The present disclosure includes J-Gate adaptor assemblies for motorcycle clutch levers and related systems and methods. In one illustrative embodiment, a bracket on a side of a motorcycle serves as fulcrum for a lever rod mounted thereon via a heim joint. A lower end of the rod is attached to a clutch control cable. The rod extends upwardly, through a guide member with a guide channel formed as elongated slot extending in a first direction to a bend portion that extends in another direction to a “rest portion.” The rod may be levered in one direction in the guide channel to engage the clutch and in the opposite direction to disengage it. The rod may be held in the “rest” portion of the channel to retain the clutch in a disengaged position. Conversion kits and methods of converting and adapting motorcycles for using these types of assemblies are also included.