This article is from the Sea Kayaking FAQ, by Todd Leigh with numerous contributions by others.
Under the piece rule, someone traveling alone with a single kayak or
two people traveling together with a double kayak (and pooling their
total free allotment of four 70-pound bags) might just be able to come
within the free baggage limits, particularly if the airline allows one
or more of the bags to be oversize and/or overweight under a special
rule for sporting equipment.
Under the weight limit, even the most spartan kayaker or pair is
almost certain to be over the free baggage limit unless the airline
makes some special exception for their sort of gear.
It's thus crucial to figure out in advance whether any flights you
might take outside North America will all be included in a through
fare to or from North America. If they are ticketed separately, or at
a separate fare, they will be subject to the weight rule.
Per-kilogram excess baggage charges on a 70-pound kayak bag for even a
short flight ticketed separately within Europe or another part of the
world could be surprisingly high.
 
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