I got 04 mini cooper s with 120k. I noticed that especially when car is warmed up, rpm suddenly goes up to 4000-4300 while I was running in 4th or 5th gear. I was running around 3500 rpm and accelerating more and I didn't shift though. it comes back to normal but I have no idea what's wrong with it. I bought this car 2 months ago but haven't changed the transmission fluid. Is clutch slipping or is it low fluid level?

 

Clutch slip IMHO.

 

Yep, Sounds like classic clutch slip. 120k isn't too bad for a dual flywheel clutch. I'd put in a single, ECS sells them.