There is no separate transistor on a Kawasaki ninja. They are inside sealed units. Either a silver/grey box or black box.
Anyway, a million reasons for any motorcycle not starting.
Always start with : Is there spark?. Is there fuel?.
Please look up the service manual or Haynes manual for your bike.
You didn’t even share with us which bike it is or what problem the bike has. You said nijah twice. It’s NINJA.
Martin