AMuzi wrote:

Which is superior and good engineering for
that overly torqued inner ring hardware.

What is the superior way to keep the chain
straight on tandem bikes?

I once saw a small chainwheel, slightly bigger
than an RD pulley wheel, in a vertical track,
so it could be adjusted up/down to interfere
with the chain.

This made sense to me, maybe because
I understood it, but I have since then seen
modern tandems and they don't have it.

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