A loss of power in a Honda CBR 250R at higher RPMs and speeds can be caused by several factors. Here are a few potential issues to consider:
Fuel System: A clogged fuel filter or a problem with the fuel injectors can result in insufficient fuel delivery at higher RPMs. This can lead to a loss of power. It's worth checking the fuel system components and ensuring they are clean and functioning properly.
Air Intake: A restricted air intake or a clogged air filter can limit the amount of air entering the engine, which can lead to power loss. Check the air filter for cleanliness and replace it if necessary. Also, inspect the air intake system for any blockages or restrictions.
Ignition System: Problems with the ignition system, such as faulty spark plugs or a malfunctioning ignition coil, can cause misfires and power loss. Make sure the spark plugs are in good condition and properly gapped. If necessary, consider replacing them. Additionally, have the ignition system components tested to ensure they are working correctly.
Exhaust System: A restricted or damaged exhaust system can create back pressure and reduce engine performance. Inspect the exhaust system for any blockages, leaks, or damage that could be affecting the flow of exhaust gases.
Engine Compression: A drop in engine compression can result in power loss. Low compression can be caused by various factors, including worn piston rings or valve seals. If other potential causes have been ruled out, it may be necessary to perform a compression test to check the engine's compression levels.
If the showroom was unable to identify the specific issue, you may consider seeking a second opinion from another reputable motorcycle mechanic or Honda service center. They may have additional expertise or diagnostic tools that can help pinpoint the problem. Providing them with detailed information about the symptoms and the steps you've already taken can assist them in diagnosing the issue more effectively.