KICKSTART YOUR OFFROAD RACING CAREER

KTM 125 XC

KTM 125 XC 2021

An all-new addition to the KTM XC model family for MY21, the KTM 125 XC is the most compact and lightweight of the full-size Cross-Country machines. Matching a lightweight Cross-Country specific chassis up with the most competitive 125 cc 2-stroke engine in the class, it delivers superior agility and power to fulfil the demands of any young and aspiring Offroad racer. This 2-stroke screamer is the ultimate entry point into the pro Offroad ranks.
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An all-new addition to the KTM XC model family for MY21, the KTM 125 XC is the most compact and lightweight of the full-size Cross-Country machines. Matching a lightweight Cross-Country specific chassis up with the most competitive 125 cc 2-stroke engine in the class, it delivers superior agility and power to fulfil the demands of any young and aspiring Offroad racer. This 2-stroke screamer is the ultimate entry point into the pro Offroad ranks.
  1. Engine & Exhaust
  2. Chassis
  3. Ergonomics & Comfort
  4. Bodywork & Graphics
  5. Software & Electronics

01. Engine & Exhaust

Light and powerful
Light and powerful

Engine

Featuring one of the most competitive and powerful engines in the 125 cc class, the KTM 125 XC is also equipped with an elextric starter. With an outstanding power-to-weight ratio, low cost and overall simplicity, it is clear that 2-strokes will continue to have a successful future at KTM. The compact and durable engine was developed using the latest KTM engineering know-how, resulting in broad power across the rev range. Its easy rideability and outstanding performance are benefits that equate to better race results.

Cylinder

At the heart of the 125 cc engine is a cylinder with a 54 mm bore. It features an improved power valve unit with a sophisticated mechanism designed for the lateral support exhaust ports. The exhaust port layout increases engine performance, while the upper contour of the exhaust port has been machined to ensure more accurate port timing. The two component cylinder head works in complete harmony with the cylinder to deliver outstanding performance across the entire rev range.

Crankcases and engine covers

The lightweight engine cases are manufactured using a high pressure die-cast production process, keeping wall thickness to a minimum while retaining strength and durability. The design allows for a high crankshaft position which is located near to the center of gravity, resulting in optimal mass centralization and easier rideability. The engine body is extremely compact, which contributes significantly to the low engine weight.

Transmission

The KTM 125 XC is fitted with a robust 6-speed transmission. The gearbox features a drive shaft which uses a screw for front sprocket fixation and diaphragm spring instead of a circlip, ensuring optimal front sprocket fixation. Another highlight of the KTM 125 XC transmission is the no-dirt gear shifter. Similar to the footpeg design, it prevents the build-up of dirt and ensures the next gear is always available, no matter the conditions.

Carburetor

The KTM 125 XC is fitted with a MIKUNI TMX 38 mm flat slide carburetor. Featuring latest technology reed blocks for the intake it offers optimal function, sealing and reliability, ensuring the whole system is always providing smooth and controllable power throughout the rev range.

Always optimal
Always optimal

Cooling

Maintaining the optimal engine temperature is crucial to ensuring consistent horsepower throughout the ride. The KTM 125 XC features radiators which are mounted low. This lowers the center of gravity and matches the design of the new shrouds perfectly in order to achieve perfect ergonomics. By using CFD technology (computational fluid dynamics) together with a clever coolant circuit routing, the innovative system ensures the optimum engine temperature for the highest performance, no matter what the conditions. The radiators also feature special protectors that serve not only as protection from flying rocks and debris but also as a brace that disperses energy around the radiators in the event of an impact.

Shaped for performance
Shaped for performance

Exhaust

When it comes to power delivery and performance, the exhaust developed specifically for this bike plays a key role and packs a punch that is hard to beat. In addition, its special shape provides slimmer ergonomics while still operating safely within the noise limits for racing.

Light and powerful
Light and powerful

Engine

Featuring one of the most competitive and powerful engines in the 125 cc class, the KTM 125 XC is also equipped with an elextric starter. With an outstanding power-to-weight ratio, low cost and overall simplicity, it is clear that 2-strokes will continue to have a successful future at KTM. The compact and durable engine was developed using the latest KTM engineering know-how, resulting in broad power across the rev range. Its easy rideability and outstanding performance are benefits that equate to better race results.

