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Tandem Cycling A bicycle built for two. Want to find out more about this wonderful world of tandems? Check out this forum to talk with other tandem enthusiasts. Captains and stokers welcome!

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Old 09-08-12, 04:10 PM   #1
dfcas
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New Cannondales Coming

My local dealer says that Cannondale will have tandems in December 2012, in road and 29'er mtb geometry. No word on whether they will offer framesets or only complete bikes, but I do hope this turns out to be true.

These will be Asian sourced, and he was not sure about changes.
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Old 09-08-12, 10:00 PM   #2
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Another American icon outsourced.
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Old 09-09-12, 11:32 AM   #3
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Hopefully they'll have some info on this at Interbike.
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Old 09-10-12, 05:17 AM   #4
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I heard Mel from Tandems east a the ETR speak about some info on Cannondales new 2013 Tandems. I think he said that there would be 3 new models. A road tandem with BB30 bottom bracket, a road model with straight handlebars like the current Street model and a mountain bike tandem.
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Old 09-10-12, 08:32 AM   #5
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Looking forward to seeing how these turn out.
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Old 09-10-12, 03:14 PM   #6
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I heard Mel from Tandems east a the ETR speak about some info on Cannondales new 2013 Tandems. I think he said that there would be 3 new models. A road tandem with BB30 bottom bracket...
That is big news in a lot of ways.
  • First, that Cannondale has not abandoned tandems. The details trekker relates through Mel are not vague assurances, but specifics that bespeak of definite action on C'dale's part. Cannondale had last made a tandem frame in the US in 2009, prior to their US production shutting down, and might have left it at that, but didn't.
  • The BB30 bottom bracket means that a new frame is being designed de novo. Cannondale might have had the old frame merely made in Asia, but isn't.
  • Cannondale is renowned (with a veritable cult following)for their aluminum racing frame, the CAAD-10. It weighs about 1150 grams (vs. 700 g for their carbon Super Six Evo). Whoever designed the CAAD-10 may well design the new RT2, and what is this person to be told "make it heavy, flexy and slow"?. If they are to design a new frame, it will probably be done well.
    Why not? They have the unique capability, and I don't think that a good design in an aluminum frame is much more expensive to manufacture than a mediocre one. The 2013 'dale RT2 frame might be a very good aluminum tandem frame, and will almost certainly be a great value.
  • If the RT2 has a really good frame, is C'dale really going to adorn it with the hefty Fatty R fork? C'dale will probably design a new fork for the new frame. If it gets a carbon fork, that would make the RT2 very attractive.
  • The BB30 bottom bracket will require a BB30 tandem crank. Presumably this would be the FSA SL-K. However, C'dale makes the well-regarded BB30 Hollowgram crank, with which it equips its higher-end bikes. Perhaps C'dale might want to offer it in a tandem version, which would be a boon to tandem crank choices.
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Old 09-10-12, 03:51 PM   #7
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For me, the BB30 bottom bracket would be a negative point, not a positive. Here are the options that this would leave you with for cranks:

I believe FSA's BB30 tandem cranks and Lightning's are the only tandem-specific models with a 30 mm axle. Other than those, there are adaptor cups that you can put into BB30 bearings that reduce the internal diameter to 24mm and make the width the same as with Shimano's threaded, external-bearing cups; I am therefore hopeful (but not certain) that you could use Shimano's new Ultegra-level tandem cranks in the Cannondale frame by using the BB30 bearings and adaptor cups.

Alternatively, to give you further crank options, you could use a single-side drive setup with two single-bike BB30 cranks, with the main drawback being that you would be limited to only two chainrings. However, if you want to keep the low-end gears while only using two chainrings, then you can use a triple crank and only use the inner and middle rings and put the timing chain/belt in the outer position - this is currently the setup we're using on our Co-Motion so that we can use single-bike cranks and so have more options with crank lengths (chainrings are 26 and 42 teeth, cassette is a 10-speed 11-34).

