ATK 406 info?

Hello all, I am new here and seeking wisdom on a ATK 406. I have found various posts of people asking info on this motorcycle, some very old and some more recent. I have the opportunity to acquire an ATK 406, and while I have read great things around the internet, it is an old motorcycle, so i want to make sure that I am not digging myself into a hole.
Below is a picture of the bike, through my research, i've found that it is an '89? if anyone can confirm this? It is not ran very often and sits most of the time (it is in running condition though). The only info I currently have on it is that there is something wrong with the clutch and the front brake is not working. I read online that if it sits for a while, the clutch plates often stick (not sure if proper terminology?) and so the solution can be as simple as separating the plates? If a whole replacement clutch kit is needed, is this something that is impossible to acquire simply due to its age? I've found some websites that offer parts but i dont know if perhaps the websites are just out of date. Other info I have is that the motor has been rebuilt and the carb was jetted at the same time (again, not sure if proper terminology?). Current owner is a trusted person, just currently out of contact. Just looking for additional info on this particular model if anyone has any experience with it.
Thank you!
Welcome to DBA Reynaldo.....this is mainly a welcome as I have no experience with those bikes, however I have seen discusion on ATK's here somewhere, I looked but couldn't find the thread(s).....but it think there a couple members that may be able to help.
American bike with a Rotax motor, Rotax made motors for bikes, ultra light aircraft, snow mobiles etc. So parts shouldn't be too hard to acquire. The body work and mechanical parts might be hard to find.....
I was thinking back in the day of buying one of them, they looked like my 84 cr-500r, air cooled, which sounds sweet, and I bet it could throw some monster rooster tails, but the company went away, and I found a couple of vintage cr's and they are still here with me now, no room in the garage for em'....