The keyway is for more gears that is why it is called a cone gear shaft. those gears are slid on from the left side of the shaft and held tight with a snap ring . hence the snap ring grove on the left side of the shaft. if you understand how a quick change gear box works you know what the reason for the cone gears are.
That said, there is no way to cut the keyway as is with the gear in place. More than likely, the gear was pressed on after the keyway was cut. From a manufacturing standpoint, it also makes more sense to make the part as an assembly rather than a single piece.
I agree but I tried to press it off and would not budge so I went back to the Assy drawing and it is listed as one part. I respect your opinion, but it is one piece. Makes little sense to me also except it is forced marketing. If you look closely you will see they cut the keyway with an end mill and not the normal key cutter. In 1979 Harley Davidson (AMF) made their generator with the gear cut on the end of the armature shaft. Soft steel and the teeth stripped out. I was forced to buy the entire Generator from Harley Davidson. Sucks but call it extortion by planned design failure.
My thoughts were the same and I almost used heat and a hydraulic press to try to remove the gear. Caution told me to look at the print and I decided it must be one piece. Really wish my Microscope would work so I could get a picture of it but for some reason it refuses to work now. I have one called Max-See. and for some reason the software just took a crap.
I did the same thing today with my camera on my phone. You can definitely see that first they cut the key-way with a rotary horizontal cutter then finished the last .500 with an end mill. Who knows why.
