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Yeah, I know the feeling. I feel like there's a lot more resistance in general, if we are coasting through a flat section the tandem doesn't even come close to keeping its speed like a solo would. I know using Marathons like I do on the tandem doesn't help, but I do wonder if there's not more to it than just rolling resistance.
To talk about the good bits: long stretches of gentle undulation are a blast, we find our tempo and feels like we can keep pedaling forever, the bike roaring along nicely.
All the rest is a bit of a slog, specially loaded. I'm using STI's which do help a lot with gearing but I get why people favour Rohloff on tandems. Chain tension is insane when climbing, downshifting can be a bit scary.
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Shouldn't being massively heavy mean that we keep this speed for longer? Pretty sure this is GCSE-level physics that I've forgotten. Who is stealing our speed?
Weight has nothing really to do with it.
Kinetic energy gets converted into gravitational potential energy. If it were perfectly efficient then:-
(We'll ignore the rotational energy of the wheels...)
1/2 * m * v * v = m * g * h
(g = gravitational constant of 9.8m/s^2)
The mass on each side cancels out and you're left with:-
h = 1/2 * v * v / g
So if you're in a vacuum and no rolling resistance then it doesn't matter if you're on a bike, skateboard, tandem or whatever.
But the KE to GPE transfer isn't perfectly efficient, the tandem will have a higher rolling resistance and higher drag coefficient. That's why you don't go as far up the hill as you do on a solo bike.
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ough
Greenbank
@Diamond_Supercool
Good to know that mine are common complaints. The flip-side, of course, is that on a decent bit of flat, it basically feels like we're floating because it's so easy to keep this "bike the size of a sofa" moving.
But what I don't understand is why, on rolling terrain, we lose speed so quickly when starting a little climb after a long descent? On an individual bike, I'd basically use speed gained on the descent to give me a head-start on the hill; on the tandem this speed seems to evaporate into thin air.
Shouldn't being massively heavy mean that we keep this speed for longer? Pretty sure this is GCSE-level physics that I've forgotten. Who is stealing our speed?