? If it applies to all tandem hydraulic disk brakes, how do bike brakes differ from motorcycle and auto brakes that use hydraulic fluid?

Maybe Shimano will get the idea and come out with a Di2 triple?:rolleyes:

great photos ritterview. thanks for posting them.

With compact cranks supplanting triples in the road market and 2x10 drivetrains displacing triples in the mountain bike market, I'm not holding my breath that sufficient demand exists to get Shimano's attention.

Note the Erikson tandem used a Di2 rear derailleur with modified, longer cage to allow the use of larger cassettes. Perhaps the after market will hod-rod a Di2 front derailleur at some point?

All closed hydraulic bicycle calipers when used on a tandem, and to a certain extent even the open systems (e.g., Magura Gustav M, Julie-Tandem, Hope 04DH/Enduro, etc) if you really, really overheat the brakes.

The difference between cars/motorcycles and bicycle systems is the lack of any mass in the rotors, calipers and other parts of the hydraulic system and -- with just a few exceptions -- the lack of a brake master cylinder that can deal with brake fluid expansion or boiling in a system that uses a very small volume of hydraulic fluid. I'd venture a guess that there's more fluid in the master cylinder on my motorcycles than there is in the entire rear brake system on our Ventana, including the fluid in the master cylinder.

So, there are two types of failures to be concerned with, and the first lead typically leads to the second. Underlying it all is simply over-using / riding brakes, which is what a drag brake is used for on a tandem.

As you over-use a brake -- any brake -- the pads will begin to glaze and outgas as the heat builds and brake fade will begin to reduce braking power. On hydraulic systems, this same heat begins to migrate into the hydraulic fluid which then begins to expand. As it expands it will begin to cause the brakes to remain applied even if you let go of the levers, exacerbating the brake heating. In turn, this causes even more heat to go into the brake system and the brake fluid will eventually begin to boil. Once the fluid boils -- DOT4, Mineral or otherwise -- you will loose the ability to apply useful brake energy to the caliper and rotor. This comes on as a spongy feeling in the brake lever sans any real braking power (very similar to brake fade with Avid BB7s) and you'll eventually lose all braking power, no matter how hard you pull the lever. Off road, where the coefficient of friction is lower, you'll typically get a locked-up wheel that drags you to a stop before the fluid begins to boil.

Bottom Line: The amount of brake energy that you need to slow a 300lb+ tandem flying along on an asphalt road is a lot higher than what you need on your typical off-road trails where the speeds are slower and the coefficient of friction is also not nearly as high. That's why you'll see folks using hydraulics on their off-road tandems - typically open system brakes like the ones I've mentioned -- but not on their road tandems.

It is purportedly in the cards, but not on the front burner just yet.

I noticed the skewer but didn't look hard enough on the rotor. I'm surprised it works without modification to the Caliper. Didn't someone on here try it and had to modify the caliper? I'm not so concerned about weight - but more so with lateral stiffness of the rotor as well as it not being as prone to slight bending.

That's good to hear - they were busy with people so I didn't have an opportunity to talk to them. I just want another option other than the Wound up.

I talked to the guy about that - he said he didn't think that they work that well on a tandem even at the 203 size (didn't talk about anything bigger) as they wouldn't dissipate heat as well as the steel or brake as well.

I know some of you are concerned about saving weight - i'm not that concerned about a few grams here and there. In fact - my brakes work so well - I really don't need to change anything - but I would like a 2 piece rotor more for durability than anything else.