I have heard from a few people that filling tank only with hi octane causes valve leakages or damages insides of the engine or carbeurator.
How's that even logical or possible?
Because that fuel is the most clean form of cumbustion. Why would it harm a 110cc's engine.
My personal experience with both type of fuels.
Regular = smoother bike , lesser fuel average per litre , lesser acceleration and top speed time increased.
Hi octane = slight increase in vibration , higher fuel average per litre , faster acceleration and reduced top speed time.