Parts Gas
What does "parts" mean when you are mixing oil and gas for a two stroke engine?

I am going to purchase a 80cc bike engine and it says since this is a two sroke engine you have to do a gas to oil mix ratio and it says 20-25 to 1 part synthetic two stroke. And I am wondering what a part is read that a part means just one cup but I just want to make sure.

Well what it basically means is that for every 20-25 ounces of gas you mix in 1 ounce of oil, so if you use 50 ounces (two parts) of gas you use 2 ounces (two parts of oil. At a ratio of 25:1, which is what you've got a gallon of gas requires 5.12 ounces of oil.