Contents

1 MEANS OF REPRESENTATION
- 1.1 Symbols used
- 1.2 Formats used
2 SAFETY ADVICE
- 2.1 Use definition intended use
- 2.2 Misuse
- 2.3 Safety advice
- 2.4 Degrees of risk and symbols
- 2.5 Tampering warning
- 2.6 Safe operation
- 2.7 Protective clothing
- 2.8 Work rules
- 2.9 Environment
- 2.10 Owner's Manual
3 IMPORTANT NOTES
- 3.1 Manufacturer and implied warranty
- 3.2 Fuel, auxiliary substances
- 3.3 Spare parts, accessories
- 3.4 Service
- 3.5 Figures
- 3.6 Customer service
4 VIEW OF VEHICLE
- 4.1 View of vehicle, front left (example)
- 4.2 View of vehicle, rear right (example)
5 SERIAL NUMBERS
- 5.1 Vehicle identification number
- 5.2 Type label
- 5.3 Engine number
- 5.4 Fork part number
- 5.5 Shock absorber article number
6 CONTROLS
- 6.1 Clutch lever
- 6.2 Hand brake lever
- 6.3 Throttle grip
- 6.4 Kill switch
- 6.5 Opening fuel tank filler cap
- 6.6 Closing the fuel tank filler cap
- 6.7 Fuel tap
- 6.8 Choke
- 6.9 Shift lever
- 6.10 Kick starter lever
- 6.11 Foot brake lever
- 6.12 Plug-in stand
- 6.13 Service hour counter
7 PREPARING FOR USE
- 7.1 Advice on preparing for first use
- 7.2 Running in the engine
- 7.3 Preparing the vehicle for difficult operating conditions
- 7.4 Preparing the vehicle for riding on dry sand
- 7.5 Preparing the vehicle for riding on wet sand
- 7.6 Preparing the vehicle for riding on wet and muddy circuits
- 7.7 Preparing vehicle for high temperatures or slow riding
- 7.8 Preparing the vehicle for low temperatures or snow
8 RIDING INSTRUCTIONS
- 8.1 Checks and maintenance measures when preparing for use
- 8.2 Starting
- 8.3 Starting off
- 8.4 Shifting, riding
- 8.5 Applying the brakes
- 8.6 Stopping, parking
- 8.7 Transporting
- 8.8 Refueling
9 SERVICE SCHEDULE
- 9.1 Additional information
- 9.2 Required work
- 9.3 Recommended work
10 TUNING THE CHASSIS
- 10.1 Checking the basic chassis setting with rider's weight
- 10.2 Air suspension AER 48
- 10.3 Compression damping of the shock absorber
- 10.4 Adjusting the low-speed compression damping of the shock absorber
- 10.5 Adjusting the high-speed compression damping of the shock absorber
- 10.6 Adjusting the rebound damping of the shock absorber
- 10.7 Measuring the rear wheel dimension unloaded
- 10.8 Checking the static sag of the shock absorber
- 10.9 Checking the riding sag of the shock absorber
- 10.10 Adjusting the spring preload of the shock absorber
- 10.11 Adjusting the riding sag
- 10.12 Checking the basic setting of the fork
- 10.13 Adjusting the fork air pressure
- 10.14 Adjusting the compression damping of the fork
- 10.15 Adjusting the rebound damping of the fork
- 10.16 Handlebar position
- 10.17 Adjusting the handlebar position
11 SERVICE WORK ON THE CHASSIS
- 11.1 Raising the motorcycle with a lift stand
- 11.2 Removing the motorcycle from the lift stand
- 11.3 Bleeding the fork legs
- 11.4 Cleaning the dust boots of the fork legs
- 11.5 Removing the fork legs
- 11.6 Installing the fork legs
- 11.7 Removing the fork protector
- 11.8 Installing the fork protector
- 11.9 Removing the lower triple clamp
- 11.10 Installing the lower triple clamp
- 11.11 Checking steering head bearing play
- 11.12 Adjusting steering head bearing play
- 11.13 Lubricating the steering head bearing
- 11.14 Removing the start number plate
- 11.15 Installing the start number plate
- 11.16 Removing front fender
- 11.17 Installing front fender
- 11.18 Removing the shock absorber
- 11.19 Installing the shock absorber
- 11.20 Removing the seat
- 11.21 Mounting the seat
- 11.22 Removing the air filter box cover
- 11.23 Installing the air filter box cover
