A few years ago I flew out with bike bags allowable to 32kg/oversize, on the way back, Canadian check-in said they had a lower limit than the internationally agreed 32kg. Perhaps the staff that load the departing planes are not as strong as those that unload the arriving ones?!
Anyway, they’d already sent our normal bags (with my penknife) into the maze of conveyor belts, so we were left standing at the desk with two bike bags over 30kg’s, unable to open them as I’d put a zip tie through the zips, and no bags to juggle with contents into.
We stood there for quite some time whilst supervisors etc confirmed that no, the limit was xxkg (30?). Being out of options, we stubbornly insisted and in the end the supervisor walked away and check in person just said take them to oversize.
So top tip, weigh your bike bags first so you still have the option to throw away your underwear/pet sitter presents and repack, rather than abandon your pedals 🙂
P.S This was Canadian Affair/Thomson desk. I don’t think they were trying it on, they were very insistent.