Hi, I own a 2018 ktm rc390 and it’s been 5 years since I’ve got this bike. Recently I’ve noticed that the handling is off. As in I don’t feel the confidence. Few years ago I changed my tyres to apollo alpha h1 from metzeller sportec m5. Few months ago I changed my rear suspension from endurance to wp. It’s a bit stiffer but was no issue. Few months everything was ok then last week or so I feel off about the grip. The tyres are close to the end of their life but I’d say they have a few 1000 km left. Also the moment I go above 140 I can feel some oscillation on the handle bar. The way I can best explain this is like it feels like the bike is squatting.”like the rear is lower than the front or something. But visually its rear is higher. Note that I’m referring to the seat. Like it feels like it’s declining but it’s still inclined. Any idea what I need to look into ?