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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 11-15-07, 10:32 PM   #1
zonatandem
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16-lbs tandem?!! Yup!!!

While at the El Tour de Tucson Bike Expo today picking up my riding packet/number, for my 24th El Tour, did my usual socializing/visiting with friends and vendors.
So yes, there was a 16 pound tandem on display . . . built by Rue Sports of Tempe, AZ. This was a full out racing machine built for 2 small female tandemistas. Decaled as an 'Ubertandem' Yin/Yang model it featured a latless carbon fiber frame, one chainring (told you it was a racing twicer), same-side drive and the SRAM Red gruppo + daVinci cranksets.
Last year Rue Sports had a 20-lbs tandem on display at Interbike . . . Brent Ruegamer is the builder/designer. Sorry, no photos.
V-e-r-y interesting!
Pedal on TWOgetrher!
Rudy and Kay/zonatandem
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Old 11-16-07, 12:20 AM   #2
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Sounds nice
Might be a bit out of my price range this week
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Old 11-16-07, 07:06 AM   #3
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Let's run the numbers....

Notional Superlight Calfee/Zona/Machiatto/Paketa Tandem (Some assumptions here**)
26 lb = 11,804 grams
Frame Alone = ~2,815 grams**
Everything Else = ~8,989 grams

Notional Yin Yang Tandem
16.5 lb = 7,491 grams
Rue frame = ~2,000 grams**
Everything Else = ~5,491 grams

Notional Frame Savings = 815 grams / 1.8 lbs
Notional Component Savings = 3,498 grams / 7.7 lbs

I would have sure liked to know more about the components since that's where 81% of the 9.5 lbs of notional weight savings come from. Single-side drive and a single chain ring won't take all that much weight out of a set of daVinci cranks, e.g., ~100 grams for a granny ring and smaller spider remembering that daVinci cranks use spiderless timing rings. And just how small was the frame? Their stock geometry shows 27" stoker compartments and companies like Griffen have used even shorter stoker compartments for their 'race' tandems. The frame cost and total bike cost would also have been worthwhile data points.

So, any other details that could have given this amazingly light tandem some context in terms of componentry, dimensions or costs would have really make this far more interesting and informative.

Obviously, given that I'm in the midst of gathering components to use on our Calfee I'm somewhat sensitive to the cost / weight ratios, noting that I've seen how you can go from a 300 gram / $100 stoker stem to a 180 gram / $350 stoker stem ($2 gram), or from a 150 gram / $150 seatpost to a 90 gram / $350 seatpost ($4 gram), perhaps a 41 gram / $11 stainless steel water bottle cage to a 22 gram / $129 carbon model ($6 gram), all the way up to changing from a 98 gram / $129 Chris King alloy headset to a 102 gram / $259 Chris King Ti headset (????) in your efforts vanquish weight from your tandem. My goal is to make all of my choices cost-neutral and/or off-set higher-end components through Ebay, clearance sales, etc... which has been going quite well.

Anyway, that's just my mindset at the moment and that's why I would have been interested in the additional details. Most of the data on their Web site appears to be either out of date ($1,800 for 6 Ti couplers... I wish!) or missing, e.g., downloadable order form. Regardless, thanks for sharing just the same.

Last edited by TandemGeek; 11-17-07 at 05:35 PM.
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Old 11-16-07, 05:09 PM   #4
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Fully agree on the g / $ equation. IMO there seems to be a point of diminishing returns, after which you get lighter, but not by much.

I would be interested to see what you are going for.

Regarding stoker stem, why don't you use a standard stem with shim? A syntace f99 is mid-priced and genuinely weighs 100g. You could couple that with a f139 up front for lowest weight at reasonable cost. Matt finish will also look good with your naked carbon bike.
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Old 11-16-07, 05:52 PM   #5
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Weight weenies!!!
;-)
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Old 11-16-07, 10:22 PM   #6
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The website for Rue Sports does seem to be a bit behind, but then whose isn't.
Frame size (guesstimate ) was 18 x 18" and was built for 2 light successful female racers. Did not have tape measure, but wheelbase looked bit shorter than conventional 69".
While weight may not be everything, it certainly must influence us or we would not be buyin ever-lighter/newer bikes!
For more $$ you get le$$ (weight), whether it's in frame/components.
Hefted that Uberlight tandem and yup, 16 lbs was right in the ballpark.
Seems they've built a second racing tandem with S&S (for rear section only), so they can change it it for road or track racing.
Builders tend to show of their latest/best/lightest at these events.
Suggest you query Brent Ruegamer if you are interested in more detail.
Just thought we'd let you know what we spotted.
BTW, talking with Craig Calfee, he mentioned that the bamboo tandem frameset price coming online soon will be the same as the c/f latless . . .$3,995.
After test riding the 'boo single, believe that bamboo is mother nature's answer to carbon fiber. Nice!
Pedal on TWOgether!
Rudy and Kay/zonatandem
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Old 11-17-07, 01:31 AM   #7
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Regarding stoker stem, why don't you use a standard stem with shim?
Standard stems aren't long enough... I need 162mm of horizontal stem length for Debbie's 30" stoker compartment.

