50cc big bore upgrade question  By  gyguy (Read 256 times)

Can anyone explain why you can only go up to 150cc big bore from a 50cc stock gy6?  How come I cant put a 180cc big bore kit on the 50cc motor?

Just wondering if i should buy a scooter w/ a 50cc that is $500 less than the 150cc version and then put a big bore kit on it.


Any and all input is welcome and encouraged!