The 2024 KTM 990 Duke 96% new and replaces the 890 Duke R. We tested it in the mountains of southern Spain as part of KTM’s “30 Years of Duke” launch that included the 390 Duke and 1390 Super Duke R Evo. (Photos by Francesc Montero & Sebas Romero)

What?s the magic number" When the first Duke debuted 30 years ago, it was 602cc, which was packed into a single-cylinder engine that made 58 hp. These days (in the U.S. market), Dukes range in displacement from 249cc in the Duke 250 to 1,350cc in the 1390 Super Duke R Evo. In between, KTM offers the 390 Duke (399cc), 790 Duke (799cc), and 990 Duke (947cc). For this KTM 990 Duke review, we take one of the newest Dukes on a test ride in the mountains of southern Spain.

Related: 2024 KTM 390 Duke Review | First Ride
Evolution of the Duke. Front and center is the 1994 KTM 620 Duke. Behind it to the left is the 990 Duke, in the middle is the 1390 Super Duke R Evo, and behind it to the right is the 390 Duke. They are surrounded by other milestone Duke models from the past 30 years.

With its displacement approaching a liter, the new 990 Duke resides in the so-called ?super middleweight? class. It replaces the 890 Duke R, but there?s more to it than just a 58cc bump in engine size. According to KTM reps at the global launch in Spain, the 990 Duke is 96% new and ?more like a smaller Super Duke.?

Powering the 990 Duke is KTM?s liquid-cooled LC8c parallel-Twin with DOHC and 4 valves per cylinder ? th...