Part for sale is: Battery eliminator Stator Magneto set.

This part fits 1969 & 1970 CT90 (trail 90) 

This set is used and in great condition. 

You will have to have a professional install this. I am not sure how to hook up the wires. This set was designed to eliminate the battery completely. 

Do not buy this if you are unable to take the time and figure out how to hook it up properly.

The idea of this set is that it creates enough power to run your electrical all at once. I am not sure if you need to use a voltage regulator with it.