new guy/lots of questions

[ivan]

sup dudes, names ivan. i recently just bought a taotao bws for myself and a ssr metro for my girlfriend.

i got some questions about the engines. tao tao has a 150cc gy6? 157qmj? and the Metro says it has a 150cc engine but its a 152qmi?? thats a 125cc model? are they all just different sizes of the base gy6 engine? did i get that right???

other than that - what kinda plug would you run of each of those engines? (i dunno if they need to be different, heard some people use NGK CR7), and what weight gear oil?

any other knowledge you guys can drop on me would be great. i pretty much dont know anything about these. i just wanted one to put around town on nice days.

thanks