Was reading an article in the June '13 Cycle World magazine: "Octane boosters suppress or retard ignition and are usually a waste of time. But what most people don't know is that a container of octane booster that claims to increase octane 10 points only increases it by one number. Not only that, bikes with catalytic converters have to use octane boosters very sparingly because the MANGANESE used in almost all of those products will destroy the catalyst metals. Manganese is also very harmful to your body, so care needs to be taken not to get any octane booster on your hands". I've never used any in the VFR but have in my hotrod, no cats on it.