TECHNICAL SPECIFICATIONS

KTM 125 SX 2018 (UE)

2018–2018 125 SX (2018) EU

125 cc 2T

MotorDataBook

Key specifications

The essentials of this version at a glance.

1.85 US gal
Fuel tank capacity
✓
80/100 - 21 51M TT
Front tyre size
✓
100/90 - 19 57M TT
Rear tyre size
✓
Líquido refrigerante de alta calidad sin silicato con aditivo anticorrosión para motores de aluminio
Coolant specification
✓
1.27 US qt
Coolant capacity
✓
DOT 4 / DOT 5.1
Brake fluid specification
✓
JASO T903 MA
Transmission fluid specification
✓
2.17 in
Drive chain slack minimum
✓
1 items

Transmission & Drivetrain

Transmission fluid specification
JASO T903 MA ✓
Aceite del cambio (motor de 2 tiempos).
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 108 Verification: Verified Open document
1 items

Dimensions & Weights

Fuel tank capacity
1.85 US gal ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 103 Verification: Verified Open document
7 items

Brakes

Brake fluid specification
DOT 4 / DOT 5.1 ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 109 Verification: Verified Open document
Front brake disc diameter
10.24 in ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 103 Verification: Verified Open document
Front brake disc minimum thickness
0.1 in ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 103 Verification: Verified Open document
Rear brake disc diameter
8.66 in ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 103 Verification: Verified Open document
Rear brake disc minimum thickness
0.14 in ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 103 Verification: Verified Open document
Front brake pad minimum thickness
0.04 in ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 67 Verification: Verified Open document
Rear brake pad minimum thickness
0.04 in ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 72 Verification: Verified Open document
2 items

Wheels and tyres

Front tyre size
80/100 - 21 51M TT ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 104 Verification: Verified Open document
Rear tyre size
100/90 - 19 57M TT ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 104 Verification: Verified Open document
5 items

Motorcycle Specific

Drive chain size
5/8 x 1/4" ✓
Paso y ancho interior de la cadena en pulgadas, tal como los da el manual.
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 103 Verification: Verified Open document
Drive chain slack minimum
2.17 in ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 58 Verification: Verified Open document
Drive chain slack maximum
2.28 in ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 58 Verification: Verified Open document
Front axle torque
25.81 lb-ft ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 107 Verification: Verified Open document
Rear axle torque
59 lb-ft ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 107 Verification: Verified Open document
2 items

Engine & Fluids

Coolant specification
Líquido refrigerante de alta calidad sin silicato con aditivo anticorrosión para motores de aluminio ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 109 Verification: Verified Open document
Coolant capacity
1.27 US qt ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 103 Verification: Verified Open document
1 items

Filters & Service Parts

Spark plug gap
0.02 in ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 96 Verification: Verified Open document
2 items

Torque Specifications

Spark plug torque
18.44 lb-ft ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 98 Verification: Verified Open document
Front brake caliper torque
18.44 lb-ft ✓
Sources and verification (1)
Primary source ✓ Official Publisher: KTM Sportmotorcycle GmbH (buscador oficial de manuales) Document: 125 SX 2018 – Manual de instrucciones, UE en español (18_3213636_es_OM) Reference: PDF p. 106 Verification: Verified Open document

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MotorDataBook prioritises official documentation and shows conditions, notes and traceability whenever a figure needs context. Unconfirmed values should not be presented as facts.