I know this sounds pretty long, but we came to prefer the longer stoker compartments on our tandems so that Debbie can replicate her single bike riding position without 'spooning' my backside. The loss of the 1.5" from our Ericksons will put her handlebars right at the back edge of my saddle which, while it's a compromise, will still let her see her computer except when we're climbing and give her most of the 'breathing room' that she's enjoyed on the Ericksons.

Last edited by TandemGeek; 11-17-07 at 06:21 PM.
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Old 11-17-07, 04:29 PM   #8
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That's going to be a nice bike, very close to what I might choose, with only real deviations being personal preference items relating to contact points.

I also like the Thomson components, particularly for the captain's seat post - the idea of having a cf seat post to which the stoker's handlebar is attached makes me uneasy. Plus unless you spend silly money for an AX lightness, the alternatives aren't significantly lighter. Third plus point is that it's structually more efficient to have an inline post and 1 deg more layback in the frame rather than a kink at the top of the seat post, which you can specify as your bike is custom.

Only other question is regarding the wheels - I retain a healthy scepticism that the Vigors can somehow be stronger at 1800g ish than any other well-designed and built wheels of roughly the same weight using the same width rear hub. Also previous survey results weren't stellar.

I would save the money and put a rear unidisc cover on your existing wheel, which is almost free speed. On the tandem you won't notice the additional weight and wind effect. At the front I would be tempted to spend some money on a Zipp 404 clydesdale tub wheel.
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Old 11-17-07, 05:02 PM   #9
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... the idea of having a cf seat post to which the stoker's handlebar is attached makes me uneasy.
FWIW: I had Easton EC70s on our Ericksons as stoker and captain's seatposts for 5 years without any issues. However, as mentioned in the past, we're a relatively lightweight team and Debbie is hardly one to stress her handlebars. Therefore, our experience should not be given too much weight (no pun intended) by other teams who don't fall into the same description. The FSA SK-K seatposts that replaced the EC70s aren't as light and seem more 'brittle' but, after 1/2 a season, they're doing fine... well, except for the zero-setback stoker post head that came loose: the Etailer & FSA quickly and easily replaced it under warranty.

All that said, I'm very hopeful that I'll be able to use the Thomson posts for a number of reasons: light, stiff, beautiful, and made right here in Georgia just about 2 hours away from home. If it turns out that I need a set-back post chances are I'll go with the Easton EC90s. We'll see.

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Only other question is regarding the wheels.
Well, as noted, the default wheelset for the bike will be the White Ind / Fusion kit which will support our Avid disc. If I do go with one of the other wheelsets they will truly be acquired to specifically investigate and satisfy my curiosity with regard to how they perform and hold up compared to what will be a pretty-darn efficient conventional wheelset.

The Rolf vs White/Fusion would actually be a really good comparison since they'll have about the same static weight. Therefore, any "boost" in performance should be directly attributable to the spoke configuration and not a rotating mass / acceleration placebo vs. a heavier set of 40h conventional wheels that many folks moved from when they acquired their first set of Rolfs. The Topolinos are equally intriging, if not moreso than the Rolfs since they truly do represent some way out of the box thinking and innovative applications of new technology.

Again, I'm somewhat constrained by shallow pockets so all of this may be a moot point for the next year. In the mean time, we'll most certain be well-served by the conventional hoops.

Last edited by TandemGeek; 11-17-07 at 05:32 PM.
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Old 11-17-07, 05:52 PM   #10
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Campagnolo Record Front Der. / Ti Triple
There is no Campy Record front triple, best they offer for that is Campy Comp.
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Old 11-17-07, 06:10 PM   #11
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There is no Campy Record front triple, best they offer for that is Campy Comp.
New Old Stock... It's a beautiful thing.

