Simonini Racing S.r.l. is an Italian automotive and aircraft engine manufacturer based in San Dalmazio di Serramazzoni. The company specializes in the design and manufacture of small engines and racing conversion kits for motorcycles and microlight aircraft.Simonini Racing is organized as a Società a responsabilità limitata, an Italian limited liability company.The company produces a line of small engines, racing conversion kits, mufflers and parts.