By Train:
You can book a train ticket till Kodaikanal Road Railway station (KQN) from Bangalore City Railway station (SBC) or Cantonment (BNC) or Carmelaram (CRLM) or Hosur (HSRA).
Book your rental bike at https://rento.bike
Get down at Kodaikanal Railway station, just come out and find rentobike office opposite to you. Pick your bike and continue your kodaikanal journey.
Within 2 hrs your will reach kodaikanal with your own freedom.