KTM 125 DUKE 2021 User Manual

12 SERVICE WORK ON THE CHASSIS
120
12.7 Mounting the passenger seat
H01992-01
–
Attach hooks
1
on the passenger seat to seat mounting
2
on the subframe, and lower it at the rear while pushing for-
ward.
– Press the passenger seat downward until it clicks into place.
Warning
Danger of accidents The seat can come loose from the
anchoring if it is not mounted correctly.
– After assembly, check whether the seat is correctly
locked and cannot be pulled up.
– Finally, check that the passenger seat is correctly mounted.
12.8 Removing the front rider's seat
Preparatory work
– Remove the passenger seat. ( p. 119)

KTM 125 DUKE 2021 Specifications

General

Displacement	124.7 cc
Bore x Stroke	58 mm x 47.2 mm
Compression Ratio	12.5:1
Transmission	6-speed
Rear Suspension	WP APEX Monoshock
Front Brake	Four-piston radial fixed caliper, brake disc
Rear Brake	Single-piston floating caliper, brake disc
Front Tire	110/70 R17
Rear Tire	150/60 R17
Seat Height	830 mm
Dry Weight	139 kg
Frame	Steel Trellis Frame, Powder Coated
Ground Clearance	175 mm
Engine Type	Single Cylinder, 4-Stroke, Liquid Cooled
Torque	12 Nm
Fuel System	Electronic Fuel Injection
Front Suspension	WP APEX 43
Fuel Tank Capacity	13.4 liters
Wheelbase	1, 357 mm

Summary

Safety Advice

General Safety Guidelines

Covers proper use, misuse, and general safety instructions.

Risk and Symbol Definitions

Operational Safety Warnings

Details warnings related to tampering and safe operation.

Controls

Handlebar Levers and Throttle

Introduces clutch lever, hand brake lever, and throttle grip.

Left Handlebar Switch Layout

Identifies controls on the left side of the handlebar including lights.

Right Handlebar Controls and Safety Switch

Covers horn, emergency OFF switch, and start button operations.

Shift Lever and Side Stand

Braking and Parking Controls

Dash

Combination Instrument Overview

Describes the dash display, indicator lamps, and activation.

Display Modes and Information

Covers day-night mode, speed, ODO, and other display features.

Warning Indicators and System Status

Explains various indicator lamps and warning signals for vehicle status.

Instrument Display Layout

Details the layout and elements shown on the main instrument display.

Speed and Shift Warning Light

Information on speed display and the shift warning light function.

ODO and Coolant Temperature Displays

Fuel Level and Time Displays

Favourites and Quick Selector Displays

Menu Navigation and Customization

Details menu access, settings, and preferences.

Preparing for Use

First Use Preparation and Safety

Advice for preparing the motorcycle for initial operation and safety.

Engine Running-in and Loading

Riding Instructions

Pre-Ride Checks and Safety

Essential checks before riding for roadworthiness and safety.

Starting the Engine Safely

Procedures for starting the motorcycle and associated safety.

Riding and Shifting Techniques

Guidance on shifting gears, riding, and handling the vehicle.

Braking System Operation

Instructions and warnings on applying brakes effectively.

Stopping and Parking Procedures

Refueling Procedures and Safety

Service Schedule

Required Maintenance Tasks

Tuning the Chassis

Shock Absorber Spring Preload Adjustment

Brake System

Anti-lock Braking System (ABS) Overview

Explains ABS components, function, and warnings.

Brake Disc Inspection

Front Brake Fluid Level and Maintenance

Rear Brake Fluid Level and Maintenance

Rear Brake Lining Inspection

Wheels and Tires

Front Wheel Removal and Installation

Rear Wheel Removal and Installation

Tire Condition and Wear Check

Tire Pressure Check and Adjustment

Correct tire pressure for solo and passenger riding.

Electrical System

12-V Battery Service

Fuse Management

Changing main, ABS, and individual electrical fuses.

Headlight Setting and Adjustment

Service Work on the Engine

Engine Oil Level Check

Procedure for checking engine oil level when the engine is warm.

Engine Oil and Filter Change

Steps for changing engine oil, oil filter, and oil screen.

Adding Engine Oil

Troubleshooting

Engine and Starting Faults

Diagnosing and resolving common engine starting and running issues.

Electrical System Faults

Diagnosing and resolving electrical system problems.

Technical Data

Engine Specifications

Detailed technical data for the engine components and performance.

Engine Tightening Torques

Specific torque values for engine fasteners and components.

Capacities and Fluids

Chassis and Suspension Specifications

Electrical System Specifications

Tire Specifications

Chassis Tightening Torques