KTM 125 SX EU 2015 - User Manual

Questions and Answers

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William McneilAug 18, 2025
How to fix KTM Motorcycle engine that does not speed up?
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  Johnny SmithAug 18, 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.
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Heather FowlerAug 21, 2025
What to do if KTM Motorcycle engine stalls?
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  Dana RodriguezAug 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.
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daviskristyAug 25, 2025
Why KTM 125 SX EU 2015 engine cannot be cranked?
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  Eric SmallAug 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.
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Alan BrownAug 28, 2025
Why is my KTM 125 SX EU 2015 engine overheating?
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  Brian BeckAug 28, 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.
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angela06Aug 31, 2025
Why KTM Motorcycle engine has no idle?
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  zwrightAug 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.
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David MosesSep 3, 2025
Why does KTM 125 SX EU 2015 Motorcycle emit white smoke?
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  Mrs. Ashley BautistaSep 4, 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.
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Jason JohnsonSep 7, 2025
Why gear oil exits at the vent hose in KTM 125 SX EU 2015 Motorcycle?
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  Larry MooreSep 7, 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.
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pjarvisSep 10, 2025
How to fix water in the gear oil of KTM Motorcycle?
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  Juan MartinSep 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.
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Crystal ColemanNov 14, 2025
What to do if KTM 125 SX EU 2015 engine turns but does not start?
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  David MurphyNov 14, 2025
  If your KTM Motorcycle engine turns but doesn't start, the issue could stem from several factors. First, ensure you are following the correct starting procedure, in case it is an operating error. If the motorcycle has been out of use for a while, old fuel in the float chamber might be the cause; empty the carburetor float chamber. Check for any interruptions in the fuel feed by inspecting the fuel tank breather and cleaning the fuel tap. Also, make sure to check and set the carburetor components. Clean and dry the spark plug, or replace it if necessary. Adjust the plug gap to 0.60 mm (0.0236 in). Inspect the ignition system and kill switch for any faults. Clean the connector and treat it with contact spray if it is loose or oxidized. Finally, check for water in the carburetor or blocked je...