What are the most common problems that owners have with the KTM 990 Super Duke R?

The KTM 990 Super Duke R is well known for its thrilling performance, as well as its character, but as with any motorcycle, it has its own quirks and potential problems. There are many things that owners of this model have discussed over the years, mechanical and maintenance issues included. These can be minor annoyances or more serious concerns that need a lot of attention. Knowing what these common issues are can be very important for possible buyers or current owners who want to keep their bikes in good shape. Here is the question in question: What is the real world of 990 Super Duke R owners and the problems you have with your machines?