Love,

You have some learnin' to do about tandems if you believe that the inclusion of an Arai drum brake necessarily means the bike is old. An Arai drag brake is the standard for scrubbing speed from a tandem on mountain descents or hilly areas. While Arai no longer makes the Arai drag brake, no other available product has emerged to replace it. A decent condition Arai drum brake has been selling for over $200 on eBay recently.

Cannondale hasn't really changed their tandem frames all that much, and have never really needed to. Cannondale tandems typically have a much longer stoker cockpit than other bikes allowing to fit a wider variety of stoker body types than many other non-custom makers.

I have a Cannondale tandem and think they are incomparable until you get into the world of Calfee carbon tandems, Co-Motion custom Aluminum tandems, Paketa magnesium tandems etc. That Cannondale will outperform any steel tandem, that's for sure (riders being equal). I've always felt that a Cannondale tandem purchased off Craigslist is the best value in tandems period.

The critical thing for fitting a stoker to a tandem is making sure you have enough available "extension" to fit a parallelogram suspension seatpost for your stoker. This is typically a problem with short stokers on frames where they aren't showing a lot of seatpost.

Parallelogram suspension posts that come to mind:

Tamer Pivot Plus
Cane Creek Thudbuster ST
SR Suntour makes some cheapie versions as well

My preference is the Can Creek Thudbuster ST, for a stoker on a road tandem anyway. I've talked to Ryan McFarland the inventor of the post, and he's a first class guy who really thought through the design.

I didn't catch that you listed the size of the Cannondale tandem, however Cannondale tandem sizing is the same as the old Cannondale ST series touring bikes. They are measured in inches, along the seat tube, from the center of the BB bolt up to the top tube. The largest size was a Jumbo/Large which would be a 25" captain's and a 23" stoker's. Jumbo was also offered in a 23"x21" called Jumbo/Medium. From there all kinds of sizes were offered.

Fit on a tandem is critical. Much more so than on a single. You can not conveniently get out of the saddle to give yourself a seat area break in the same way you can on a single. Before dropping a grand on a tandem I would invite an expert in bike fit to help you. That does not mean what it sounds like. It definitively does NOT mean to solicit the opinion of any hipster wrench down at the LBS. Most bike shops have a deserved reputation of pushing people out of the sport of cycling, more so than bringing them in. The average road bike is sized to fit cyclists to the hoods, not the drops, for a case in point. Find someone who knows what they are talking about, not just talks about fit.

For a starting point try these two links (single bike context, but the gist is the same):

http://www.peterwhitecycles.com/fitting.htm

http://www.rivbike.com/article/bike_...izing_position

I think you'll find that by the time you consider the "stack height" of the suspension post the C'dale will be closer to fitting than you might think. However, if the stoker compartment is a Small you might be better off looking for a different bike.