What's the proper way of using the product? With full or half tank of gas? Is it recommended to do motor oil change after the cleaner? Thank you in advance for help.
To utilize BG44K, put the entire can in your fuel tank just prior to fill-up at the gas pump. This will ensure the product is completely mixed with your fuel. You should use at a ratio of one can to an entire fuel tank (for passenger car/truck). If using it in a motorcycle or some other small engines, you will need to decrease the amount used, but figure about one can per 15-18 US gallons.
BG44K is a fuel treatment. It should be used in the gas tank. BG has other products which can be used to treat the oil. There is no need to change the oil or filter when using BG44K by itself. If you get other treatments, it may be required.
I understand the BG44K can has very little instruction on it. The BG website has even less. I am going to assume it is this way because BG44K can only be purchased through a licensed dealer, which is usually a maintenance garage. You will not (as of this post) find it at WalMart, Target, or other such stores. I have seen it for purchase on eBay, though.
The product page describes the product as follows:
As it is spring, I'm assuming this stuff is supposed to end up in a bike. I have never used it, or even know if it's available in my country, but why not scale it down to the corresponding ratio for your tank volume? I cant find any instruction, but should they not be printed on the bottle it's that important?