2024 KTM 390 Duke Review [10 Fast Facts]

April 1, 2024

Pop the confetti because this year marks the 30th anniversary of KTM’s rambunctious Duke family of motorcycles. The orange brand’s first street bike was the Duke 620, which ushered in a generation of riders partial to skids, stoppies, and wheelies. Hooligan behavior is intrinsic to the Duke range’s DNA from top to bottom, where we have every rowdy rung in the displacement ladder covered here in the States—the 250, 390, 790, 990 Duke, and their champion, the 1390 Super Duke R Evo. But which model best captures the Duke essence for new and returning riders? The virtually all-new 2024 KTM Duke 390.

KTM says its entry-level friendly, though quite sassy, single-cylinder-powered naked sportbike is 90 percent new for the year. A larger-displacement LC4c engine, an all-new chassis, fresh suspension, a swath of electronic rider aids, and new styling back up that claimed figure. Impressively, the KTM-designed/Bajaj-manufactured steed comes to our shores with the same $5899 MSRP as last year’s model. New stuff at the same price? That isn’t something we see often.

We headed to Europe’s only desert near Almería, Spain, where we raced around mountain roads, lane-split through tiny villages, and even took to the freeways to hit you with the Fast Facts.

The 390 is all grown up—the LC4c single-cylinder engine increases displacement from 373cc to 399cc, gaining a touch of power. This thumper is lively, spinning up vigorously and connecting the dots to its larger sibling in spirit. On paper, the all-new engine is wholly reworked, keeping the same 89mm bore and relying on lengthening the stroke to 64mm for an additional 26cc. The 390 cranks out a claimed 45 horsepower at 8500 rpm and 29 ft-lbs of torque at 7000 rpm, and yearns to have the ride-by-wire whip cracked. Sure, performance figures have only risen by single digits. Still, their peaks are reached dramatically lower in the rev range—1000 rpm earlier when talking horsepower and 250 revs sooner concerning torque, making its friendly yet engaging midrange and top-end power even more accessible.

What else is new? Just about everything inside the motor. The Austrians call this engine the LC4c, which, in KTM-speak, translates to “Liquid Cooled, 4-valve, compact.” The only returning elements are the DOHC valvetrain, bore, and single-cylinder configuration, though just looking at the cases alone is a dead giveaway that changes are afoot. Meanwhile, everything else focuses on efficiency, from the lighter, more compact cylinder-head design to the updated cooling system, faster warm-up times, and, finally, longer service intervals. What’s important is the larger volume airbox and intake system, rounded out by a Euro 5+ compliant exhaust system that does its parts to broaden the engine’s powerband. It all stacks up to an aggressive little Duke that pulls hard, and vibes make themselves known later in the powerband—not unheard of with single-cylinder engines.

Three ride modes are standard and help access the 2024 KTM 390 Duke’s class-leading rider aids. Track, Sport, and Rain modes are standard when navigating the new five-inch, full-color TFT display. Fueling is good, though Sport is my preferred setting as it’s quite athletic without becoming snappy, which Track can do at low rpm. Also on deck is two-channel cornering ABS—a standard lean-sensitive mode and the hooligan-friendly Supermoto ABS setting that disables the rear. Adjustable traction control is also in play, which, when talking about this level of performance, isn’t entirely necessary, though it’s value-added for sketchy conditions. If you’re Ready To Race, you get a pitlane limiter and launch control. Along with the new looks comes all-around LED lighting.

The six-speed gearbox receives some updates. Sporty, light shifting is the name of the game on the 390 Duke, though we had the luxury of the optional up/down quickshifter ($247 MSRP). Small-displacement powerplants need to be kept on the boil, so opting for KTM’s Quickshifter+ will make quick work of rowing through the transmission. The new shift drum provides improved engagement when working the lever, especially when compared to the RC 390 that the Duke used to share its powerplant with.

An updated steel-trellis frame and curved, open-lattice swingarm join the fold in 2024, adding much-needed rigidity to the KTM 390 Duke’s chassis. Keen-eyed observers will note that the diecast aluminum subframe visually ties it to its larger-displacement siblings. The new offset monoshock accommodates the larger under-seat airbox and allows the seat height to drop half an inch to 32.3 inches. Bending the 390 into a curve feels rapidly responsive, and veterans will be resetting their entry points. It delivers a pure, uninhibited, lightweight riding experience at the same 364-pound wet weight as before. Special thanks to its nimble nature go to the updated wheels, saving nearly 10 pounds of unsprung mass, aiding its improved maneuverability, while the stiffened bits up the confidence ante when riding at pace.

