It seems like there might be some issues with the clutch or transmission on your Honda CBR 250R. Let's address each concern separately:
Revving more than accelerating: If you notice that the engine is revving high but the motorcycle is not accelerating as expected, it could indicate a slipping clutch. A slipping clutch occurs when the clutch plates fail to engage properly, resulting in power loss and poor acceleration. This issue needs to be addressed by a qualified mechanic. They will need to inspect and potentially replace the clutch plates if they are worn or damaged.
Downshifting without holding in the clutch: Downshifting without using the clutch is not normal and should not be done. The clutch is responsible for disengaging the engine from the transmission, allowing smooth gear changes. Shifting without using the clutch can cause excessive wear and damage to the transmission components. It's important to use the clutch when downshifting to ensure proper gear engagement and to avoid potential damage to the gearbox.
Given these issues, it is recommended that you take your Honda CBR 250R to a reputable motorcycle mechanic or authorized service center. They will be able to diagnose the problems accurately and provide the necessary repairs or adjustments to ensure your motorcycle is running properly and safely.