Life would still be made easier if Cannondale just used regular 68mm threaded bottom brackets. I generally dislike Cannondale due to their "System Integration" - I prefer to call it "System Incompatibility". BB30 is something they started (with FSA) and I agree with Shimano's response on the matter when they were asked why the new 9000-series Dura Ace group still has no BB30 crank - they believe that BB30 is pretty pointless in terms of crank/axle stiffness, and aluminum axles with carbon spiders/cranks are not any better than a well-engineered aluminum spider/crank and steel axle. I work in a bike shop (where we sell Cannondale amongst other brands), and I'd be happy if I never had to deal with another creaky BB30 crank/bearing setup again. The total system weight for BB30 might be 50 grams lighter, but that is not worth the compatibility and maintenance problems that it causes. Heel clearance is another touted advantage of BB30, but this is only important for a very small minority of people.

I certainly hope that there won't be any other special "System Incompatibility" features on the Cannondale Tandems - hopefully they'll at least use a standard-sized steering column on the fork so that people have a completely free choice of stems (this is a big problem with many of Cannondale's forks like the Fatty and Lefty).

Last edited by Chris_W; 09-10-12 at 04:08 PM.
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Old 09-10-12, 05:07 PM   #8
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How big would a BB shell be that accepts an eccentric that accepts a BB-30 BB? Maybe they will have a usable eccentric this way.
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Old 09-10-12, 05:33 PM   #9
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How big would a BB shell be that accepts an eccentric that accepts a BB-30 BB? Maybe they will have a usable eccentric this way.
Wouldn't the eccentric be the captains BB and the BB30 the stoker's?
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Old 09-10-12, 08:04 PM   #10
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I live in the USA. I'm flying the US flag on this topic. To many good American manufactured machines to bother with anything made overseas. If the US bikes cost more, I'd either find the money or buy a nice used bike.

Asian aluminum Cannondales have done nothing to impress me. I have repaired enough of their carbon fibre frames to keep them low on the want list.

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Old 09-16-12, 02:17 AM   #11
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Interbike, Interbike... where art thou, Interbike? Anyway... three MY2013 tandems? Wonder if the MTB 29er version will "bouncy both ends"? The 80mm/130mm travel "Lefty Supermax" is "as strong as a double-crown DH fork"... so that would imply said fork is at least strong enough for an MTB trail tandem. Hmmm.
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Old 09-16-12, 05:17 AM   #12
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Interbike, Interbike... where art thou, Interbike? Anyway... three MY2013 tandems? Wonder if the MTB 29er version will "bouncy both ends"? The 80mm/130mm travel "Lefty Supermax" is "as strong as a double-crown DH fork"... so that would imply said fork is at least strong enough for an MTB trail tandem. Hmmm.
I have worked on enough Lefty forks, having to pull them completely apart to the roller bearings for repairs. No interest from this team to go there with a Lefty. As for the 29 platform, it works for a lot of riding areas. We have thousands of miles on a 29'r tandem. We know how they feel and react. There is only so much design parameter available in regards to front end geometry. For several reasons we are sticking with 26" wheels. The suspension allows better compliance than 29 hardtail. The 26" wheels are more flickable in true singletrack, the 26 rear wheel when cornering is more predictable when sliding, and is easier to slide and get the bike turned. Speed wise, our efforts and results are similar on smooth terrain. Add bumps and the more complicated full suspension get's the job done with less fuss.

The interesting item though about a new Cannondale MTB tandem will be to see if they make their own crankset, or someone else is stepping into the game.

It is possible if Salsa releases their off-road tandem, Cannondale releases a new true off-road tandem, and I believe Santana has their new entry level bike available, it could be an interesting year for long off-road bicycles.

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Old 09-16-12, 06:34 AM   #13
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Another American icon outsourced.
Without intentionally doing so, I find a surprising number of US products on our bikes. More if you include high wage Japan, Australia, and western Europe.
I find it interesting that a search for custom or quality gave these results. Tandems help I suppose with the small niche market being dominated by the US.

I believe that manufacturing in the US is actually on the rise for the first time in decades. Velocity moving to the US is an example of the current movement of some high quality manufacturing back to the US.