- 11.24 Removing the air filter
- 11.25 Cleaning the air filter and air filter box
- 11.26 Installing the air filter
- 11.27 Preparing air filter box cover for securing
- 11.28 Removing the main silencer
- 11.29 Installing the main silencer
- 11.30 Changing the glass fiber yarn filling in the main silencer
- 11.31 Removing the fuel tank
- 11.32 Installing the fuel tank
- 11.33 Checking the chain for dirt
- 11.34 Cleaning the chain
- 11.35 Checking the chain tension
- 11.36 Adjusting the chain tension
- 11.37 Checking the chain, rear sprocket, engine sprocket, and chain guide
- 11.38 Checking the frame
- 11.39 Checking the link fork
- 11.40 Checking throttle cable routing
- 11.41 Checking the rubber grip
- 11.42 Adjusting the basic position of the clutch lever
- 11.43 Checking/correcting the fluid level of the hydraulic clutch
- 11.44 Changing the hydraulic clutch fluid
12 BRAKE SYSTEM
- 12.1 Checking the free travel of the hand brake lever
- 12.2 Adjusting the basic position of the hand brake lever
- 12.3 Checking the brake discs
- 12.4 Checking the front brake fluid level
- 12.5 Adding front brake fluid
- 12.6 Checking the front brake linings
- 12.7 Changing the front brake linings
- 12.8 Checking the free travel of foot brake lever
- 12.9 Adjusting the basic position of the foot brake lever
- 12.10 Checking the rear brake fluid level
- 12.11 Adding rear brake fluid
- 12.12 Checking the brake linings of the rear brake
- 12.13 Changing the rear brake linings
13 WHEELS, TIRES
- 13.1 Removing the front wheel
- 13.2 Installing the front wheel
- 13.3 Removing the rear wheel
- 13.4 Installing the rear wheel
- 13.5 Checking the tire condition
- 13.6 Checking tire pressure
- 13.7 Checking spoke tension
14 COOLING SYSTEM
- 14.1 Cooling system
- 14.2 Radiator cover
- 14.3 Installing the radiator cover
- 14.4 Removing the radiator cover
- 14.5 Checking the antifreeze and coolant level
- 14.6 Checking the coolant level
- 14.7 Draining the coolant
- 14.8 Refilling with coolant
15 TUNING THE ENGINE
- 15.1 Checking throttle cable play
- 15.2 Adjusting throttle cable play
- 15.3 Carburetor tuning
- 15.4 Carburetor idle setting
- 15.5 Carburetor - adjusting the idle speed
- 15.6 Plug-in connector of ignition timing map adjustment
- 15.7 Changing the ignition timing map
- 15.8 Checking the basic position of the shift lever
- 15.9 Adjusting the basic position of the shift lever
16 SERVICE WORK ON THE ENGINE
- 16.1 Emptying the carburetor float chamber
- 16.2 Checking the gear oil level
- 16.3 Changing the gear oil
- 16.4 Adding the gear oil
17 CLEANING, CARE
- 17.1 Cleaning the motorcycle
18 STORAGE
- 18.1 Storage
- 18.2 Preparing for use after storage
19 TROUBLESHOOTING
20 TECHNICAL DATA
- 20.1 Engine
  - 20.1.1 All 125 models
  - 20.1.2 All 150 models
- 20.2 Engine tightening torques
- 20.3 Carburetor
  - 20.3.1 All 125 models
  - 20.3.2 Carburetor tuning (All 125 models)
  - 20.3.3 Carburetor - basic setting for sandy surfaces (All 125 models)
  - 20.3.4 All 150 models
  - 20.3.5 Carburetor tuning (All 150 models)
  - 20.3.6 Basic carburetor setting for sandy surfaces (All 150 models)
- 20.4 Capacities
  - 20.4.1 Gear oil
  - 20.4.2 Coolant
  - 20.4.3 Fuel
- 20.5 Chassis
- 20.6 Tires
- 20.7 Fork
  - 20.7.1 125/150 SX EU
  - 20.7.2 125/150 SX US
- 20.8 Shock absorber
  - 20.8.1 125/150 SX EU
  - 20.8.2 125/150 SX US
- 20.9 Chassis tightening torques
21 SUBSTANCES
22 AUXILIARY SUBSTANCES
23 STANDARDS
24 LIST OF ABBREVIATIONS
INDEX
- A
- B
- C
- D
- E
- F
- G
- H
- I
- K
- L
- M
- O
- P
- R
- S
- T
- U
- V
- W

