Is the sprocket hub supposed to slip on or is it pressed on?
Has anyone had this problem before?
The splines look OK to me but I'm not a mechanic.

The hub is brand new (with a wear ring). I tried pounding on it with a rubber mallet and heating it at 200 degrees for a while(which worked great for the bearing races on the carriage).

The local shop removed the old one. I took it in because the race was stuck on the axle.

Thanks for the help.