The adjustable suspension offers something the competition doesn’t. If you haven’t noticed, the 390 Duke brings much to this class. While it does rest at the pricier end of the spectrum, you’re getting a lot of higher-end features not typically associated with the entry-level class, including its adjustable WP Apex suspension. The inverted fork is good for five clicks of compression and rebound damping adjustment, providing a noticeable change in setup when tweaked. At the rear end, the shock has adjustable rebound damping and spring preload—those pushing the 185+ mark will want to put a few turns on the spring. The result is suspension that soaks up rough stuff—until you’re using edging toward the bottom of the stroke—and provides support through all phases of the turn. Moreover, allowing newbies to fiddle with their setup instills good practices when they graduate to other machines.

A neutral riding position is in store on this naked machine. A narrow single-cylinder engine helps the wee Duke maintain slim sensations between the knees. When coupled with the accommodating 32.3-inch seat, the 2024 KTM 390 Duke becomes a hot option for riders with shorter inseams, as it’ll help them confidently plant their boots on the ground. Riders of my 5-foot-10 stature will be nudging up against the spatial limit. Its compact cockpit isn’t cramped for me, but those pushing six feet or beyond may disagree. The seat leans into the brand’s Ready To Race mantra with thin padding; longer rides can be taxing. Moreover, the cover material is curiously slippery. That said, there’s no excessive knee-bend, and aside from the aforementioned observations, it’ll treat most up-and-coming riders right.

ByBre brakes return to the fold. One of the few returning components for the 2024 KTM 390 Duke is its ByBre four-piston front caliper, gripping a 320mm disc. Feel at the adjustable lever is adequate and the steel-braided brake lines also firm up feedback. That’s a salty dog opinion, admittedly, while anyone just getting behind bars won’t be taken aback by excessively strong initial bite or power. In the rear, a two-piston caliper clamps onto a 240mm rotor and works as advertised.

Michelin Power 6 rubber is standard. KTM has paid for quality rubber with Michelin’s latest sport-touring Power 6 kicks. The mileage-centric tires aren’t afraid of a good rip in the Spanish canyons—on a motorcycle with moderate peak figures, they are a good match out on the roads. I was met with blustery, cold conditions—a challenging environment for anything black, round, and sticky, yet the Michelins handled themselves quite well.

Meet your gateway hooligan: The 2024 KTM 390 Duke is your ticket to a good time. The 250 Duke withstanding, the 390 Duke serves a few masters: All-important new riders, returning riders, and those that are downsizing. For the same MSRP as last year’s model, KTM’s feisty naked machine is an incredibly agile motorcycle that taps into the same sporty DNA seen in its bigger siblings, married to lively single-cylinder engine performance we can enjoy wrapping our heads around. Taking things further, this machine’s features put it head and shoulders above the competition in terms of performance potential. While it costs more, you get much more chassis, suspension, and electronics.

Action photography by Sebas Romero
Static location photography by Rudi Schedl
Studio photography by Kiska

RIDING STYLE

Helmet: Shoei X-Fifteen
Suit: Alpinestars GP Force Chaser
Gloves: Alpinestars SP-8 V3
Boots: Alpinestars Super Tech R

2024 KTM 390 Duke Specs

ENGINE

Type: Single cylinder
Displacement: 399cc
Bore x stroke: 89 x 64mm
Maximum torque: 29 ft-lbs
Maximum power: 44 horsepower
Valvetrain: DOHC; 4 valves
Fueling: Bosch EFI w/ 46mm throttle body
Lubrication: Wet sump
Transmission: 6-speed (quickshifter optional)
Clutch: Wet multiplate w/ assist and slipper functions
Final drive: Chain

CHASSIS

Frame: Powdercoated steel trellis w/ cast aluminum swingarm and removable cast aluminum subframe
Handlebars: Tapered aluminum
Front suspension; travel: Damping-adjustable WP Apex inverted 43mm open-cartridge fork; 5.9 inches
Rear suspension; travel: Cantilevered, linkage-less, rebound-damping adjustable WP Apex Separate Piston shock; 5.9 inches
Wheels: Cast aluminum
Front: 17 x 3.00
Rear: 17 x 4.00
Tires: Michelin Power 6
Front: 110/70 x 17
Rear: 150/60 x 17
Front brake: 320mm disc w/ radially mounted Bybre 4-piston caliper
Rear brake: 240mm disc w/ Bybre 2-piston floating caliper
ABS: Bosch 9.3 two-channel w/ Supermoto mode