I brought my 1938 600cc engine over to England with Norwegian Air Lines some 3 years ago for an overhaul by Roger. The crankcase with pistons and rods & all accessories packed into a light suicase weighed ca. 31 kilos. The cylinder block weighed 9 kilos, and I managed to convince the airport security to accept it as cabin luggage. It was thoroughly cleaned before departure to avoid oily smells.