If your Yamaha FZS V2 FI version is experiencing starting issues and then stalling when you accelerate, there are a few possible causes and troubleshooting steps you can take:
Fuel-related issues: Ensure that there is sufficient fuel in the tank and that the fuel supply is reaching the engine properly. Check for any clogged fuel lines or a malfunctioning fuel pump. If necessary, clean or replace the fuel filter.
Ignition system: Inspect the spark plug and make sure it is clean and in good condition. If it appears worn out or damaged, replace it with a new one. Check the ignition coil and wiring connections for any loose or faulty connections. If necessary, consult a mechanic or refer to the owner's manual for specific instructions.
Air intake and carburetor: Check the air filter to ensure it is clean and not obstructed. If it's dirty, clean or replace it as needed. In case your bike has a carburetor, make sure it is properly adjusted and clean. Consider cleaning the carburetor jets and passages if they are clogged.
Battery and electrical system: Ensure that the battery is adequately charged and in good condition. Weak or faulty batteries can cause starting and stalling issues. Check the battery terminals for corrosion or loose connections and clean/tighten them if necessary.
Professional inspection: If the above steps do not resolve the issue, it might be best to have your motorcycle inspected by a qualified mechanic or authorized Yamaha service center. They have the expertise and diagnostic tools to identify and fix more complex issues.
Remember to refer to your motorcycle's owner's manual for specific maintenance procedures and troubleshooting tips. It's also a good idea to consult with a professional mechanic for a more accurate diagnosis and guidance tailored to your bike's specific model.