(I should introduce myself since I'm new to this forum, but not to pedalling.) Hi, my name is Dan and I have a 'tandem problem': My wife and I love riding two-up! (Currently on our Santana Visa.)
We're doing the 2007 LOTOJA this September, and while I've ridden that for years, this will be a first for me on a tandem, and a first ever for my wife. So we thought it would be cool to get a new racy tandem. After all, it should be easy to choose one and order it.
I've read lots of opinions here and I've been getting an education on the variety of tandem designs available while looking around on the web over the winter. Its nice to have such a diverse selection for a small market. I've been impressed with the obvious: Open/ compact tandem frames have tons of potential for go-fast machines.
Of course tubing material and diameter will never converege. But results of recent studies posted here, and the few production 'compact tandems' make a lot of engineering sense. The compact open frames with appropriate tubing diameters just look and feel right to me. But the designs are also a bit "young".
It looks like the handful of frame builders pursuing this frame style are ahead of the game for race tandems. I'm excited to see how race frames morph in this direction and dial-in their designs over the next short years.
And I still don't know what to buy for this season.
The BikeForums Team
-adv-
This is an archived thread, you can find the full version of this thread, with images, links and more content here.
Could you elaborate on what you mean by 'open' design. Compact I get, but your statement about the 'few' tandems designed that way is a little surprising. I am a bikie from 'back in the day' when 25" and larger frames were common. After a two decade layoff I come back to discover that a 23" frame is gigantic and the norm is more like 21", 22". Everything looks 'compact' to me. My Raleigh Coupe has an XL front compartment and I think it is 21" Extra large? And pretty much everything is designed with sloping top tubes. So, what exactly are your ideas on current designs?
H
zonatandem
Open frame design eliminates the 'lateral tube' that runs diagonally from the headtube, thru middle of capt's seat tube and down to the stoker's bottom bracket. Attached photo of open frame design tandem.
A 'compact' open frame design has the top tube running at a significant angle from the headtube down to stoker's seattube.
zonatandem
To our knowledge, the only current tandem builders that have utilized the open/compact frame design are ariZona Tandems, Bruni, Calfee, Co-Motion, daVinci, Paketa. There may be more, as the trend is catching on.
dbohemian
Hey Now! don't leave Bohemian out:D
Throughout the history of tandems there has been open framed designs. Rene Herse and Singer of the 40's-50's for instance.
In order to recoup some rigidity lost through the small diameter tubing tandems then gravitated towards extra bracing in the form of more and more tubes. Marathons, double marathons, direct laterals etc.
This all worked well to increase stiffness.
Later, when larger diameter tubing became available some tried to use it more efficiently, that is the open framed tandem but this time with more efficient tubing. First that I know of was Tom Bruni, who has since passed away, but I believe was the original person to use large diameter 4130 aircraft tubing to create the new designs.
Next at about the same time was Victor Chang (Concept technologies) and myself who created what we are now seeing as a trend in tandems. The oversized-open framed geometry.
Craig Calfee (whom I think is awesome) flat walked up to me at a show and said "hey that makes a lot of sense, I think I will do that myself" and thus we now see the open framed Calfee's.
After a bit, things just snowball and now there are a number of manufactures making the general design.
In my opinion, it just makes more sense. A better use of material, more efficient with less overall stress. The proof is in the riding and most people who have some experience with a well designed open frame will tell you it rides just like any other tandem which is what it was supposed to do.
Dave Bohm
Bohemian Bicycles
P.S. I am sure others were doing it too, maybe even before Tom. Engineering problems tend to find common solutions.
dbohemian
To our knowledge, the only current tandem builders that have utilized the open/compact frame design are ariZona Tandems, Bruni, Calfee, Co-Motion, daVinci, Paketa. There may be more, as the trend is catching on.
Tom Bruni passed away in 2005 from an altercation with a vehicle. He was extremely inventive and a nice guy.
http://www.onelesscar.org/TopLevelDi/TomBruni.php
TandemGeek
So we thought it would be cool to get a new racy tandem. After all, it should be easy to choose one and order it...
Not sure why it's so hard...
1. Establish your upper cost limit (and your lower cost limit if you're looking to make a statement)
2. Decide how important weight is to you then recognize that the difference in frame weights between the light and superlight is just a pound or two... most of the weight savings are coming from component selections, just as they do with the superlight solo bikes.
