KTM 250 SX US 2015 User Manual (English)

Questions and Answers:

A
Anna LopezAug 17, 2025
How to fix KTM 250 SX US 2015 Motorcycle engine that does not speed up?
- J
  Jeffrey LopezAug 17, 2025
  If your KTM Motorcycle engine does not speed up, the carburetor might be running over due to a dirty or worn float needle, or the carburetor jets might be loose; check and set the carburetor components. Inspect the fuel tank breather and clean the fuel tap if the fuel feed is interrupted. Clean the air filter and air filter box if the air filter is very dirty. Check the exhaust system for damage and replace the glass fiber yarn filling of the main silencer if necessary. Finally, check the ignition system for any faults.
A
Ashley GallegosAug 21, 2025
What to do if KTM 250 SX US 2015 engine stalls?
- H
  Hayley PeckAug 21, 2025
  If your KTM Motorcycle engine stalls or pops into the carburetor, it might be due to a lack of fuel; turn the fuel tap to the ON position and refuel. Check the intake flange and carburetor for tightness if the engine is taking in bad air. Clean the connector and treat it with contact spray if it is loose or oxidized.
J
Janet ProctorAug 25, 2025
Why KTM 250 SX US 2015 engine cannot be cranked?
- M
  Michelle LeonAug 25, 2025
  If your KTM Motorcycle engine cannot be cranked, it might be due to an operating error; ensure you follow the correct starting procedure. Another potential cause is a discharged battery, in which case you should recharge the battery and check the charging voltage, closed current, and alternator. Additionally, inspect the main fuse, starter relay, and starter motor for any faults.
C
cervantesbrianAug 27, 2025
Why is my KTM 250 SX US 2015 Motorcycle engine overheating?
- J
  Joshua VincentAug 27, 2025
  If your KTM Motorcycle engine overheats, check the coolant level and look for any leaks in the cooling system. Ensure there's sufficient air stream and switch off the engine when stationary. Clean the radiator fins if they are dirty. If there's foam formation in the cooling system, drain and refill the coolant. Inspect the cylinder head and cylinder head gasket for damage. Replace any bent radiator hoses and adjust the ignition if the stator is loose.
K
Kimberly HarperAug 30, 2025
Why KTM 250 SX US 2015 Motorcycle engine has no idle?
- G
  gordonwilliamAug 31, 2025
  If your KTM Motorcycle engine has no idle, the idling jet might be blocked; check and set the carburetor components. Adjust the idle speed if the adjusting screws on the carburetor are distorted. Change the spark plug if it is defective. Check the ignition coil and spark plug connector if the ignition system is defective.
M
Mark GreeneSep 3, 2025
Why does KTM 250 SX US 2015 Motorcycle emit white smoke?
- J
  jrichardsonSep 3, 2025
  If you see white smoke (steam) in the exhaust gas of your KTM Motorcycle, it could be due to a damaged cylinder head or cylinder head gasket; check these components.
J
Julia JohnsonSep 6, 2025
Why gear oil exits at the vent hose in KTM 250 SX US 2015 Motorcycle?
- D
  Danielle WilsonSep 6, 2025
  If gear oil is exiting at the vent hose of your KTM Motorcycle, it may be because too much gear oil was added. Check the gear oil level.
S
Samantha FloydSep 9, 2025
How to fix water in the gear oil of KTM Motorcycle?
- S
  Stephanie HillSep 10, 2025
  If there is water in the gear oil of your KTM Motorcycle, it could be due to a damaged shaft seal ring or water pump; check these components.

KTM 250 SX US 2015 Specifications

General

Brand	KTM
Model	250 SX US 2015
Category	Motorcycle
Language	English

Summary

Dear KTM Customer

Means of Representation

Symbols Used in Manual

Explanation of symbols used throughout the owner's manual for clarity and safety.

Typographical Formats Used

Explanation of typographical formats used in the document for proprietary and brand names.

Safety Advice and Precautions

Intended Use of Motorcycle

Defines the intended use for SX and XC models, specifying offroad competition and avoiding public roads.

General Safety Instructions

Highlights the importance of reading safety instructions and adhering to vehicle warning labels.

Understanding Risk Levels and Symbols

Defines danger, warning, caution, and note levels with associated symbols for risk assessment.

Warning Against Tampering with Noise Control

Details prohibited acts related to noise control systems and consequences of tampering.

Safe Operation Guidelines

Importance of Protective Clothing

Emphasizes wearing appropriate protective gear for riding to minimize injury risk.

