Its a auto Choke system in NTORQ, connected to the carburettor. Rider doesnt have to do anything manually, except starting the vehicle after a long break, allow the Autochoke to help the engine ...
"California’s attempt to effectively abolish the internal combustion engine by forcing Americans ... Barr said the regulations would put a “choke hold” on the state’s economy.
In Platina 100 ES the choke will be near to the carburetor on the Right hand side, under the petrol tank.