Light and powerful

Cylinder

At the heart of the 125 cc engine is a cylinder with a 54 mm bore. It features an improved power valve unit with a sophisticated mechanism designed for the lateral support exhaust ports. The exhaust port layout increases engine performance, while the upper contour of the exhaust port has been machined to ensure more accurate port timing. The two component cylinder head works in complete harmony with the cylinder to deliver outstanding performance across the entire rev range.

Crankcases and engine covers

The lightweight engine cases are manufactured using a high pressure die-cast production process, keeping wall thickness to a minimum while retaining strength and durability. The design allows for a high crankshaft position which is located near to the center of gravity, resulting in optimal mass centralization and easier rideability. The engine body is extremely compact, which contributes significantly to the low engine weight.

Transmission

The KTM 125 XC is fitted with a robust 6-speed transmission. The gearbox features a drive shaft which uses a screw for front sprocket fixation and diaphragm spring instead of a circlip, ensuring optimal front sprocket fixation. Another highlight of the KTM 125 XC transmission is the no-dirt gear shifter. Similar to the footpeg design, it prevents the build-up of dirt and ensures the next gear is always available, no matter the conditions.

Carburetor

The KTM 125 XC is fitted with a MIKUNI TMX 38 mm flat slide carburetor. Featuring latest technology reed blocks for the intake it offers optimal function, sealing and reliability, ensuring the whole system is always providing smooth and controllable power throughout the rev range.

Always optimal
Always optimal

Cooling

Maintaining the optimal engine temperature is crucial to ensuring consistent horsepower throughout the ride. The KTM 125 XC features radiators which are mounted low. This lowers the center of gravity and matches the design of the new shrouds perfectly in order to achieve perfect ergonomics. By using CFD technology (computational fluid dynamics) together with a clever coolant circuit routing, the innovative system ensures the optimum engine temperature for the highest performance, no matter what the conditions. The radiators also feature special protectors that serve not only as protection from flying rocks and debris but also as a brace that disperses energy around the radiators in the event of an impact.

Always optimal
Shaped for performance
Shaped for performance

Exhaust

When it comes to power delivery and performance, the exhaust developed specifically for this bike plays a key role and packs a punch that is hard to beat. In addition, its special shape provides slimmer ergonomics while still operating safely within the noise limits for racing.

Shaped for performance

02. Chassis

Optimal control
Optimal control

Frame

The high-tech, lightweight chrome-moly steel frame has a knack for easy handling, outlandish rideability, precise cornering and excellent stability. You can also count on high torsional rigidity and low longitudinal stiffness. This results in better absorption of the energy created from the front and rear suspension, sucking up jumps and bumps. In short: more comfort and less rider fatigue. Laterally attached, lightweight engine head stays (the connection between cylinder head and frame) contribute to a low vibration level. In addition, it is easy to maintain and to work on and supplies ample space for the tank and other components. The bike also features an extra-light subframe made of aluminum, which tiptoes the scales at less than 2 pounds.

Swingarm

The cast aluminum design offers low weight and a perfect flex behavior. The single-component casting process eliminates any inconsistencies and inherent weak points created by welding. It's better looking too.

Wheels

The 125 XC is fitted with lightweight, CNC-machined hubs, high-end Giant rims and black spokes with lightweight aluminum nipples providing maximum stability at minimum weight. The latest Dunlop Geomax AT81 tires guarantee perfect traction and outstanding performance.

Front suspension

All XC-W models are fitted with the latest 48 mm diameter WP XPLOR upside-down forks, featuring a split fork design developed by WP and KTM. It is fitted with a spring on both sides, but features separated functions for each fork leg: compression damping is fitted on the left side, while rebound is on the right. So the fork can easily be adjusted for compression and rebound with the twist of a dial on top of the fork tubes (30 clicks each). Although already distinguished for outstanding response and damping characteristics, the fork features a calibrated mid-valve piston for consistent damping. The settings keep the front end higher in the stroke, providing impressive reserves against bottoming out.

