So it looks like the Tosa has been a great gateway drug. After 1/2 season on the tandem, Mollie, who was deathly afraid of road biking, now wants her own single! We're both really excited about this.
The interesting thing I noticed was this--Mollie has been complaining recently that the stoker compartment on the Tosa is too short, i.e. she doesn't have enough room to get low and into a more aggressive position for climbing/going hard on the flats. I had a really good experience with Flyte for my single, so we took her measurements and sized up a bike for her. As it turns out, the top tube on the Tosa is RIDICULOUSLY short for her if you look at her reach to the bar on her single. If we set up the reach to the bar on the Tosa the same as it would be on her single, the bar would be right about at my seatpost. That's a good 5-6 INCHES ahead of where it is right now. We hopped on the tandem and I placed a bar right at my seatpost, and she said the reach was quite comfy. I guess she has a long torso for a woman or something...
I did a quick search of the various tandem manufacturers, and Burley lists a stoker top tube length of 700mm regardless of size. Other manufacturers that list geometry on their web sites are about the same.
Are we stuck going custom if we want a fit for Mollie that's similar to her single? We probably want to hang on to a tandem for longer rides/centuries/etc., so we want to get the tandem comfier for her... any ideas?
DrPete
twilkins9076
04-16-06, 08:13 PM
We've noticed the same thing with our Burley Duet (new this spring), except we have the opposite experience. We're both small, and Pam finds the shorter reach on the Burley more comfortable than the Extra Small sized Specialized single that she's ridden for a few years, even though it was a good fit and she looked comfortable riding it.
When we were shopping for the tandem, our LBS pretty much told us that fit on a tandem was often a matter of compromise unless you were going the custom build route. I think I recall that the smaller stoker cockpit was a matter of what was necessary to minimize frame flex and provide strength to the longer frames. Somebody out there probably has a better (and possibly more accurate) explanation, but my point is that we knew going into the process that the stokers top tube was going to be shorter.
TandemGeek
04-16-06, 08:25 PM
Are we stuck going custom if we want a fit for Mollie that's similar to her single? We probably want to hang on to a tandem for longer rides/centuries/etc., so we want to get the tandem comfier for her... any ideas?
It depends on how much more room she needs.
Here are the longer stock tandems:
Rodriguez @ 30" on all sizes
Trek @ 28.7, 28.5, and 28.8 on S, M & L
Co-Motion @ 28.5 on all sizes
Cannodale's XL/M @ 28.1" & Jumbo/L @ 29.1" (M/S, L/S & X/M sizes are 27.1")
If you need something longer, one of the best values in a custom tandem is a Bushnell ($175 upcharge). Co-Motion also does custom geometry for a stated upcharge of $375, but you can sometimes catch them offering either custom sizing or custom paint for no upcharge when production begins to fall off after all of their dealer pre-sales are delivered.
As for customs, you can also get into a really nice Erickson for not much more than some production models when you compare apples to apples on cost. However, having mentioned Erickson, let me now talk a little bit more about Rodriguez tandems, sold through R&E Cycles in Seattle, WA.
I'm sure it caught your eye that Rodriguez tandems are built with a 76cm (30") stoker compartment for all three of its stock sizes of tandems (S, M & L). R&E cycles (www.rodcycle.com), was founded by Angel Rodriguez (R) and Glenn Erickson (E) back in the 70's. Glenn Erickson was the guy behind the Rodriguez tandem designs from '77 - '87 and early-on realized that stokers who were accomplished road cyclists really got "short-changed" on riding position. To remedy this, he gave all of Rodriguez tandems a longer rear stoker compartment (29.5" - 32") and beefed-up the tubing designs to mitigate the added torsion loads on his longer frames. Rodriguez and Erickson decided to sell their business and go their own ways and since '89 Erickson has designed, built & delivered about 500 one-off custom tandems bearing his own name that feature very aggressive geometry and very long stoker compartments that cater to more experienced teams who understand the value gained from retaining their individual single bike riding positions on tandems. We have two Erickson tandems and, even though Debbie is only 5'2", she enjoys every inch of her 31" stoker compartments. Now, here's the really cool part... while Erickson designs and does all the detailed frame finishing on his tandems, Dennis Bushnell has been his frame fabricator since he started building under his own name. Guess who else Dennis builds for besides himself? How about Rodriguez? And that's why the three Seattle-based brands of tandems all tend to share similar design traits: they all have an Erickson design pedigree.
Bottom Line: If you want top shelf in terms of custom fit, performance and finish, you go with Erickson (they're all custom one-offs). If you want off-the shelf production quality with 30" stoker compartment, you go with Rodriquez. If you want a best-value custom, you go with Bushnell. You can upgrade and option both the Rodriquez and Bushnell to tweak the geometry, add fillet-brazing, or to go with a high-end paint job.
More than you wanted to know....
TandemGeek
04-16-06, 08:54 PM
I think I recall that the smaller stoker cockpit was a matter of what was necessary to minimize frame flex and provide strength to the longer frames.