KTM SX 125 2020 Owner's Manual

Pages 139

Year 2020

Language(s)

of 139

KTM SX 125 2020 Motorcycle Specification

The KTM SX 125 2020 is a high-performance motocross bike engineered for competitive racing and advanced off-road capabilities. Featuring a lightweight yet robust chrome-molybdenum steel frame, this motorcycle ensures superior agility and durability. The heart of the KTM SX 125 is its 124.8cc single-cylinder, two-stroke engine, which incorporates KTM’s advanced Transfer Port Injection (TPI) technology, providing consistent power delivery, improved fuel efficiency, and reduced emissions. The engine is paired with a 6-speed transmission system and a multi-plate clutch, facilitating smooth and precise gear shifts.

The bike is equipped with a WP XACT front fork and WP XACT rear shock absorber, both fully adjustable and designed to offer exceptional handling and stability on diverse terrains. The front suspension features 48 mm USD air-sprung forks, while the rear suspension utilizes a linkage system for enhanced shock absorption and rider comfort. Braking is managed by high-performance Brembo brakes, ensuring reliable stopping power with a 260 mm disc at the front and a 220 mm disc at the rear.

The KTM SX 125 2020 also boasts a lightweight, ergonomically optimized bodywork, designed to offer maximum rider comfort and control. The seat height stands at 950 mm, and the ground clearance is 375 mm, making it suitable for various track conditions. The fuel tank capacity is 7.5 liters, allowing for extended riding sessions without frequent refueling. The bike's overall weight, including fuel, is approximately 87.5 kg, contributing to its nimble handling and quick responsiveness. With its cutting-edge technology and racing-oriented design, the KTM SX 125 2020 is a top choice for riders seeking competitive performance and reliability in a motocross motorcycle.

KTM SX 125 2020 Motorcycle F.A.Q.

What is the recommended break-in procedure for a KTM SX 125 2020 motorcycle?

To properly break-in your KTM SX 125 2020, follow these steps: - During the first 1-2 hours of riding, avoid full throttle and excessive RPMs. - Gradually increase throttle and RPMs over the next several hours. - Change the transmission oil after the first 5-10 hours of riding. - Regularly check and tighten bolts and nuts during the break-in period.

How do I adjust the suspension settings on my KTM SX 125 2020?

To adjust the suspension on the KTM SX 125 2020: - Locate the compression and rebound adjusters on the forks and shock. - Use a screwdriver to turn the adjusters: clockwise for firmer settings, counterclockwise for softer settings. - Adjust to personal preference and terrain conditions, starting with manufacturer recommended settings.

What is the procedure for cleaning the air filter on a KTM SX 125 2020?

To clean the air filter: - Remove the seat and the filter cover. - Take out the air filter carefully to avoid debris falling into the intake. - Wash the filter with a mild soap solution and let it dry completely. - Apply air filter oil evenly and reinstall the filter.

How can I troubleshoot starting issues with my KTM SX 125 2020?

If your KTM SX 125 2020 won't start: - Check the fuel supply and ensure there's enough fuel. - Inspect the spark plug for fouling and proper gap. - Verify that the kill switch is in the 'Run' position. - Ensure the carburetor is clean and properly adjusted.

What regular maintenance tasks should be performed on a KTM SX 125 2020?

Regular maintenance tasks include: - Checking and cleaning the air filter. - Inspecting and adjusting the chain tension. - Changing the transmission oil every 10-15 hours of riding. - Inspecting brake pads and fluid levels.

How do I properly store my KTM SX 125 2020 for the winter?

For winter storage: - Clean the motorcycle thoroughly to prevent corrosion. - Drain the fuel tank or add a fuel stabilizer. - Remove the battery and keep it charged. - Store the bike in a dry, covered area to protect it from the elements.

What should I do if my KTM SX 125 2020 overheats?

If the bike overheats: - Immediately shut off the engine and allow it to cool. - Check the coolant level and top off if necessary. - Inspect the radiator for blockages or damage. - Verify that the cooling fan (if equipped) is operational.

How can I improve the performance of my KTM SX 125 2020?

To enhance performance: - Regularly maintain the air filter and exhaust system. - Consider upgrading the carburetor or exhaust for better airflow. - Adjust the suspension settings for optimal handling. - Use high-quality two-stroke oil and fuel for better engine performance.

What tire pressure is recommended for the KTM SX 125 2020?

The recommended tire pressure for the KTM SX 125 2020 is usually between 12-15 psi for off-road conditions. - Adjust the pressure based on terrain and rider preference for optimal grip and handling.

How do I replace the spark plug on a KTM SX 125 2020?

To replace the spark plug: - Remove the spark plug cap and unscrew the old plug using a spark plug wrench. - Check the gap on the new spark plug and adjust if necessary. - Install the new plug by hand to avoid cross-threading, then tighten with the wrench. - Reattach the spark plug cap securely.