When the Guerrilla 450 first launched in 2024, comparisons to the KTM 390 Duke (now known as the Duke R) were inevitable. In 2026 though, things have changed because, following the revised GST structure on motorcycles, Bajaj decided to downsize all of its 400cc manufactured bikes to fall below the 350cc threshold. So, we now have a 390 Duke with a 349cc engine and the 398cc version continues on as the 390 Duke R. Meanwhile, the Royal Enfield Guerrilla 450 is now available in a new, sportier Apex variant. Let’s see how the motorcycles compare on paper with these redrawn boundaries.
KTM 390 Duke vs Royal Enfield Guerrilla 450 Apex: Engine and output
KTM has more power, Guerrilla has more torque
KTM 390 Duke | Royal Enfield Guerrilla 450 Apex | |
Engine | 349.32cc, single-cylinder, liquid-cooled | 452cc, single-cylinder, liquid-cooled |
Power | 41.5hp at 8,600rpm | 40.02hp at 8,000rpm |
Torque | 33.5Nm at 7,000rpm | 40Nm at 5,500rpm |
Transmission | 6-speed | 6-speed |
Power-to-weight ratio | 246.58hp/tonne | 216.32hp/tonne |
The biggest reason for this comparison is the KTM’s downsized 349cc engine. It now makes 41.5hp of power (vs 46hp on the Duke R) and 33.5Nm of torque (vs 39Nm on the Duke R). Both are now delivered slightly later in rev range as well. KTM achieved this with an 8mm shorter stroke length, although the bore remains unchanged. The Guerrilla 450 Apex, on the other hand, has not changed on the engine front and retains its 452cc engine with the same power and torque figures. Thus, the Guerrilla offers quite a bit more torque than the Duke and it’s delivered much earlier in the rev range too. Which means you will have to work the throttle and gearbox comparatively less on the Royal Enfield. Thus, if you spend most of your time in the city, it will be the less cumbersome bike to ride in this regard.
KTM 390 Duke vs Royal Enfield Guerrilla 450 Apex: Dimensions and weight
Duke is lighter despite a 30 percent larger fuel tank
KTM 390 Duke | Royal Enfield Guerrilla 450 Apex | |
Fuel tank capacity | 15 litres | 11 litres |
Ground clearance | 183mm | 169mm |
Kerb weight | 168.3kg | 185kg |
Seat height | 800mm | 780mm |
Wheelbase | 1357mm | 1440mm |
The 390 Duke continues to be far lighter than the Guerrilla, which weighs a staggering 17kg more. Another pertinent detail is that despite the lower weight, the Duke gets a 4-litre larger fuel tank compared to the Guerrilla. The Guerrilla does get a 20mm lower seat height and its ground clearance is 14mm lesser than the Duke. However, it’s worth noting that both bikes are perfectly usable on our roads, pothole-ridden or otherwise.
KTM 390 Duke vs Royal Enfield Guerrilla 450 Apex: Tyres, brakes, and suspension
Duke has adjustable suspension and better brakes
KTM 390 Duke | Royal Enfield Guerrilla 450 Apex | |
Tyres (F, R) | 110/70R17, 150/60R17 | 120/70R17, 160/60R17 |
Brakes (F, R) | 320mm front disc, 240mm rear disc; dual-channel ABS | 310mm front disc, 270mm rear disc; dual-channel ABS |
Suspension (F, R) | 43mm USD fork, monoshock | 43mm RSU fork, linkage monoshock |
Moving on to one of the most important links between the rider and the tarmac, the tyres. The Guerrilla gets slightly wider tyres than the Duke at both ends, but the disc brakes on the Guerrilla are slightly smaller at the front, and slightly larger at the rear. However, the KTM comes with a more sophisticated radial calliper at the front, whereas the Guerrilla makes do with a simpler axial unit. As for suspension, the Duke gives you an USD fork which is compression and rebound adjustable; and the rear monoshock is rebound and preload adjustable. The only adjustability the Guerrilla gets is for its rear preload.
KTM 390 Duke vs Royal Enfield Guerrilla 450 Apex: Features
KTM continues its tech-forward approach
KTM has always offered a myriad of tech features and rider aids on its motorcycles. Royal Enfield on the other hand has always been restrained on that front, prioritizing simplicity and ease of use instead. Depending on your preferences, you will gravitate towards one or the other. KTM offers you slip-and-assist clutch, ride modes, traction control, launch control, lean-sensitive ABS, bi-directional quickshifter, cruise control, turn-by-turn navigation, track screen, and a type-C charging port. Royal Enfield, to its credit, has given the Guerrilla a decent feature-set comprising a TFT instrument cluster which allows you to screencast Google Maps, two ride modes and a slip-and-assist clutch.
KTM 390 Duke vs Royal Enfield Guerrilla 450 Apex: Price
Guerrilla is more affordable with a bigger engine but has less features
| KTM 390 Duke | Royal Enfield Guerrilla 450 Apex | |
| Price | Rs 2.84 lakh (ex-showroom, Delhi) | Rs 2.51 lakh (ex-showroom, Chennai) |
Last but not least, the other reason necessitating the comparison, is the price. With its downsized engine KTM was able to meet a lower GST slab and thus the 390 Duke now costs Rs 2.84 lakh (ex-showroom, Delhi). The Guerrilla 450 Apex still manages to undercut it and by a good deal, starting at Rs 2.51 lakh and going up to Rs 2.58 lakh for the Apex Green colour.