2024 KTM 990 Duke – First Look

Forget what you think a middleweight bike should be – KTM doesn’t care. Apparently engine size, like age, is nothing but a number. Hence the new 990 Duke comes to us as an exciting head scratcher. Following in the footsteps of the 790 Duke, which quickly became the 890 before shrinking back to a 790, the all-new 990 Duke (not to be confused with the former 990 Super Duke of the early 2000s) is aimed squarely at brute-forcing its way to the top of the middleweight naked bike hierarchy… by blowing away what it means to even be a middleweight in the first place.

The Duke made sense as a 790, started to blur some lines as an 890, and has now inched itself even closer to heavyweight status with this 990 offering (but don’t worry, the 790 is still around). The fact that the styling and physical stature of the 990 Duke has purposely grown to more closely align with the 1290 (and upcoming 1390 – KTM’s other worst kept secret) Super Duke Further drives home the point. Whatever category you want to put the 990 in, we're excited to throw a leg over it someday. Let’s break it down.

Where else is there to start than at the engine? All new for 2024, the 947cc LC8c is nothing like the 999cc Super Duke engine. For starters, it's a parallel-Twin and not a V-Twin. It’s also a departure from the 890cc LC8c, too. The obvious difference is a larger bore and stroke, but you can also count a new piston, conrod, crankshaft, camshafts, valve springs, engine cases, and balancer shafts among the differences between 890 and 990. Further, the 990 gets a reworked cylinder head and valve cover. We’re told the two engines look completely different side by side. These changes amount to 123 horsepower and 76.0 lb-ft of torque (103 nm), says KTM.

Unlike Dukes of the past, there’s a new swingarm pivot where the frame extends down and goes outside the swingarm bolt. Previous versions were the opposite, with the frame coming down inside the swingarm. This revision gives more side and torsional stiffness. Also new is the pivot bolt itself, which is now forged, to add to the overall stiffness.

The subframe is a diecast aluminum piece with an integrated airbox and air intake under the seat – similar to the previous Dukes. This allows for fewer parts in the overall construction of the subframe yet still yielding a stronger piece overall compared to producing a complete trellis subframe.

As for the swingarm, it’s a gravity die-cast piece, whereas the previous one was built with high-pressure die-cast construction. The result is a 4.8-lb weight reduction. Overall stiffness is lower than before with the new swingarm, which helps absorb bumps while leaned over and gives the rider more feedback at lean, too.

Unsurprisingly, WP provides the suspension yet again with the 990 Duke. Up front is a fully adjustable 43mm Apex fork with open cartridges and 5.5 inches of travel. Compression and rebound damping take place in separate legs, and to make adjustments easier to understand, the amount of clicks in the adjustment range has been brought down dramatically to just five clicks on either leg.

A WP Apex shock is used in the rear with only preload and rebound adjustability, and like the fork, it too only has a five-click adjustment range. The shock gets a lighter, linear spring along with different valving internally to provide the responsiveness KTM were after with the new engine and chassis package.

There’s a forged aluminum triple clamp with 32mm offset. This combined with the aluminum steering stem works in tandem with the overall flex of the fork to give excellent rider feedback. To make things more adjustable for the rider, the triple clamps and handlebar clamps can be moved in four different positions to suit your preferences.

Stopping the 990 are a pair of 300mm rotors which appear to be the same used on the 790 and 890 Dukes before it, though KTM says the discs are lighter than before. The KTM-branded four-pot calipers also appear to be the same J.Juan pieces the 790 and 890 used, too. A radial master cylinder feeds the brake fluid in front (and though we can’t prove it, is probably also the same as before). As much as they look the same, at the very least, the front discs feature a new disc mount, saving 500g of weight on either side of the wheel. In the rear is a 240mm disc.

The 990 Duke rolls on a familiar set of wheels, as they’re similar to the ones found on the 1290 Super Duke R Evo, only slightly modified for use on a double-sided swingarm. Both are 17 inches obviously, with the front measuring the standard 3.5 inches across and the rear 5.5 inches. This means standard tire fitment is a 120/70 in front and 180/55 in the rear. Providing the OE tires is Bridgestone with its popular S22 rubber, suitable for riding in all kinds of weather conditions.

• Rain Mode: As the name suggests, Rain Mode is for slippery road conditions. It reduces maximum power, gives maximum traction control, and the smoothest throttle response. The system aims to keep the front wheel on the ground all the time.
• Street Mode: Street Mode gives you full power, default throttle control, and middle-of-the-road traction control settings for street riding. Also, limited front wheel lift is allowed.
• Sport Mode: Here you get full power, more direct throttle control, and traction control is more lenient, giving you slight wheelspin. Front wheel lift is freed up a little more for maximum acceleration.
• Performance Mode: Performance Mode is an optional mode that allows a certain level of customization, letting the rider choose traction control and throttle control settings. You can also turn anti-wheelie off, and now you have the option to select launch control for perfect starts. Oddly, cruise control is available in Performance Mode (wouldn’t it be better in Street or Sport?), with riders having full access to KTMconnect, too.
• Track Mode: Track Mode is another optional mode that allows the same level of customization as Performance Mode, but with a focus on track riding. Here you get two display settings on the TFT display, with a focus on lap times, or telemetry data. In Track Mode, only key information is displayed with secondary information discarded. Anti-wheelie can be switched off and Launch Control is available for the perfect start out of the grid, but cruise control and KTMconnect are disabled.
• Demo Mode: Demo Mode is a controversial feature that allows the rider to experience all optional software for up to 1,500 km (932 miles), free of charge. After that, the rider can then choose whether to purchase the optional software features or continue riding without them. All optional software features can be purchased and activated by a KTM dealer at any time. Demo mode can also be deactivated by the dealer.

Allow us to take a moment to quote the KTM literature regarding the 990’s side profile because it’s so absurd that it needs to be repeated in full:

“In side profile and at a standstill, the KTM 990 DUKE is designed to resemble an explosion in a freeze-frame, mimicking immense energy being released with devastating force. When in motion, the wedge-shaped spoiler is both purposeful and decisively shows its intention to cleave through the atmosphere, charging forward, FAST!”

Ridiculous, right? If you ask us, the styling of the 990 looks more compact and centralized compared to the 790 and 890, especially the tail section, which looks even more truncated than before and leaves the rear wheel/tire hanging out into the open quite a bit. However, with a license plate bracket in place that empty space should fill out. The front profile of the bike is dominated by the 3.8-gallon fuel tank.

Ergonomically, the 990 Duke puts the rider in a slightly different position. The new seat design has the seat angle moved 2º upward in the front section so the rider isn’t constantly sliding forward into the tank. Overall seat height is 32.4 inches. The passenger seat is also moved up 20mm compared to the 890 Duke.

The pegs are constructed from aluminum with a rubber insert to help absorb vibrations and keep them away from you. The toe cap is also moved 10mm closer to keep the overall profile more compact.