Kills me that people still use premium in engines that do not require it. And then they use "additive package" to justify it. IF you run a fuel filter(as you should) and IF you buy from a reputable station, then it takes a LONG time for an engine to get dirty where the additives matter.
Also, better stations use higher additive packs than lesser stations. For example, I fill at costco most of the time. Their regular is considered "top tier" fuel.
Top Tier Gasoline
Most cases where a person thinks their engine runs smoother is merely placebo effect. They think premium is better, therefore their engine feels like it runs better. The only real time you need to up the octane is if you get ping or knock.
Obviously, if the motor is not stock, and I don't mean ecu mods, then you may need premium. Higher compression, more advanced timing, engine load, these are factors for determining is premium is needed.
Also, in older bikes, the ignition systems were not very strong, primarily points ignitions. Premium doesn't always fully burn in these engines. Fuel that doesn't burn fully increases carbon buildup on the pistons and cylinders. It is possible for carbon to flake off and actually score the walls.
It is your bike though. You can use premium if you want, but you will almost certainly not gain anything by doing so.