Rear suspension

The KTM 125 XC features a WP XACT monoshock, which has been developed to work as a complete unit with the entire frame and swingarm architecture, as well as the linkage system and the WP XACT fork. It features high-quality machined and anodized components, which add a touch of class and give it appeal beyond just a functional necessity. It is fully adjustable, including high and low speed compression, allowing you to set the shock up precisely to suit any track and rider's preferences.

Triple clamp

Top quality, CNC machined triple clamps have been a KTM trademark for years to ensure precise handling. The rubber damped handlebar fixation allows for two positions and an hourmeter is fitted in order to let the rider know it's time for a service.

Superior braking feel
Superior braking feel

Brakes

You couldn't brake any harder, better, faster or stronger. These high-tech Brembo S.p.A brakes are combined with lightweight Wave brake discs and are the ultimate solution in braking technology. First you outrun them, then you outbrake them.

Simple and effective
Simple and effective

Fuel tank

This is a lightweight polyethylene tank with a capacity of 2.4 gallons. Manufactured using see‐through plastic, you will always be able to see how much fuel remains at a glance.

Simple and effective
Simple and effective

Airbox

The air filter box design offers maximum protection of the air filter against soiling, while ensuring maximum airflow, and together with the intake snorkels, results in optimal power and throttle response. The large Twin Air B.V air filter is mounted on a stiff cage, which at the same time holds the system in place. This design is so simple, you could still pop a fresh one in with a face full of mud. Without tools. In seconds.

Optimal control
Optimal control

Frame

The high-tech, lightweight chrome-moly steel frame has a knack for easy handling, outlandish rideability, precise cornering and excellent stability. You can also count on high torsional rigidity and low longitudinal stiffness. This results in better absorption of the energy created from the front and rear suspension, sucking up jumps and bumps. In short: more comfort and less rider fatigue. Laterally attached, lightweight engine head stays (the connection between cylinder head and frame) contribute to a low vibration level. In addition, it is easy to maintain and to work on and supplies ample space for the tank and other components. The bike also features an extra-light subframe made of aluminum, which tiptoes the scales at less than 2 pounds.

Optimal control

Swingarm

The cast aluminum design offers low weight and a perfect flex behavior. The single-component casting process eliminates any inconsistencies and inherent weak points created by welding. It's better looking too.

Wheels

The 125 XC is fitted with lightweight, CNC-machined hubs, high-end Giant rims and black spokes with lightweight aluminum nipples providing maximum stability at minimum weight. The latest Dunlop Geomax AT81 tires guarantee perfect traction and outstanding performance.

Front suspension

All XC-W models are fitted with the latest 48 mm diameter WP XPLOR upside-down forks, featuring a split fork design developed by WP and KTM. It is fitted with a spring on both sides, but features separated functions for each fork leg: compression damping is fitted on the left side, while rebound is on the right. So the fork can easily be adjusted for compression and rebound with the twist of a dial on top of the fork tubes (30 clicks each). Although already distinguished for outstanding response and damping characteristics, the fork features a calibrated mid-valve piston for consistent damping. The settings keep the front end higher in the stroke, providing impressive reserves against bottoming out.

Rear suspension

The KTM 125 XC features a WP XACT monoshock, which has been developed to work as a complete unit with the entire frame and swingarm architecture, as well as the linkage system and the WP XACT fork. It features high-quality machined and anodized components, which add a touch of class and give it appeal beyond just a functional necessity. It is fully adjustable, including high and low speed compression, allowing you to set the shock up precisely to suit any track and rider's preferences.

Triple clamp

Top quality, CNC machined triple clamps have been a KTM trademark for years to ensure precise handling. The rubber damped handlebar fixation allows for two positions and an hourmeter is fitted in order to let the rider know it's time for a service.

Superior braking feel
Superior braking feel

Brakes

You couldn't brake any harder, better, faster or stronger. These high-tech Brembo S.p.A brakes are combined with lightweight Wave brake discs and are the ultimate solution in braking technology. First you outrun them, then you outbrake them.

