Low maintenance A2 supermotos?

Hey guys,

Since I'm getting my A2 license soon, I'm looking for a license to get then. I want a Sumo again. Since I ride a lot (almost 12,000 kilometers a year), it shouldn't be too maintenance-intensive. Whether I have to restrict it or not is irrelevant to me (I'm just as happy with a 450 as with a 700). What I mean by low-maintenance is that I don't want to have to change the oil every 10 hours of use. Whether it's 2- or 4-stroke isn't really important to me. It shouldn't be too expensive either. My budget would be a maximum of 5k for a used one.
thank you very much for your help

Kind regards, Ben