The subway is Downtown on Super Power Island.
He is in the subway, inside the train
Speeding Spike is in the Subway at Downtown.
The next villain is Speeding Spike in the subway tunnel. (see related question)
Go right to the front of the train and click on the door. Then go up the stairs.
you have to try to catch his attention make him go to the wet floor and then he falls and you catch him
In the subway gate
The island after Super Power Island was Spy Island.
No, there is no "super strength" on super power island glad to help :D
There are no cheats in super power Island.
(1) It's right by where Sir Rebral is and you can find ratman in the bathrooms and if you mean't sewer it is in the subway and speeding spike is there.
Go as far as you can to your right in Super Power Island.
He is in the subway car in the business district downtown. Go down the stairs, and right, and enter the train. (see the related question)