2016 KTM SX Two-Stroke Motocross Bikes: FIRST LOOK

Kit Palmer | May 19, 2015

Alongside its four-stroke MX models, KTM also introduced its 2016 125, 150 and 250 SX two-stroke models. The big news here is the 125 and 150 SXs getting all-new motors. The 125’s motor, now lighter and more compact, is claimed to have more power across the rev range. KTM also says that the motor is 4.4 pounds lighter than before. The 150 gets many of the same motor updates as the 125.

All of the two-strokes also share similar frames as the four-strokes.

2016 KTM 125 SX Highlights

ENGINE

• New 125 SX engine is more compact, is 4.4 pounds lighter and has more power for class dominance

• New cylinder with revised ports and newly designed power valve unit with a sophisticated mechanism for the lateral exhaust ports gives a massive performance increase over the entire range

• A new piston is optimized for maximum reliability with the new cylinder layout

• Lighter crankshaft is optimally balanced for minimum vibrations

• All-new die-cast engine cases raise the crankshaft and clutch shaft, centralizing mass and improving handling

• New 6-Speed transmission provides the same gear ratios as before but is lighter and narrower

• New “No Dirt” shift lever prevents dirt from fouling the lever joint to ensure proper shifting in any condition

• New exhaust pipe has been tuned for the 125SX specifically to get maximum power output from the new engine

CHASSIS

• New lighter Chromoly steel frame provides higher torsional rigidity with less longitudinal stiffness resulting in improved handling and energy absorption

• New smaller, lighter subframe design made with new aluminum profiles

• New lighter swingarm features a revised internal structure to match the new frame characteristics

• New lighter “No Dirt” footpeg design that provides a larger surface area and features a “scraper” to reduce dirt build-up in the hinge

• New CNC machined upper triple clamp featuring a rubber damping system for the new Neken handlebar and ODI lock-on grips

• The advanced WP 4CS (Four Chamber System) Fork has been specifically designed for Motocross and features revised damping settings optimized for the new chassis

• New generation WP shock has been developed in conjunction with the new frame and swingarm architecture including a new linkage/pullrod system

• Super lightweight Galfer Wave rotors, CNC machined hubs, high-end Excel rims fitted with Dunlop GEOMAX MX32 tires are standard equipment

• New airbox and airfilter design offers maximum protection for the engine while ensuring maximum airflow and providing quick “no tools” airfilter changes

• New ergonomics and bodywork centralize mass, improve handling and rider comfort

SPECIFICATIONS

Engine Type: Single cylinder, 2-stroke

Displacement: 124.8cc

Bore / Stroke: 54.0 / 54.5mm

Starter: Kickstarter

Transmission: 6 gears

Fuel System: Keihin PWK 38S AG carburetor

Lubrication: Premix 40:1

Primary Ratio: 23:73

Final Drive: 13:50

Cooling: Liquid

Clutch: Wet nulti-disc clutch, Brembo hydraulics

Ignition: Kokusan

Frame: Central double-cradle type 25CrMo4 steel

Subframe: Aluminum

Handlebar: Neken, aluminum Ø 28/22mm

Front Suspension: WP USD 4860 MXMA 4CS

Rear Suspension: WP monoshock 5018 BAVP DCC w/linkage

Suspension Travel front/rear: 300mm/11.81 in.; 300mm/11.81 in.

Front/Rear Brakes: Disc Brake 260mm/10.24 in.; 220mm/8.66 in.

Front/Rear Rims: 1.60×21, 2.15×19 Excel

Front/Rear Tires: 80/100-21 in.; 100/90-19 in. Dunlop MX32

Chain: 5/8 x 1/4 in

Silencer: Aluminum

Steering Head Angle: 26.1º

Triple Clamp Offset: 22mm

Wheelbase: 1,485mm ± 10mm / 58.5 ± 0.4 in.

Ground Clearance: 375mm / 14.8 in.

Seat Height: 960 mm / 37.8 in.

Tank Capacity, Approx: 7.2L / 1.9 gal.

Weight (without fuel), Approx: 89.2 kg / 196.7 lbs

2016 KTM 150 SX Highlights

ENGINE

• New 150 SX engine is more compact, weighs four pounds less and has more power for class dominance

• New cylinder with revised ports and newly designed power valve unit with a sophisticated mechanism for the lateral exhaust ports gives a massive performance increase over the entire range

• A new piston is optimized for maximum reliability with a reworked shape to fit perfectly with the new cylinder layout

• Lighter crankshaft is optimally balanced for minimum vibrations

• All-new die-cast engine cases raise the crankshaft and clutch shaft, centralizing mass and improving handling

• New 6-Speed transmission provides the same gear ratios as before but is lighter and narrower

• New “No Dirt” shift lever prevents dirt from fouling the lever joint to ensure proper shifting in any condition

• New exhaust pipe has been tuned for the 150 SX specifically to get maximum power output from the new engine