We hypothesize that some overlap of production between and within product generations reduces firm mortality, as it allows firms to retain valuable routines. Excessive overlap, however, becomes harmful. An analysis of the effects of new product introduction on mortality rates among the population of US bicycle producers over 1880-1918 supports our hypotheses. Our results suggest the value of separating out the content effects of innovation, which are often positive, from the process effects which tend to be disruptive.