I snagged what must have been one of the last 35mm clamp-on 2005 models (FD-RE3C5) still floating around. FWIW, I mentioned this in another thread but none of the Record stuff I have is new-new. Levers are '06 take-offs in like-new condition that came with a new cable set, rear derailleur in an '02 model that was already mine and came off the '98 Erickson which now has a new Chorus RD picked up from a friend who didn't need it. Record Ti brakeset is nearly new from before they changed out the rear differential to a single pivot, and so on. I already had an extra set of daVinci 170mm front cranks and a new set of 34t timing rings, so only 1/2 of the cranks will be new-new along with a new set of FSA rings.

Mr. Fish asked what I was going for and, to be frank, the real goal is to keep the cost of acquisition low moreso than the weight.
Attached Images
File Type: jpg TiFD.jpg (78.9 KB, 63 views)

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Old 11-18-07, 12:08 PM   #12
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New Old Stock... It's a beautiful thing.
Is the capacity really only 15?

http://biketiresdirect.com/productde...TR&tn=11849357
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Old 11-18-07, 12:26 PM   #13
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Is the capacity really only 15?
That's clearly a misprint where someone used the 15t capacity and 54t max chain ring specs for a double instead of the triple FD.

Mine is a traditional Campy Triple with 53t max chain ring and 23t capacity.

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Old 11-19-07, 04:42 AM   #14
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Apologies for my ignorance but what are unidisc covers? I've been looking for a rear road disc for my tandem and have only found the Corima C+ double skinned carbon. But I'm concerned that if it punctures, the wheel itself could be trashed. An expensive puncture! I'd consider covering my solid rear wheel with some kind of cover but it would appear that this isn't as straight forward as I thought it would be due to the lenticular nature of the wheel. Are Unidisc Covers exactly this? I've done a quick look on google but didn't come up with anything.
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Old 12-01-07, 05:52 PM   #15
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Unidisc is a now discontinued very light fabric wheel cover. They were big in the 1990s and now probably available through friends who have them in their garage somewhere or ebay. Have another look on google. Best pic is at my friend Rob English's website, which is worth a read if you're at all into bikes. http://rob.bikerevuk.com/mybikes/tt.html

My experience was that the extra rotating weight is barely noticeable, and is more than offset by the extra speed you gain. I didn't do any measurements as it was patently obvious when riding the bike that it was faster than before.

How does it work? In the package you get a circle of rubberised lycra with a drawstring, a length of 3mm dia aluminium rod and some plastic clips. The clips slide onto each spoke then go over the nipple, leaving a protruding hook. To fit it there are 4 steps.
1. Put the clips on each spoke so that the hooks alternate to each side of the wheel.
2. Cut the rod to length and fix both ends together with a plastic pipe to make a hoop. When the hoop is the right size it should fix securely under the hooks on the rim. Some iteration is required to get it exactly right.
3. Take the hoop off the wheel. Lay the hoop on the lycra and pull the drawstring tight to make a tensioned skin. Tie off the drawstring.
4. Refit hoop to wheel.
Repeat for the other side.

To pump up the tyre you just pop off 1/3 of the non drive side disc. To fit the drive side disc you can take off the cassette or if you have a clean <23t cassette you can stretch it over. Dead easy.

In my experience they work very well, 95% as good as a disc wheel if you set it up properly and take time in stage 2. Other trick is to use a slightly v-sectioned rim as it helps the hooks lie straight and to use a wheel with 32 or more spokes as it helps hold the hoop.

Those who have spent $$$ on a disc wheel tend to ridicule them, but then they would.
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Old 12-01-07, 07:28 PM   #16
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Caveat: beware of crosswinds . . .
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Old 12-01-07, 08:28 PM   #17
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Must be nice, a tandem for ballerinas. The wife and I and our gear pushes 500 lbs and my weight has more metal bending Karma then other peoples' weight so . . .
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Old 12-03-07, 03:45 PM   #18
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I rode a Unidisced rear wheel for 2 seasons when doing all sorts of short and medium distance time trials in all weathers, including lots of wind and often rain, normally in the early season hilly TTs. I was riding a road bike with tri bars, which is not the most stable machine.

In my experience they would be safe for any experienced cyclist in most conditions, particularly given the larger mass and longer wheelbase of the tandem. First ride may be a bit sketchy, but after a while you learn to trust the force on the disc and lean on the wind. Only in very gusty conditions or on very busy roads or in large groups would I not ride the disc on the tandem. Free speed is hard to say no to. Best test it and see what you're happy with.

Other benefit over a disc is that if the wind is awful you can always take them off.
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