Hi JonasB,
Bigip has two types of CPU, Control Plane, and Data Plane, but the dashboard shows us the Average of all CPUs, the most important CPU is the Data Plane because it processes the user's traffic so if it goes more than 80% you probably have a problem, but in the case of Control Plane is normal to see spikes in 100% when graphic, or API process in your case are executed.
For example, if you provision AVR and activate some features the Control Plane CPU probably starts to see spikes 100% all the time, but you don´t have to worry about this behavior, in the case that the GUI starts to fail or the response of the GUI is longest, you probably have to change the time of the API to 1:30 minutes for example and adjust the time.
Hope it´s work.