3. Reconcile any biases you may have for or against frame materials or construction methods
4. Evaluate the experience and reputation that each builder has relative to how you intend to use your tandem.
5. Call and personally speak with the one or two builder's principles left on your short list about what you're looking for in a tandem and then pick the builder who you feel you "click with" the best. This could be hard as the builders who would likely end up on your short list are all great at working with clients but, at this point you'd be hard pressed to make a mistake unless you really screwed up on your requirements and put too much emphasis on light weight go-fast goodies vs. getting a proper fit.
And I still don't know what to buy for this season.
Just pick one. After all, how many single racing bikes did you have to buy before you got the right one.... or are you still trying to figure out which one is "the best"? After all, once you hit a certain level bikes become analogous to fine wines, single malt scotches, or anything else that is highly refined: none of them are really THAT bad or that much better either. They're just different and the only way you can decide if you like one more than another is to ride one for a while.
zonatandem
Bohemian:
My apologies for leaving a fellow Tucsonan off the list that builds open frame tandems! That's what happens when I don't have my thinking cap on . . .
Met Tom Bruni years ago and test rode one of his open frame tandems . . . no hills around . . . so we honked up a 4 story parking garage. Very pleasantly surprised! Tom was a real advocate of that design and had a significant linfluence on the resurgence toward the open frame concept.
Pedal on TWOgether!
Rudy and Kay/zonatandem
mrfish
In my mind a nice racy tandem has road bike type components; 700c wheels, caliper or perhaps disc brakes and drop bars. What differentiates a merely nice bike from a gorgeous bike is that the gorgeous bike fits together as a coherent concept, whereas the nice bike is a component bin bitsa.
Some thoughts:
- Think of what you're going to do with the bike. If it's time trialling on smooth flat roads, the bike will look much different to something you're going to ride up the Alps on.
- Don't spend all your money on an exotic material frame. A project one paint jobbed or custom resprayed trek T2000 will look more exotic, and will leave you with $1000s to spend on components which will save much more weight and look cooler than a titanuim carbon frame ever will. Caveat: Provided it fits.
- Do spend a decent amount on wheels. The Rolf or Bontrager wheels seem like the raciest choice to me, though they are a bit heavier than light tandem specific handbuilts. If you have more money a set of Lightweight wheels (the German all carbon ones) on a tandem would be uber cool. Using single bike wheels is not a good idea.
- Use weightweenies to help you with gram shaving. Work out the cost of components per gram saved to see where you're getting value for money. You may be surprised to find you can save 10g/$ in inner tubes but only 0.2g/$ by upgrading parts from groupset X to Y. Normally the best value weight savings come from inner tubes, tyres, wheels, saddle, seatpost, crank. Carbon bottle cages are normally amongst the worst buys.
- Don't use the lightest possible captain seatpost. Guess who's using it to keep themselves on the bike.
- Make sure the saddles and stems, seat colour and bar tape match. Also avoid red, white, yellow blue manufacturer's logos on parts if the frame is green to avoid looking like a parts bin special.
- Think about what cranks and drivetrain arrangement you want to use. Single or double sided? Tandem specific or chi chi road cranks with helicoils? Unfortunately recent Shimano and Campag single bike components won't work as there is no way (short of significant machining) to join two right hand cranks together on the new designs. Octalink tandem carbon FSA cranks are available I think for maximum bling.
- Gears are probably going to be either Shimano or Campagnolo. SRAM would be interestingly different though.
- Once you've spent all that money on saving weight, don't add a rack, pump, bento box, massive spanner set to the back. If it doesn't fit in the pockets in your jerset you shouldn't take it.
With all that said, you don't have to do it all at once. I'm gradually upgrading my 2005 T2000. It's basically stock apart from saddles, stems and bars to get it to fit. In about a week it will have an AME carbon fork and caliper brakes, with the next upgrade perhaps in a few months being to get matching Thomson stems and seat posts when they're cheap on ebay. Next perhaps a closer ratio block and narrower tyres and lighter tubes when the current ones wear out.
Coming back to the frame, if you think the designs are immature, you should consider an off the peg T2000 or co-motion as it will get you a racy ride for now, then you can re-sell and upgrade the frame in a few years when designs have matured.
dbohemian
[/quote] Coming back to the frame, if you think the designs are immature, you should consider an off the peg T2000 or co-motion as it will get you a racy ride for now, then you can re-sell and upgrade the frame in a few years when designs have matured.[/QUOTE]
The open frame design is 100+ years old. Current modern OS open-frame is 18-20yrs. They are proven. Question is, why is everyone being so slow adopting them?
I agree that any of the above choices are excellent too.