The directions on the container of Ring Free suggest a "constant" treatment 1oz per 10 gallons of gasoline. Am I to understand I should be adding 2oz per 10 gallons for my twin engines? The directions on the bottle seem ambiguous. Any thoughts?
You want the fuel to deliver the proper mix. You mix 1:10 and both motors will get the prescribed ratio. (presuming they both run off the same tank(s).