2027 KTM SX range explained: from 50s to 450s
KTM has lifted the covers from its 2027 SX motocross range, and it is a broad one. KTM counts the line-up as nine model families, though the 85 SX is offered in two wheel-size configurations, giving riders a pathway from the 50 SX and 65 SX junior machines, through the 85 SX, 125 SX, 250 SX, 300 SX, 250 SX-F, 350 SX-F and 450 SX-F. KTM’s own model pages list three 2027 SX-F four-strokes and seven 2027 SX two-stroke model pages when the two 85 SX wheel-size options are counted separately.
The simplest way to view the range is as a motocross ladder. The 50 SX gives young riders their first taste of a proper KTM mini motocrosser, the 65 SX adds a manual gearbox and clutch, while the 85 SX is the final junior step before the full-size bikes. From there, KTM offers the 125 SX for small-bore two-stroke racing, 250 SX and 300 SX for riders who still want the smell, sound and immediacy of a big two-stroke, then the 250 SX-F, 350 SX-F and 450 SX-F four-strokes for the more conventional modern motocross route.
For 2027, the obvious visual change is the latest KTM orange-heavy look, with red highlights on the tank spoilers and in-moulded graphics. KTM says the decals are designed to be more durable than traditional surface-applied stickers.
Two-stroke sound and smell meets modern hardware…
The bigger two-strokes remain one of the more interesting parts of the 2027 KTM motocross range. The 125 SX, 250 SX and 300 SX keep the light weight, sound and response that two-stroke fans continue to chase, but bring that old-school character into the modern era with electronic fuel injection, electronic management and electric start.
KTM’s full-size two-stroke SX models use Keihin EFI with a 39 mm throttle body and Vitesco Technologies EMS, while the 125 SX runs a six-speed transmission and the 250 SX and 300 SX run five-speed gearboxes. The 300 SX is listed at 293.2 cc and 99.4 kg without fuel, the 250 SX at 249 cc and 99.4 kg, and the 125 SX at 124.8 cc and 92 kg.
The bigger two-strokes also get a map select switch, allowing riders to choose between a more linear map and a sharper, more aggressive setting. KTM positions that as a way to keep the explosive two-stroke delivery, while making the bikes more tunable to track conditions and rider preference.
| 2027 KTM SX Two-Stroke Motocross Range | |
|---|---|
| Model | Key specifications |
| KTM 300 SX | 293.2 cc single-cylinder two-stroke Five-speed transmission Keihin EFI, 39 mm throttle body / Vitesco Technologies EMS Wet DDS multi-disc clutch, Brembo hydraulics Central double-cradle-type 25CrMo4 steel frame Aluminium-reinforced polyamide rear subframe WP XACT-USD AER 48 mm fork / WP XACT linkage shock 310 mm front / 300 mm rear suspension travel Disc brakes front and rear 520 non-sealed chain 958 mm seat height / 354 mm ground clearance 7.2-litre tank / 99.4 kg without fuel |
| KTM 250 SX | 249 cc single-cylinder two-stroke Five-speed transmission Keihin EFI, 39 mm throttle body / Vitesco Technologies EMS Wet DDS multi-disc clutch, Brembo hydraulics Central double-cradle-type 25CrMo4 steel frame Aluminium-reinforced polyamide rear subframe WP XACT-USD AER 48 mm fork / WP XACT linkage shock 310 mm front / 300 mm rear suspension travel Disc brakes front and rear 520 non-sealed chain 958 mm seat height / 354 mm ground clearance 7.2-litre tank / 99.4 kg without fuel |
| KTM 125 SX | 124.8 cc single-cylinder two-stroke Six-speed transmission Keihin EFI, 39 mm throttle body / Vitesco Technologies EMS Wet multi-disc DS clutch, Brembo hydraulics Central double-cradle-type 25CrMo4 steel frame Aluminium-reinforced polyamide rear subframe WP XACT-USD AER 48 mm fork / WP XACT linkage shock 310 mm front / 300 mm rear suspension travel Disc brakes front and rear 520 non-sealed chain 958 mm seat height / 359 mm ground clearance 7.2-litre tank / 92 kg without fuel |
| KTM 85 SX 19/16 | 84.9 cc single-cylinder two-stroke Six-speed transmission Keihin PWK 28 Wet multi-disc clutch, Formula hydraulics Central-tube frame with double-cradle Aluminium / polyamide glass fibre rear subframe XACT 43 mm WP upside-down fork / XACT WP PDS monoshock 278 mm front / 289 mm rear suspension travel Disc brakes front and rear 428 non-sealed chain 871 mm seat height / 333 mm ground clearance 5.4-litre tank / 69 kg without fuel |
| KTM 85 SX 17/14 | 84.9 cc single-cylinder two-stroke Six-speed transmission Keihin PWK 28 Wet multi-disc clutch, Formula hydraulics Central-tube frame with double-cradle Aluminium / polyamide glass fibre rear subframe XACT 43 mm WP upside-down fork / XACT WP PDS monoshock 278 mm front / 289 mm rear suspension travel Disc brakes front and rear 428 non-sealed chain 845 mm seat height / 308 mm ground clearance 5.4-litre tank / 68 kg without fuel |
| KTM 65 SX | 64.9 cc single-cylinder two-stroke Six-speed transmission Mikuni VM 24 Wet multi-disc clutch, Formula hydraulics Central-tube frame with double-cradle Steel / polyamide glass fibre rear subframe XACT 35 mm WP upside-down fork / XACT WP monoshock 215 mm front / 253.5 mm rear suspension travel Disc brakes front and rear 420 chain 730 mm seat height / 259 mm ground clearance 4.5-litre tank / 54.3 kg without fuel |
| KTM 50 SX | 49.9 cc single-cylinder two-stroke Single-speed transmission Dell’Orto PHBG 19 BS Adjustable centrifugal clutch Central-tube frame with double-cradle Steel / polyamide glass fibre rear subframe XACT 35 mm WP upside-down fork / XACT WP monoshock 165 mm front / 190.5 mm rear suspension travel Disc brakes front and rear 415 non-sealed chain 653 mm seat height / 233 mm ground clearance 2.3-litre tank / 43.5 kg without fuel |
Four-strokes remain the race-team staples
For riders chasing the established four-stroke path, the 2027 KTM SX-F range comprises the 250 SX-F, 350 SX-F and 450 SX-F. All three use single-cylinder, four-stroke engines, Keihin EFI with a 44 mm throttle body, five-speed transmissions, WP XACT 48 mm AER forks and WP XACT linkage rear suspension.
