Based on the information you've provided, it seems like there may be an issue with the electrical system of your Pulsar 135, specifically related to the self-start mechanism. While I can offer some general suggestions, it's important to note that diagnosing and repairing mechanical issues is best done by a qualified mechanic or technician who can inspect your bike in person. Here are a few things you could consider:
Battery Check: Start by checking the battery voltage and ensuring it has sufficient charge. A weak or faulty battery may not provide enough power to activate the self-start mechanism properly. If the battery is low, try charging it or replacing it if necessary.
Starter Motor: The self-start mechanism relies on a starter motor to turn the engine. If the starter motor is malfunctioning, it may not be generating enough power to start the bike. Have the starter motor checked by a professional to determine if it needs repair or replacement.
Ignition Switch: There could be a problem with the ignition switch or its wiring. Faulty wiring or a loose connection could prevent the spark from reaching the spark plug during self-start. Inspect the ignition switch and associated wiring for any signs of damage or loose connections.
Spark Plug and Ignition Coil: Although you mentioned seeing sparks in the spark plug during kick start, it's worth inspecting the spark plug and the ignition coil. Ensure that the spark plug is in good condition, properly gapped, and securely connected. The ignition coil should also be checked for any faults or damage.
Safety Interlock System: Some motorcycles have safety interlock systems that prevent the engine from starting unless certain conditions are met (e.g., the clutch lever is pulled in). Check if your Pulsar 135 has any such safety interlock system and ensure it is functioning correctly.
It's important to consult with a professional mechanic or authorized service center for a thorough diagnosis and repair of the issue. They will have the necessary expertise and diagnostic tools to identify the specific cause of the problem in your bike and provide the appropriate solution.