Bike + suitcase is 18kg.

I checked the amount of room above the seat tube - there's not enough to leave the seat post + saddle in. If there's time tonight I might revisit the packing and tape the seat tube, handlepost and the front wheel in place, so that the whole can be lifted out.

The case is pretty full - definitely no room for my helmet. I might be able to tuck my cycling sandals in somewhere, plus gloves, socks, chain lube.