I have used both Seafoam and B-12 and they both seem to work about the same. The Seafoam is more expensive. I let a 4 carb Kawasaki sport bike sit too long and it wouldnt idle on its own and was running very rough. Added a full can ofB-12 to a tank of gas and drove it 40 miles. By the time I got home it was smooth and running fine. Now I use it about every 6 months as a preventative cleaner. I also use green stabil at the end of every ride because I never now how long it will be sitting since I have 3 bikes.