Originally Posted by Nanuq
If she has ample time on the 100cc, she should be fine on the 650cc, she will need to get used to it, but with a little time and effort she will be fine. Anything I can do on a 650cc, I learned on a 150cc. Some other questions to consider might be age-is her brain fully developed, particularly her front lobes, the decision making part of the brain? In essence is she going to be responsible enough to make quick decisions with a larger machine in a sketchy traffic or terrain. Secondly, how are her athletic skills in general? If she is naturally athletic she will have no problem adapting her skills and body to a larger bike. These are questions I always ask with my students and with my own kids + family.
She is a national champion skydiver, so she is pretty good with the quick decisions and/or pressure. What she is still lacking is the muscle memory, and natural reactions. She is very good about respecting her limits.
I have just been riding my whole life so I don't have that open thought to know if a 70hp bike would be alot to someone just starting out(intimidating) or if its what im thinking small enough, smooth enough power to have when you want but not so much to scare you that you may touch it by accident.
Thanks for the input again