Weird Whining Noise while running

Hey guys new to the forum and just bought my first quad, its a 05 400 ex. I bought it from a guy who said the whining noise is the starter clutch that doesn’t work anymore. Currently the electric start doesn’t work but it’ll bump start no problem. Heres a link to the video i posted up on youtube. Im curious to see what you guys thing before tearing it down, any help is greatly appreciated!!

https://youtu.be/0vyM3gJuB18

Trevor