Hi,
Try to rent, borrow or test ride a quality touring tandem from someone who understands tandemming. My wife and I have been riding tandems for many years. We started with a wippy Gitane. This was a test of our relationship. It rode rough, handled poorly and the brakes were boarder line, but we endured and put a lot of miles on it. We moved up to a mid-level Santana. Although a bit stiff, it was a great improvement. A suspension seat post for the stroker is a necessity. A few years later we added a MTB tandem, which we still have. It's more comfortable and more stable than the Santana, but not as efficient. It's been equipped with suspension seat posts and a suspension stem. Overall it's a good ride for a couple of seniors.
It's convenient that you're going to start in a flat area, because tandems are tough on hills. Also, as a captain, you must communicate with the stroker when you, brake, coast or pedal or you are going to have a very upset stroker.
Good luck and give it a try!
Cheers,
Van
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