octane requirements are not just reliant on compression or dome size alone ,the exhaust port height , the ignition timing ,and squishband clearance all come into play . 100ll aviation fuel would be my recomendation for you,id say bout anything over 105 will work ,youl lknow if its detonating ,plugs will have tiny aluminum specks on them and youll hear the bike popping/pinging and hesitating