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Rims: Velocity, older Mavic
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Old 09-16-12, 10:28 AM   #14
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It is possible if Salsa releases their off-road tandem, Cannondale releases a new true off-road tandem, and I believe Santana has their new entry level bike available, it could be an interesting year for long off-road bicycles.
Whilst I'd like to see the Salsa tandem come to fruition... I wager that the Salsa suspension fatbike will come to market first... *hunch*

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More if you include high wage Japan, Australia, and western Europe.
If you can include Japan, then it'd be wrong to not include the "other" China, aka the Republic of China, aka Taiwan, which on a GPD purchasing power parity per capita basis, is actually higher than Japan. Indigenous brands include Giant and Merida. Kenesis manufacture for (non-exhaustive) Diamondback, Felt Bicycles, GT Bicycles, Schwinn, Jamis, K2, Raleigh, Trek, and Kona. And there are also some small bespoke builders doing steel/stainless-steel frames.
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Old 09-16-12, 01:26 PM   #15
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Whilst I'd like to see the Salsa tandem come to fruition... I wager that the Salsa suspension fatbike will come to market first... *hunch*
From the posts I have seen about Salsa's tandem MTB, it's interesting but really is designed around the Rohloff. The all right side drive is cool. We tried it for many miles off-road and when conditions and the least amount wear come together, well it is crap.

Right side drive with a Rohloff off-road is smart, just expensive. Alex @ MTBTandems.com built a Rohloff rear 2X upfront, 28 speed Fandango. Not sure where the gearing fell when compared to what Rohloff recommends or where Salsa built their bike.

Interbike is soon enough that myths will become fact or fiction.

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Old 09-17-12, 05:24 AM   #16
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From the posts I have seen about Salsa's tandem MTB, it's interesting but really is designed around the Rohloff. The all right side drive is cool. We tried it for many miles off-road and when conditions and the least amount wear come together, well it is crap.

Right side drive with a Rohloff off-road is smart, just expensive. Alex @ MTBTandems.com built a Rohloff rear 2X upfront, 28 speed Fandango. Not sure where the gearing fell when compared to what Rohloff recommends or where Salsa built their bike.

Interbike is soon enough that myths will become fact or fiction.

PK
I'm actually surprised the apparently un-beefed-up Salsa Alternator dropouts on their prototype tandem hasn't blown up already, though those swing dropouts can easily accomodate cassette hubs or IGHs with ease. I wouldn't personally say it was "designed for" either way.

The Salsa was set up 41/16, which is inside the safe 2.35 ratio range. The smallest Rohloff sprocket is a 13t, so that means a 30t chainring. The small ring of most MTB double cranksets fall within that value within 10%... after all, Rohloff have their torque limit based on the power output of two strong riders at 500W each. As torque is proportional to power at any given RPM, an average club cyclists puts out about 300W, so really... you could undergear a Rohloff probably by a factor of at least 1.3 and maybe up to 2 and it wouldn't be an issue for most teams. Could get some more margin if you run cranks slightly offset, though some teams don't get on with that at all (I'm personally okay with it).

I'm personally interested how long a Shimano Alfine-11 would last on a tandem... though the only annoying thing is the 42mm(?) chainline which makes an all right-side drive (as far as my brain can process) a rather tricky one.

So errm, yeah... come on Cannondale, show us your hand at Interbike!
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Old 10-11-12, 04:51 PM   #17
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Ominously, Cannondale has their 2013 bikes up on their website, but the Road Tandem 2 is not among them.

There is still a listing for the RT2 in their 2012 bikes, but much of the information previously available is removed.

So far, with the 2013 RT2, all is rumors. Is there any official word on the RT2? Any solid evidence (like a pic of the new frame)?
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Old 10-22-12, 03:20 AM   #18
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External bearing bottom brackets are fools errand. Anyone advocating that bike being designed anew should use this folly in search of a problem doesn't understand damn thing about crank design, bearings, or Q-factor.

The only concerns that like external bearing BBs are component manufacturer's who simply want to make one size fits all products. External BB are a sign to me of a bike one should not buy. Always the wrong design, wrong crank, and wrong solution.

I love BB30, but absent that I'd always go retro with a square taper.

I have one bike with a Race Face Turbine crank with external BB. It is idiotic.
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Old 10-22-12, 09:21 AM   #19
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External bearing bottom brackets are fools errand. I love BB30, but absent that I'd always go retro with a square taper.
What???

