I've used it in cars a couple times. In one it seemed to help, in the other I couldn't notice a difference (but there turned out to be another issue at hand). A lot of people swear by it, others swear it does nothing.
In bikes you use 1oz per gal of gas to the tank. Ive used it in tank and I guess it works. My carb and plugs are nice and clean.
04 Aero 750 Cobra HP Pro Exhaust,Wrapped De-snorkeled,K&N AF, Dyno Jet JK Blue Collar Bobbers 31" Drag bars and Risers, Avon Grips,Baron Tach Goodrich Braided SS/Black Teflon front brake line, EBC HH Front brakes/EBC Rear shoes ScootMods 4" Control Extensions ScootWorks Front/Rear 1.5 Lowering Kit Shaved Stock Seat (Self made) Flush Mount Tag (Self made)