I changed my battery today, problem solved!
I called my mechanic today about the problem with my engine not starting up despite my battery being fully charged. He told me that there are almost never anything wrong with the starter on Kawasaki motorcycles so it had to be something wrong with the battery. I changed to a new YUASA YTX12-BS battery and the engine fired up just fine! You should have seen the smile on my face hearing the engine starting :)
The new battery, YUASA YTX12-BS, same type as the old one.
There’s a set of tools under the seat, you’ll need a standard screwdriver.
Remove the old battery (negative/minus side removed first) then insert the new battery (positive/plus side connected first).