What's not to like about external bbs? Current Shimano and Campag stuff just works, the sealing works, the crank is light and stiff and very simple to maintain. The same can't be said for BB30 - half of the installations creak, it needs a press to replace the bearings and on a tandem it's a dumb idea since it limits keel and down tube dimensions to something like 55mm to mate with the 60mm wide shell. Then you need a larger eccentric too.

A better compromise would be BB90 - drop-in (not push fit) bearings supported by the frame and a nice wide shell to support asymmetric down tubes, keel tubes and seat tubes. Just look at the latest Trek Madones - their top end frames test extremely well on weight and stiffness partly since they start from a great structural design.
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Old 10-22-12, 03:34 PM   #20
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Per Cannondale cust support today there will NOT be a Cannondale Tandem in 2013!! They referred me to their sister company's Schwinn Tango
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Old 10-22-12, 04:10 PM   #21
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Another American icon outsourced.
I agree, so sad not enough demand I quess to keep them USA built or just plain out more profit being built over sea's......

Ride Safe,
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Old 10-22-12, 06:40 PM   #22
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Per Cannondale cust support today there will NOT be a Cannondale Tandem in 2013!! They referred me to their sister company's Schwinn Tango
Isn't customer support usually the last to know something?

A Cannondale insider is needed!
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Old 10-22-12, 07:45 PM   #23
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Isn't customer support usually the last to know something?

A Cannondale insider is needed!
True many times with Cannondale.

The bikes when new were a good value, most times can be found used. I know it does cost more, but a new quality American made tandem is still attainable and used ones in excellent condition sell for similar money as the new Cannondales did.

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Old 10-29-12, 11:40 PM   #24
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What???

What's not to like about external bbs? Current Shimano and Campag stuff just works, the sealing works, the crank is light and stiff and very simple to maintain. The same can't be said for BB30 - half of the installations creak, it needs a press to replace the bearings and on a tandem it's a dumb idea since it limits keel and down tube dimensions to something like 55mm to mate with the 60mm wide shell. Then you need a larger eccentric too.

A better compromise would be BB90 - drop-in (not push fit) bearings supported by the frame and a nice wide shell to support asymmetric down tubes, keel tubes and seat tubes. Just look at the latest Trek Madones - their top end frames test extremely well on weight and stiffness partly since they start from a great structural design.
Well it depends on what you mean by a dumb idea. The funny thing is when Klein was using press in bearings on his bottom brackets the idea was considered a folly. Everyone threw their arms up in the air about how the aluminum bottom bracket shells would fatigue from having bearings pressed in and out. I've never heard of a Klein failing at the BB because of having bearings pressed in/out.

In the commercial world machine shops press bearings into hi-tech aluminum/magnesium housings and they aren't particularly careful about it. It is almost unheard of for a core to be scrapped. It is just a near myth. Besides, how many times do you really need to replace your BB bearings even if you ride 20,000 km a year over the lifetime of the bike.

On a properly designed tandem, the argument for a sensible (that is non-external BB) makes almost no sense. On a tandem, as you point out you can design an even larger BB and the bearings are held in the eccentric, not pressed into the shell.

External bearings are a train wreck. A compromise of new technology with an old standard. External BBs affect the shifting performance of a front derailleur. If you were to ask a Shimano or Campagnolo engineer who only worked on front derailleurs he would rail about how external BBs were "ruining" the perceived performance of his brilliant designs.

What "didn't work" about a traditional square taper BB? I'm not saying I like that design, I'm all for moving forward, but using the smaller BB shell from the square taper era and moving the bearings outboard is heavy, clumsy, increases Q factor, and causes ergonomic injuries. There is a reason that cranks used to include Q-factor in their specs. That has been forgotten of late.
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Old 10-30-12, 02:39 AM   #25
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How does an external BB affect the front shifting? Is there any data to prove that a narrow Q factor is better? I have had or have bikes with all the BB styles mentioned ( I even have a Klein) and do not think there is any significant performance difference between them. The external BB is definitely the easiest as far as servicing goes though.
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