Superior braking feel
Simple and effective
Simple and effective

Fuel tank

This is a lightweight polyethylene tank with a capacity of 2.4 gallons. Manufactured using see‐through plastic, you will always be able to see how much fuel remains at a glance.

Simple and effective
Simple and effective
Simple and effective

Airbox

The air filter box design offers maximum protection of the air filter against soiling, while ensuring maximum airflow, and together with the intake snorkels, results in optimal power and throttle response. The large Twin Air B.V air filter is mounted on a stiff cage, which at the same time holds the system in place. This design is so simple, you could still pop a fresh one in with a face full of mud. Without tools. In seconds.

Simple and effective

03. Ergonomics & Comfort

Centralized control
Centralized control

Handlebar

All full-size KTM XC models are equipped with the same high-strength aluminum tapered handlebar, made by NEKEN. The handlebar is fixed in rubber damped mountings, which allow for two different positions. The handlebars come standard with an ODI vulcanized grip on the right side and a comfortable ODI lock-on grip, which does not require any wire or glue, on the left. They also feature a bar-pad with a cover that can be attached and removed with little effort.

Innovative engineering
Innovative engineering

Footpegs

Sophisticated ´No Dirt´ footpegs prevent jamming up the pegs, even when digging in deep ruts. The pegs on the Cross-Country models are 6 mm higher than the ones used on SX models, which benefits ground clearance. But you can swap them at will.

Supreme manoeuvrability
Supreme manoeuvrability

Seat

The XC range features state-of-the-art seat technology with a newly shaped surface that provides improved ergonomics and much better seat comfort thanks to higher foam padding. The seat is conveniently fixed to the bike using one long, lateral screw, making it easy to handle.

Centralized control
Centralized control

Handlebar

All full-size KTM XC models are equipped with the same high-strength aluminum tapered handlebar, made by NEKEN. The handlebar is fixed in rubber damped mountings, which allow for two different positions. The handlebars come standard with an ODI vulcanized grip on the right side and a comfortable ODI lock-on grip, which does not require any wire or glue, on the left. They also feature a bar-pad with a cover that can be attached and removed with little effort.

Centralized control
Innovative engineering
Innovative engineering

Footpegs

Sophisticated ´No Dirt´ footpegs prevent jamming up the pegs, even when digging in deep ruts. The pegs on the Cross-Country models are 6 mm higher than the ones used on SX models, which benefits ground clearance. But you can swap them at will.

Innovative engineering
Supreme manoeuvrability
Supreme manoeuvrability

Seat

The XC range features state-of-the-art seat technology with a newly shaped surface that provides improved ergonomics and much better seat comfort thanks to higher foam padding. The seat is conveniently fixed to the bike using one long, lateral screw, making it easy to handle.

Supreme manoeuvrability

04. Bodywork & Graphics

Aggressively styled
Aggressively styled

Decals

The durable in-mold graphics convey the READY TO RACE character of the KTM XC model line.

Aggressively styled
Aggressively styled

Decals

The durable in-mold graphics convey the READY TO RACE character of the KTM XC model line.

Aggressively styled

05. Software & Electronics

Technical Details

Engine

  • Transmission 6-speed
  • Starter Kick and electric starter
  • Stroke 54.5 mm
  • Bore 54 mm
  • Clutch Multi-plate clutch, Brembo hydraulics
  • Displacement 124.8 cm³
  • EMS Kokusan
  • Design 1-cylinder, 2-stroke engine

Chassis

  • Weight (without fuel) 88 kg
  • Tank capacity (approx.) 10 l
  • Front brake disc diameter 260 mm
  • Rear brake disc diameter 220 mm
  • Front brake Disc brake
  • Rear brake Disc brake
  • Chain 5/8 x 1/4"
  • Frame design Central double-cradle-type 25CrMo4 steel
  • Front suspension WP XACT-USD, Ø 48 mm
  • Ground clearance 370 mm
  • Rear suspension WP XACT Monoshock with linkage
  • Seat height 950 mm
  • Steering head angle 63.9 °
  • Suspension travel (front) 310 mm
  • Suspension travel (rear) 300 mm