The combination of an instrumented molding device,simulating the vulcanization bonding process of rubber to metal assemblies, and a model natural rubber compound with a predictable cure kinetics allowed us to demonstrate a correlation between the presence of the reversion phenomenon at high cure temperature and decrease of adhesion performance. The molding device described allows the production of adhesion peeling test samples under well controlled curing temperature cycles, which can be characterized using a standard peeling test. It was observed that both the peeling resistance and the peeling energy decrease when the cure temperature is increased. For that latter, the decrease is inversely proportional to the reversion undergone by the rubber during cure. Such a result points out the necessity of taking the reversion phenomenon for the optimization of the vulcanization bonding process into account.