i never prime, try kick start it or pull start it whatever u got, Wack it on choke, kickstart it twice then put it on open or RUN and kickstart it again, it should start 3rd time if u do this. If not then kickstart it again on RUN. Then pump the throttle for about 1 min, then stop it and then actually ride. On a Cold night ( dont ride in morning coz of school ) when its about 10 degrees i do this then the motor is nice and hot and then when u actually start it it will kick over easily, i got no clutch so i cant kick start it then put my bike on the ground, i kick it get it all nice and hot then roll start it.
Hope that helps a lil, the choke sorta works as a primer but i find it works better.