I would recomend not using 93 octane more than once a month. The detergents used in premium will break down the 2 stroke oil. In a four stroke this is a good thing but in a moped it can be lethal to the engine. You should try to use 87 octane as much as possible. 89 isn't too bad. Some states like Maryland allow mixed-midgrade, which is 87 and 93 mixed to get 89. This can be as bad as 93. Cam-2 can be mixed in a moped but I wouldn't do it too much and never more than 3oz. to a gallon.