torok: What does it say on the Owners Manual. I use regular non-leaded petrol of 97 octaine on my '97 Yamaha YZF600r & '00 Honda 929 with no pre-ignition.
Have tried up to 91 (only do a few rare stations ever have 92 or 93 so even tried that) & cannot see any difference in power to the bike, heating, fuel milage, etc. My Owners Manual, of both bikes, says 86 octane or up.
Basically since '46 all I have ever used was pump fuel, bar times I was experimenting. Just one thing I do is buy from stations I know to have fresh or good underground tanks. To often the older & especially the slightely lower priced to discount stations have tanks that are leaking out gas & taking in undergound liquids not to mention how some will illegally pump in diesel fuel to regular or high octane tanks. I have no idea how they do this, but some have been cought when the fuel was tested. Have some of that crap in your engine & it will suffer.
One can always spot a good station by the appearance of the station building being only a few yrs old, the newer pumps & that the surface has been done over again.