Early tandems had very short (24" - 25") stoker compartments. Over time, better designs, stiffer tubing, and consumer demand have caused builders to figure out how to offer longer stoker compartments. The longer tandems can sometimes put a higher task load on the captain and work best with stokers who have a smooth pedal stroke and good form. For many teams, the longer tandems are a blessing that leaves stoker's smiling. But, for many other teams, the 27" - 28" stoker compartments remain the best choice, e.g., first time teams, tourists who don't need stretched out riding positions, stokers who prefer to ride more upright, and any team that stuggles with "stoker-steering" or "weight steering" issues.
I'm sure 'Zona' will weigh in here regarding his and Kay's AriZona tandem which sports a 24" stoker compartment, noting that Kay is a bit under 5' tall.
Again, this is why I always suggest that first time tandem buyers look at their initial tandem purchase as just that: their "first" tandem. While some teams find they are content with their first tandems, many others learn what it is they like and don't like about their first tandem and then apply what they learn when they buy their next tandem to get it "tailored" to better meet their needs and preferences. And, over time, some teams may find that their needs and preferences will continue to evolve. On the bright side, a long tandem can always be fitted with a longer stoker boom to shorten up the reach... which is a lot easier (and better) than trying to make a tandem that's too short longer by shoving the stoker's saddle backwards (and screwing up their saddle set-back / pedal stroke) or putting the handlebars under the captain's saddle -- and the stoker's nose in the middle of the captain's back.
DrPete
04-17-06, 03:50 AM
TG--Thanks for all the info, as usual. We were discussing the issue of the "first" tandem, and we did arrive at the conclusion that we had no way of knowing that Mollie would want to have a long top tube to ride aggressively. When we bought the Burley, she liked the short tob tube because the bike felt more stable and safer to her. And you're right--she may have hated it and this would all be a moot point. We're definitely happy that she's enjoying riding so much and wants to ride harder!
There may be a nice '05 Tosa for sale pretty soon--we'll see how the fit of her single suits her after a few hundred miles and make the decision from there...
DrPete
dubbelop
04-17-06, 06:43 AM
Early tandems had very short (24" - 25") stoker compartments. Over time, better designs, stiffer tubing, and consumer demand (fed by builders like Erickson) have caused builders to figure out how to offer longer stoker compartments.
Once we asked the late George Longstaff (an English builder of first class bikes, trikes, tandems and tandem trikes) why his stoker compartments were so short in comparison to Burley or Cannondale. The historic answer was: "Because Reynolds will not supply longer tubes!" :rolleyes:
Leisesturm
04-17-06, 02:31 PM
I did some very unscientific casual bike fit comparisons between our two tandems this weekend. This was before I saw this thread but my observations may have relevance. The Raleigh Coupe is advertised as a hybrid between the offroad oriented Companion and the Race ready Prestige tandem's. Our Kent tandem is very much like the Raleigh Companion in dimensions and orientation. Both have upright handlebars the Kent with 3"+ of rise the Coupe with none. I modified the Coupe at the time of purchase with some 35mm rise bars. Doing an elbow to fingertip measurement on the Kent captain compartment sees my fingers reaching the far side of the bars and a little. The stokers compartment is much smaller. The difference however is just about the length of captain stem extending out over the front wheel. In other words the effective captain top tube and stoker top tube are the same. If you figure that 6" of negative reach is supplied by the stoker stem then the actual stoker top tube length is actually longer than the captain top tube. On the Coupe my fingers do not reach the bars, wanting at least another 2" to do so. The rear compartment is proportionately smaller. In the Coupe case, however, the stoker stem is adjustable and is currently at full extension, i.e. there is room to enlarge the stoker compartment if need be. My GF is not short for a woman, about 5'6". She definitely is the long torso type. I have seen some pictures of track tandems in action and compared to them, mentally, the stoker compartments of road tandems are spacious to a fault. It seems to me that IF a larger stoker compartment is needed a very good way of doing it without resorting to the considerable expense of a custom frame would be to reverse the stoker stem so it put the bars ahead of the captain seat post. I see the TandemGeek already sussed this (why am I not surprised) however, I think this would bring the average female stokers face possibly 6" - 8" closer to the captains neck. Unlike TG I don't think most stokers are so short as to be looking into the captains back. I do agree with all his other points. Given that most tandems seem to have the stokers face a good 16"+ back it does not seem an unreasonable modification for the probably rare couple that need it. I think a closer coupling of captain/stoker would actually reduce weight steer as such forces would have a shorter moment arm on which to act. Verbal communication between captain/stoker would be increased. There may be problems to reversing stoker stems and I can't say I have thoroughly worked out the idea as there is no need for such a modification in my own situation. It seemed worth throwing out there though. I've read TandemGeeks post again and I agree even more with his observations but stop short of endorsing encouragement to give stokers more space. I honestly think that tandems are about as long now as is practical. Ours barely fit into a subway car. If the main idea behind a tandem is to have two riders with the frontal area of a single rider then design IMO should focus on getting the stoker closer to the captain rather than vice versa. If there were no aerodynamic penalty to moving stokers rearward racing tandems would not have such extremely small stoker cabins. At what point does the comfort of the stoker make having a tandem moot? For us the question really is moot because Julie cannot ride on her own but I think it is valid in terms of this discussion.
