If your 1999 Kawasaki Vulcan 800 motorcycle is running but won't start unless you bypass the starter solenoid by hitting both bolts, there could be several potential issues causing this problem. Here are a few possibilities:
Faulty starter solenoid: The starter solenoid is responsible for engaging the starter motor when you try to start the motorcycle. If the solenoid is faulty or worn out, it may not engage properly, preventing the starter motor from turning and starting the engine.
Loose or corroded electrical connections: Check the connections between the starter solenoid, battery, and starter motor. Loose or corroded connections can disrupt the flow of electrical current, leading to starting issues.
Weak battery: A weak or discharged battery may not have enough power to engage the starter motor and start the engine. Check the battery voltage and consider having it tested to ensure it is in good condition.
Faulty ignition switch: The ignition switch is responsible for activating the electrical system and engaging the starter circuit. If the ignition switch is faulty, it may not be sending the correct signals to the starter solenoid, resulting in starting problems.
Starter motor issues: The starter motor itself may be faulty, causing it to fail to engage properly and start the engine. A worn-out starter motor might require replacement or repairs.
It is recommended to consult a qualified motorcycle mechanic or technician to diagnose and repair the specific issue with your Kawasaki Vulcan 800. They will have the expertise and tools necessary to identify the problem accurately and provide the appropriate solution.