I wouldn't consider a CR80 a "mini". Hell, the Big Wheel version isn't much smaller than a 125 MXer.
50's and 65's are mini's. 80's are in-betweeners.
They are designed for kids. I'd think anyone over 150lbs would want a bigger bike.
That said, don't underestimate it. Once on the pipe, that "kids bike" won't hesitate to put you on your ass.
I have no idea on parts interchangeability.