Workshop Work Rules and Tool Usage

Outlines rules for workshop procedures, including use of special tools and part replacement.

Environmental Responsibility and Disposal

Discusses legal requirements for motorcycle use and responsible disposal of fluids and components.

Owner's Manual Guidance

Stresses the importance of reading the manual for operation, maintenance, and safety information.

Important Information and Recommendations

Warranty Terms and Conditions

Details warranty voidance due to unauthorized work and references the Service & Warranty Booklet.

Approved Operating Fluids and Substances

Specifies using approved fluids and lubricants, with a warning about environmental hazards of fuel.

Using Approved Spare Parts and Accessories

Recommends using KTM-approved parts for safety and liability, and lists sources for PowerParts.

Service and Maintenance Importance

Highlights the necessity of correct service, care, and tuning for optimal operation and wear prevention.

Notes on Manual Illustrations

Informs that manual figures may show special equipment and not always exact component views.

KTM Customer Service and Dealer Network

Directs customers to authorized dealers for questions and provides the international KTM website.

Vehicle Component Identification

Left Front View of Motorcycle

Diagram identifying key components visible from the left front of the motorcycle.

Rear Right View of Motorcycle

Diagram identifying key components visible from the rear right of the motorcycle.

Locating Vehicle Serial and Identification Numbers

Chassis Number Location

Shows the location of the chassis number stamped on the steering head.

Type Label Location

Indicates the position of the type label, fixed to the front of the steering head.

Engine Number Location

Details the location of the engine number stamped on the left side of the engine.

Fork Part Number Location

Shows where the fork part number is stamped on the inner side of the fork stub.

Shock Absorber Part Number Location

Indicates the location of the shock absorber part number on the top of the shock absorber.

Motorcycle Controls and Functions

Clutch Lever Operation

Explains the function and location of the clutch lever for 125/150 SX and 250/300 models.

Front Brake Lever Operation

Describes the location and function of the hand brake lever for activating the front brake.

Throttle Grip Operation

Identifies the location of the throttle grip on the right side of the handlebar.

Kill Switch Functionality

Explains the location and two states of the kill switch for engine operation.

XC Model Electric Starter Button

Opening the Fuel Tank Filler Cap

Provides instructions and safety warnings for opening the fuel tank filler cap.

SX Model Fuel Tap Operation

Closing the Fuel Tank Filler Cap

Instructions for properly closing the fuel tank filler cap on SX and XC models.

Choke Lever Functionality

XC Model Fuel Tap Operation

Describes the function and states (OFF, ON, RES) of the fuel tap on XC models.

Shift Lever and Gear Positions

Identifies the shift lever location and shows gear positions for SX and XC models.

Kick Starter Operation

Rear Brake Lever Operation

Identifies the foot brake lever location for activating the rear brake.

SX Model Plug-in Stand Usage

Explains the purpose and usage of the plug-in stand for parking SX models.

XC Model Side Stand Usage

Describes the location and usage of the side stand for parking XC models.

Preparing Motorcycle for Use

Initial Use and Pre-Ride Checks

Provides essential advice for first use, including safety, controls familiarization, and handling adjustments.

Engine Running-In Procedure

Preparing for Difficult Riding Conditions

Outlines preparations for various challenging terrains and conditions, including air filter and electrical checks.

Dry Sand Riding Preparations

Covers checks like radiator cap and air filter modifications for riding on dry sand.

Wet Sand Riding Preparations

Wet/Muddy Surface Riding Preparations

Outlines preparations for wet and muddy conditions, including air filter covers and sprocket changes.

High Temp/Low Speed Riding Preparations

Covers preparations for high temperatures and low speeds, including radiator cap and secondary ratio adjustments.

Low Temp/Snow Riding Preparations

Riding Instructions and Checks

Pre-Ride Checks and Maintenance

Lists essential checks before riding, covering fluids, brakes, chain, controls, and general tightness.

Engine Starting Procedure

Provides steps for starting the engine, including fuel tap, choke, and kick/electric starter usage.

Gear Shifting and Riding Techniques

Braking Techniques and Warnings

Covers braking principles, dangers of locking wheels, and checks for brake system efficiency.

Stopping and Parking Procedures

Motorcycle Transport Guidelines

Provides notes on safe transport, emphasizing securing the vehicle and avoiding damage.

Refueling the Motorcycle Safely

Scheduled Maintenance Service

SX Model Service Schedule

Lists periodic maintenance tasks for SX models based on operating hours and fuel consumption.

Additional SX Service Work

Details service tasks that are performed as additional orders, categorized by intervals.

