Processes for catalytic reforming in which a cracking inhibitor, such as an olefin, or a light olefin, is used to inhibit thermal cracking of larger hydrocarbons in non-reactive zones. The cracking inhibitor may be added at various positions through the processes, such as in the recycle gas stream, before a heater, before a stream is passed into a reforming zone, after an effluent stream is recovered from a reforming zone. A molar ratio of cracking inhibitor to hydrocarbons in stream may be between 0.01 and 0.2.