44mm headtube was for 1 1/8" integrated headset. The one-point-five (1.5, 1 1/2) standard that the lower end of a tapered steer tube uses is 49.6mm. There are adapter headsets like the Cane Creek Cane Creek 40 ZS44/EC44 that adapt the 44mm headtube for use with a tapered fork. It has an external lower cup (which will slightly raise your axle-to-crown) and an integrated, zero-stack upper. That is the type you need to look for.