XC Model Service Schedule

Lists periodic maintenance tasks for XC models based on operating hours and fuel consumption.

Additional XC Service Work

Chassis Tuning and Suspension Adjustment

Basic Chassis Setting for Rider Weight

Explains how to adjust suspension settings based on rider weight for optimal motorcycle characteristics.

Shock Absorber Compression Damping

Describes the division of shock absorber compression damping into high-speed and low-speed ranges.

Adjusting Low-Speed Shock Compression Damping

Provides steps to adjust the low-speed compression damping of the shock absorber.

Shock Absorber Rebound Damping Adjustment

Measuring Unloaded Rear Wheel Sag

Procedure for measuring the unloaded sag of the rear wheel as a preliminary step.

Checking Static Shock Absorber Sag

Details how to check the static sag of the shock absorber and adjust spring preload if needed.

Checking Riding Shock Absorber Sag

Explains how to measure riding sag with the rider on the motorcycle for proper suspension setup.

Adjusting Shock Absorber Spring Preload

Adjusting Riding Sag of Shock Absorber

Procedure for adjusting the riding sag, which may involve changing spring rate or preload.

Checking Basic Fork Suspension Settings

Adjusting Fork Compression Damping

Adjusting Fork Rebound Damping

Provides instructions for adjusting fork rebound damping for various models and comfort settings.

Handlebar Position Adjustment Options

Procedure for Adjusting Handlebar Position

Details the steps for adjusting handlebar position, including loosening clamps and tightening screws.

Chassis Service and Maintenance Procedures

Raising Motorcycle with Lift Stand

Describes the procedure for safely raising the motorcycle using a lift stand, ensuring stability.

Removing Motorcycle from Lift Stand

Details the steps for safely removing the motorcycle from the lift stand, including using stands.

Bleeding Fork Legs

Provides instructions for bleeding the fork legs to release excess pressure.

Removing Front Fork Legs

Cleaning Fork Leg Dust Boots

Explains the importance and method for cleaning fork leg dust boots to prevent oil seal leaks.

Installing Front Fork Legs

Removing Front Fork Protectors

Instructions for removing the fork protectors, including screws and clamps.

Installing Front Fork Protectors

Provides steps for installing the fork protectors, including mounting and tightening screws.

Removing Lower Triple Clamp

Installing Lower Triple Clamp

Details the procedure for installing the lower triple clamp, cleaning bearings, and positioning seals.

Checking Steering Head Bearing Play

Adjusting Steering Head Bearing Play

Greasing Steering Head Bearing

Provides instructions for greasing the steering head bearing, referencing lower triple clamp removal.

Removing Front Number Plate

Details the procedure for removing the start number plate, including screws and clamps.

Installing Front Fender

Installing Front Number Plate

Instructions for installing the front number plate, ensuring holding lugs engage correctly.

Removing Front Fender

Step-by-step guide for removing the front fender, including screws.

Removing Rear Shock Absorber

Installing Rear Shock Absorber

Details the procedure for installing the shock absorber and tightening related hardware.

Removing Motorcycle Seat

Installing Motorcycle Seat

Details how to correctly mount the seat, hooking the front and securing it.

Removing Air Filter Box Lid

Provides steps to remove the air filter box lid by removing screws.

Removing Air Filter

Installing Air Filter Box Lid

Instructions for installing the air filter box lid, ensuring proper fitment and screw tightening.

Cleaning Air Filter and Air Filter Box

Explains how to clean the air filter and box, with warnings about cleaning agents and environmental hazards.

Installing Clean Air Filter

Securing Air Filter Box Lid

Details how to drill a hole and secure the air filter box lid, likely for specific conditions.

Removing Exhaust Main Silencer

Sealing the Air Filter Box

Instructions for sealing the air filter box in a marked area, likely for dust/water protection.

Installing Exhaust Main Silencer

Details how to install the main silencer, including mounting and tightening screws.

Changing Main Silencer Glass Fiber Filling

Explains how to change the glass fiber filling in the main silencer, noting performance changes.

Removing Fuel Tank

Installing Fuel Tank

Checking Chain for Dirt and Wear

Cleaning and Lubricating the Chain

Explains how to clean and lubricate the chain for optimal service life, with safety warnings.

Checking Chain Tension

Adjusting Chain Tension

Step-by-step guide for adjusting chain tension using adjusting screws and checking alignment.

Checking Chain and Sprockets for Wear

Checking Frame for Damage

Checking Chain Guides and Tensioners

Focuses on checking chain sliding pieces and guides for wear and tightness.

