not travelled with the bike for a while now, but different airlines have their own rules/guidelines for the max. weight limit – last time i did the group of riders in the queue at Liverpool Airport did this – everything was in their bike bags (tools, body armour, camelbaks, spares etc.) and they had to pay big time with weight penalties
they had to step out of the line and totally repack their kit (putting body armour in their main luggage) to minimise the extra charges (still had to pay something like £100 each)
with bad luck we ended up getting the very same check-in attendent but she was fine with the two of our bikes even when they were slightly over – turned out the other group had entire tool boxes in their backs, one bag had six extra dh tyres in and were doing the old trick ‘lifting the bike bags off the scales’ during weigh in