The 250 SX-F remains the MX2-style high-revving option at 249.9 cc and 101.5 kg without fuel. The 350 SX-F continues as KTM’s middle ground between 250 agility and 450 torque, listed at 349.7 cc and 102.4 kg. The 450 SX-F sits at the top of the range, with 449.9 cc and a listed weight of 103.1 kg without fuel.
| 2027 KTM SX-F Four-Stroke Motocross Range | |
|---|---|
| Model | Key specifications |
| KTM 250 SX-F | 249.9 cc single-cylinder four-stroke Five-speed transmission Keihin EFI, 44 mm throttle body / Keihin EMS Wet multi-disc DS clutch, Brembo hydraulics Central double-cradle-type 25CrMo4 steel frame Aluminium-reinforced polyamide rear subframe WP XACT-USD AER 48 mm fork / WP XACT linkage shock 310 mm front / 300 mm rear suspension travel Disc brakes front and rear 520 non-sealed chain 958 mm seat height / 343 mm ground clearance 7.2-litre tank / 101.5 kg without fuel |
| KTM 350 SX-F | 349.7 cc single-cylinder four-stroke Five-speed transmission Keihin EFI, 44 mm throttle body / Keihin EMS Wet multi-disc DS clutch, Brembo hydraulics Central double-cradle-type 25CrMo4 steel frame Aluminium-reinforced polyamide rear subframe WP XACT-USD AER 48 mm fork / WP XACT linkage shock 310 mm front / 300 mm rear suspension travel Disc brakes front and rear 520 non-sealed chain 958 mm seat height / 343 mm ground clearance 7.2-litre tank / 102.4 kg without fuel |
| KTM 450 SX-F | 449.9 cc single-cylinder four-stroke Five-speed transmission Keihin EFI, 44 mm throttle body / Keihin EMS Wet DDS multi-disc clutch, Brembo hydraulics Central double-cradle-type 25CrMo4 steel frame Aluminium-reinforced polyamide rear subframe WP XACT-USD AER 48 mm fork / WP XACT linkage shock 310 mm front / 300 mm rear suspension travel Disc brakes front and rear 520 non-sealed chain 958 mm seat height / 343 mm ground clearance 7.2-litre tank / 103.1 kg without fuel |
Common chassis and suspension themes
Across the full-size SX and SX-F machines, KTM uses a central double-cradle-type 25CrMo4 steel frame, aluminium-reinforced polyamide rear subframe, WP XACT 48 mm AER fork and WP XACT monoshock with linkage. KTM’s technical details list 310 mm of front suspension travel and 300 mm at the rear across the full-size models.
KTM also continues with tool-free suspension adjustment as a key feature. The WP fork allows external adjustment for air pressure, compression and rebound, while the rear shock offers hand-adjustable compression options. KTM also highlights improved serviceability, with tool-free air filter access and a design aimed at simplifying trackside maintenance.
Mini motocrossers: 50 SX, 65 SX and 85 SX
The junior range is where the progression story is clearest. The 50 SX uses a 49.9 cc two-stroke engine, single-speed transmission and adjustable centrifugal clutch. It is listed at 43.5 kg without fuel, with a 653 mm seat height.
The 65 SX steps things up with a 64.9 cc two-stroke engine, six-speed transmission and wet multi-disc clutch with Formula hydraulics. KTM also highlights adjustability on the 65 SX, with height-adjustable suspension, handlebar position, subframe and bodywork, giving younger riders a better chance of growing with the bike.
The 85 SX remains available in 17/14 and 19/16 wheel combinations. Both use an 84.9 cc two-stroke engine, six-speed gearbox, Keihin PWK 28 carburettor and WP XACT suspension, with the larger-wheel 19/16 model listed at 69 kg and the smaller 17/14 model at 68 kg, both measured without fuel.
The 2027 KTM minicycles are due to begin arriving at authorised KTM dealers in Australia from June 2026 and in New Zealand from July 2026, with the larger SX and SX-F models to follow in Australia from July 2026 and in New Zealand from August 2026.
