after starting..bike wants to take off without throttling and it wont let you shift out of gear until you shut it off..

[2015 Z Force 800 53/Trail EPS]

That one needs to go in for sure. It's idle may be way too high probably because of a control problem like a faulty idle-air control valve or just a bad one-way bearing.

It may be the overriding clutch bearing that will also cause it to do that.