Checking Swingarm for Damage

Checking Throttle Cable Routing

Explains how to check the routing of the throttle cable for proper function on different models.

Checking Handlebar Rubber Grips

Securing Handlebar Rubber Grips

Details how to secure rubber grips using wire for added safety and durability.

Adjusting Clutch Lever Position

Explains how to adjust the clutch lever position to suit hand size for better control.

Checking Hydraulic Clutch Fluid Level

Changing Hydraulic Clutch Fluid

Step-by-step guide for changing the hydraulic clutch fluid, including bleeding the system.

Brake System Maintenance and Checks

Checking Front Brake Lever Free Travel

Explains how to check front brake lever free travel and the importance of proper adjustment.

Adjusting Front Brake Lever Position

Details how to adjust the basic position of the hand brake lever for optimal reach and free travel.

Checking Brake Disc Thickness and Condition

Covers checking brake disc thickness against wear limits and for damage or deformation.

Adding Front Brake Fluid

Checking Front Brake Fluid Level

Provides instructions for checking the front brake fluid level and adding fluid if necessary.

Changing Front Brake Linings

Checking Front Brake Linings

Explains how to check front brake lining minimum thickness and for damage or cracking.

Checking Rear Brake Lever Free Travel

Adjusting Rear Brake Lever Position

Details how to adjust the basic position of the foot brake lever for optimal reach and free travel.

Adding Rear Brake Fluid

Checking Rear Brake Fluid Level

Provides instructions for checking the rear brake fluid level and adding fluid if necessary.

Changing Rear Brake Linings

Checking Rear Brake Linings

Explains how to check rear brake lining minimum thickness and for damage or cracking.

Wheels and Tires Maintenance

Removing Front Wheel

Step-by-step guide for removing the front wheel, including brake caliper and spindle.

Installing Front Wheel

Details the procedure for installing the front wheel, checking bearings, and greasing seals.

Checking Tire Condition and Wear

Removing Rear Wheel

Step-by-step guide for removing the rear wheel, including chain adjuster and spindle.

Installing Rear Wheel

Details the procedure for installing the rear wheel, checking bearings, chain tension, and alignment.

Checking Tire Air Pressure

Checking Spoke Tension

Details how to check spoke tension and the importance of correct tension for wheel balance and integrity.

Electrical System Maintenance

Removing XC Model Battery

Step-by-step guide for removing the battery from XC models, with safety warnings about acid.

Installing XC Model Battery

Details the procedure for installing the battery in XC models, including terminal connections and securing.

Recharging XC Model Battery

Changing XC Model Main Fuse

Details how to change the main fuse, located in the starter relay housing, for XC models.

Cooling System Operation and Maintenance

Overview of Cooling System

Describes how the water pump circulates coolant and how the radiator cap regulates pressure.

SX Model Radiator Cover Installation

Explains the function and installation options for radiator covers based on ambient temperature.

Installing SX Model Radiator Cover

Details the steps for installing the radiator cover, including detaching the radiator shield.

Checking Coolant Antifreeze and Level

Removing SX Model Radiator Cover

Provides instructions for removing the radiator cover and radiator shield.

Draining Engine Coolant

Checking Radiator Coolant Level

Explains how to check the coolant level in the radiator and correct it if necessary.

Refilling Engine Coolant

Engine Tuning and Adjustments

Checking Throttle Cable Play

Explains how to check throttle cable play and its effect on throttle response and idle speed.

Adjusting Throttle Cable Play

Details the procedure for adjusting throttle cable play using barrel adjusters and nuts.

Carburetor Idle Speed Settings

Explains the importance of idle settings for starting, stability, and throttle response, detailing ranges.

Emptying Carburetor Float Chamber

Adjusting Carburetor Idle Speed

Provides steps for adjusting idle speed using the idle air adjusting screw for optimal engine operation.

Ignition Timing Map and Plug-in Connection

Changing Engine Ignition Curve

Describes how to change the ignition curve by connecting or disconnecting the plug-in connection.

Checking Basic Shift Lever Position

Explains how to check the distance between the boot and shift lever for proper positioning.

Engine Characteristic: Auxiliary Spring (250/300 Models)

Adjusting Basic Shift Lever Position

Details the procedure for adjusting the shift lever position for optimal ergonomics and control.

Setting Auxiliary Spring for Engine Characteristic

Provides instructions for setting the auxiliary spring to alter engine performance characteristics.

Engine Service and Maintenance

Checking Engine Gear Oil Level

Explains how to check the gear oil level while the engine is cold and how to add oil if needed.

