"Winters Shinkle" typed:

The weight of a typical bicycle probably wouldn't be a problem. The
components of any bicycle are heavier than water, I think, but the overall
weight shouldn't be as bad as an additional human. That is, assuming that
the weight is reasonably distributed in the canoe.

Daniel

its own weight with just the ends showing above water. Put a
heavier-than-water bike in there and it might sink completely. Load
in some more heavy stuff (Coleman stove, frying pan, or whatever) and
you could be in real trouble if you capsize. Consequently, you need
to think seriously of lashing some floatation into the boat; even an
old inner tube will do, if it is lashed firmly into the hull belowe
the gunwhale line.


Daniel, *weight*, itself, is not the issue. It is a question of
specific gravity. A 200# human has barely lower specific gravity than
water, so would not sink a canoe at all (once the entire package found
its equilibrium, mostly underwater) whereas a bicycle, with a higher
specific gravity than water, would contribute toward sinking the
entire package completely.

IOW, if an otherwise empty boat were fully swamped, with a human still
sitting on the thwart, the boat (if the weight of the human were
balanced fore-and-aft) would sink to a depth of three feet or so,
while part of the human's head broke the surface, because the combined
buoyancy of the boat and the human. The boat and the human are both
(barely) lighter than water. But if the boat contained an object
heavier than water (heaver per cubic unit; i.e., of greater specific
gravity) that object might counteract the buoyancy of the boat, and
sink the combined package.