02-0307S  Starter coupling with screw(6mm inside dia) (Early 3D/Sport, Converted Pro model)

 

Note: On early Pro kits a 5mm Id was used on the starter shaft area, then stepped up to 6mm for the oneway bearing.

          after a update on later Pro kits went to a straight 6mm shaft with an E clip, this continued on to be used in the

          sport kits and early 3D models.

 

          It is advised to update a older 5mm stepped starter shaft, to the later 6mm 02-0317S,

          this will intail changing most of the starter area but in the long term the best solution.