Changing Engine Gear Oil

Details the process of draining and refilling the engine gear oil.

Draining Engine Gear Oil

Refilling Engine Gear Oil

Details the procedure for refilling the engine gear oil, including oil type and quantity.

Adding Engine Gear Oil

Motorcycle Cleaning and Care

Motorcycle Storage Procedures

Preparing Motorcycle for Long-Term Storage

Outlines actions for long-term storage, including fuel additive, cleaning, and fluid checks.

Preparing Motorcycle for Use After Storage

Details the steps to take when preparing the motorcycle for use after a storage period, including checks.

Technical Specifications and Data

Engine Technical Data

Provides detailed specifications for the engine, including bore, stroke, transmission, and ignition.

Engine Tightening Torque Specifications

Lists torque specifications for various engine screws and nuts, essential for proper assembly.

Carburetor Specifications

Provides detailed specifications for carburetor types, jet settings, and idle adjustments.

Technical Capacities: Fluids and Fuel

Lists capacities for gear oil, coolant, and fuel tank, including reserve for XC models.

Chassis Specifications

Provides details on frame, fork, suspension travel, shock absorber, brakes, and tire pressure.

Fork Specifications and Tuning

Lists fork part numbers, compression/rebound damping settings, spring rates, and oil capacities.

Shock Absorber Specifications and Tuning

Provides shock absorber part numbers, damping settings, spring preload, and spring rates.

XC Model Shock Absorber Specifications and Tuning

Lists shock absorber specifications for XC models, including damping, preload, and spring rates.

Chassis Tightening Torque Specifications

Lists torque specifications for various chassis screws and nuts, essential for safe assembly.

Recommended Fluids and Substances

2-Stroke Engine Oil Specifications

Details 2-stroke engine oil classifications, guidelines, and recommended suppliers.

Brake Fluid Specifications

Specifies DOT 4/5.1 brake fluid requirements, guidelines, and recommended suppliers.

Coolant Specifications and Mixture Ratio

Details coolant requirements, mixture ratios for antifreeze protection, and recommended types.

Engine Oil (15W/50) Specifications

Provides specifications for 15W/50 engine oil, including JASO and SAE classifications.

Fork Oil (SAE 4) Specifications

Lists specifications for SAE 4 fork oil, essential for suspension maintenance.

Hydraulic Fluid (ISO VG 15) Specifications

Specifies ISO VG 15 hydraulic fluid requirements and recommended suppliers.

Shock Absorber Fluid (SAE 2.5) Specifications

Lists specifications for SAE 2.5 shock absorber fluid and recommended suppliers.

Super Unleaded Fuel (ROZ 98) Requirements

Details requirements for super unleaded fuel, including standard compliance and ethanol content.

Super Unleaded Fuel (ROZ 95) Requirements

Specifies requirements for super unleaded fuel (95 octane), including mixture ratios and ethanol content.

Auxiliary Substances and Recommended Products

Air Filter Cleaner Product

Recommends specific air filter cleaner products for effective cleaning.

Chain Cleaner Product

Recommends specific chain cleaner products for drivetrain maintenance.

Fuel Additive Product

Recommends fuel additive products for stabilizing fuel during storage.

High Viscosity Grease Product

Recommends specific high viscosity grease for lubrication points.

Long-Life Grease Product

Recommends specific long-life grease for lubrication applications.

Motorcycle Cleaner Product

Recommends specific motorcycle cleaner products for vehicle upkeep.

Off-Road Chain Spray Product

Recommends specific off-road chain spray for drivetrain lubrication.

Foam Air Filter Oil Product

Recommends specific oil for foam air filters to ensure proper filtration.

Paint, Metal, and Rubber Preservative Products

Recommends products for preserving paint, metal, and rubber components.

Rubber Grip Adhesive Product

Recommends specific rubber grip adhesive for securing grips.

Special Cleaner for Surfaces

Recommends special cleaners for glossy/matte finishes, metal, and plastic surfaces.

Universal Oil Spray Product

Industry Standards and Classifications

JASO FC Standard for 2-Stroke Oils

Explains the JASO FC classification for 2-stroke engine oils, emphasizing racing performance.

JASO T903 MA Standard for 4-Stroke Motorcycle Oils

Details the JASO T903 MA standard for 4-stroke motorcycle oils, covering gearbox and clutch lubrication.

SAE Viscosity Classification System

Explains the SAE classification system for oils based on viscosity, not quality.

Related product manuals

KTM 250 SX-F USA 2010