H
DrPete
04-17-06, 05:20 PM
While I see your point about the advantages of placing the stoker closer to the captain, I'm guessing that you're writing from the standpoint of a captain who doesn't have to worry about his knees hitting the bars when he stands, or having his face stuck into someone's back in order to ride in an optimal position. Placing the bar under my seat only accentuates this.
It's unfortunate, but I think another issue at play is that the majority of mass-market tandems (if there is such a thing) are geared toward a team of an experienced captain who would favor a lower, longer position, and a less-experienced/fit stoker who gets the more upright position and is forced to compromise.
DrPete
TandemGeek
04-17-06, 08:31 PM
I have seen some pictures of track tandems in action and compared to them, mentally, the stoker compartments of road tandems are spacious to a fault.
A track tandem is a very different animal from a road tandem, far more so than even a track bike compared to a road bike: short, stiff, and purpose built for massive sprinting efforts that last minutes on a circular, banked track.
Similarly, time trial tandems can be incredibly long to allow both riders to assume a full-on aero position for full-on efforts on relatively straight, non-technical roads that last less than an hour.
An all purpose road tandem is, therefore, not comparable to either since it must work well for a wide range of uses and riders.
I see the TandemGeek already sussed this (why am I not surprised)
Not exactly. The point I was making was that with the exception of speed event-specific tandems, it is impractical to assume that a stoker's handlebars should fall under the saddle of the captain for variety of ergonomic (and aesthetic) reasons.
As an aside, if you haven't spent much time as a stoker let me suggest that you find a way to do so. Stoking is an eye-opening and humbling experience (Note: Everyone who captains should immediately find their stoker and convey to them in an appropriate manner your most sincere appreciation and thanks to them for indulging you in your love of cycling).
I think a closer coupling of captain/stoker would actually reduce weight steer as such forces would have a shorter moment arm on which to act. Verbal communication between captain/stoker would be increased. I honestly think that tandems are about as long now as is practical. If the main idea behind a tandem is to have two riders with the frontal area of a single rider then design IMO should focus on getting the stoker closer to the captain rather than vice versa. If there were no aerodynamic penalty to moving stokers rearward racing tandems would not have such extremely small stoker cabins.
Please don't take this the wrong way, but this reads like a Santana catalog. I'm not being mean spirited and, to your point and to Santana's philosophy on tandem sizing, fully 90% of the folks who buy tandems will adapt to the fit of any production tandem. After all, the average tandem consumer is not looking to do 4 hour centuries and will not spend their weekends banging elbows with the racer boys on high-tempo club rides, never mind doing a tandem stage race. However, for experienced couples who have very refined riding positions or any other serious cyclist/athlete who intends to spend lots of time hammering away on a tandem, or jumping back and forth from a single bike to the tandem, a longer stoker compartment that will allow the stoker to replicate their single bike riding position becomes a welcome feature. And, yes, there can be some trade-offs on handling with long wheelbase tandems; however, longer wheelbase tandems also tend to be built to be very stiff, sometimes trading off a bit of comfort for additional performance and road feel. In fact, while it may seem counter-intuitive, some of the longest tandems also have the most aggressive steering geometry. And, to the credit of builders like Erickson and Co-Motion who have built their reputation on catering to teams looking for a more performance-tuned feel, Burley and Trek have both added "Race" oriented steering geometry to their line-ups over the past two years.
This all brings us back to Dr. Pete and Mollie who typify many of the tandem teams that make up that 5% - 10% of the market that have the interest, resources, and desire to "investigate" the possibility of finding a more tailored fit for their long-term tandem. It could be that just the extra 1" offered by a Co-Motion would be enough or perhaps that extra 2.5" offered by Rodriguez, a custom Bushnell, or a creme-de-la-creme Erickson will be their "dream machine".
Bottom Line: Consumers drive the bicycle and tandem market and what sells the most is what gets produced in the greatest volume. Therefore, finding the right tandem is not always as easy as it might seem and what's best for one team will not always be the best for the next team that comes along. The trick to long-term tandem bliss is finding the best tandem for you and yours.
Here's hoping everyone finds a tandem that makes them want to ride... regardless of their reasons and goals for riding.
zonatandem
04-18-06, 12:05 AM
Just like a pair of shoes . . . if none fit properly, get 'em custom made!
Seeing this is not your first-ever tandem, sounds like you'd better look into a custom twicer!
If you really enjoy riding TWOgether, it is a very worthwhile investment!
As Mark said, we run a super-short stoker compartment for Kay who is a 'tall' 4 ft. 10 3/4 inches!
Make your stoker H*A*P*P*Y*!
Pedal on TWOgether!
Rudy and Kay/zonatandem
tornadobass
04-18-06, 12:05 PM
We have a Rumba Softride...how does that design fit into the overall stoker compartment discussion? For example, it's possibe to position the seat over quite a range along the beam. And then the tall-person bracket offers a bit more setback.
Do we get more space or just more space with an odd offset from the cranks?
TandemGeek
04-18-06, 01:06 PM
We have a Rumba Softride...
...just more space with a potentially odd offset from the cranks.