Listen to what they’re saying on and off the bike and be sensitive to how they feel on the tandem as you push the envelope or engage in any other “technical” riding situations.
It’s pretty easy to “hear” your stoker say, “slow down” and by all means, if they tell you to “slow down” or “back off” then do it. Riding in a pack or side-by-side with other bikes and tandems can also be a source of anxiety, never mind getting into a full blown sprint with a group of bikes and tandems. Some stokers may be reluctant to say anything on the bike while you’re riding, but will share their anxiety with you and/or other stokers off the bike, e.g., “I was really scared, uncomfortable, closed-my-eyes, etc…”. Again, be attentive to those comments, even if they’re made to others.
In addition to on-bike and off-bike comments, you should also learn to “read” your stoker’s comfort level through their “body language” on the bike. If you’ve become comfortable as a team on the tandem, then you should now be able to feel your stoker tensing-up and turning into dead weight instead of a riding partner. When that happens that’s a bad thing because it means your stoker is no longer working with you and their stiffened-posture on the back of the tandem will adversely affect how it handles and responds to your steering inputs. Again, if your stoker goes rigid or becomes tense, it’s time to back-off, increase your spacing, move away from the edge of the road, etc.
It’s been my experience that if you are attentive to your stoker’s comments, how they “feel” on the bike and encourage them to be candid about why they became uncomfortable, you’ll be better off in the long run regardless of whether it opens up the performance envelope or defines the edge. More specifically, after hitting the edge of their comfort zone talk to them and find out if, in retrospect, they now feel like they “pushed through” a threshold for speed, pack riding, etc, or if they think they’ve found their limit. Talk about their concerns, bearing in mind that this is all really about mutual trust: trust in your judgement and skills and your trust in their ability to be honest and candid with you. I’ll be honest, I used to take humbrage when Debbie told me to slow down or “don’t ride so close to them” because I took it to mean “you don’t trust me”. After riding on the back of a tandem, I gained a whole new perspective on what a stoker experiences and have a greater appreciation for the huge “leap of faith” it requires from a stoker when you push a tandem through technical descents, along the edge of a road, or in a pack of bikes.
BTW, if you think a stoker can become nervous on a road tandem being ridden on paved roads, consider how they feel when you take them onto technical single track on an off-road tandem where downhill speeds can still push into the 20’s & 30’s while flying over rock fields, roots and getting slapped in the helmet by tree branches. Debbie has been a trooper on both our road and off-road tandems, allowing me to peg our top road speed at 63 mph in the Talladega Nat’l Park many years back, and regularly putting up with 50+ MPH descents. A lot of that on-road trust has come from our off-road tandem riding, where the risks of serious injury can be just about as high as they are on the road, noting we’ve had more fall-offs off-road riding than I can recount. But, the key was always talking about what we were doing before, during and after to make sure I knew if I’d hit or crossed any thresholds.
And, just because it’s OK to bomb a twisty descent at 50 mph one day doesn’t mean it will be OK the next: call it a woman’s perrogative, if you will. Moreover, you may find after several years of riding together that your stoker’s performance envelope threshold will begin to shrink and instead of hearing “slow down” at 55 mph, you may hear it at 45 mph. As we’ve gone from our 30’s into our 40’s and now find ourselves comfortably in our 50’s, Debbie’s enthusiasm for fast mountain descents has waned a bit. Instead of being heads-down / tails-up, we’ll simply do those descents sitting up to keep our speed in check… most of the time.
Bottom Line: With very few exceptions, most of us aren’t out there racing for national titles so there’s no real reason to “push” you, your stoker and your tandem to the edge of the envelope where the risks outweigh the rewards beyond a cheap thrill or bragging rights that are typically pretty shallow and short-lived anyway. Treat your stoker like an equal partner in your riding decisions and habits and see where it takes you. It’s all about trust and trust comes with open communication, not assumptions.
Oh yeah, mutual trust in your equipment is also a must. If you plan on pushing the envelope pre- and post-ride bike tire/wheel/brake checks are a must as are fresh brake pads every other year (minimum). I also inspect our fork, handlebars, stems and seatposts on a monthly basis and always have. Any new noises require quick diagnosis and resolution. My attention to our equipment merely reinforces Debbie’s trust in me. Did I mention that it’s all about trust?