In engines having more than two rotors, or two rotor race engines intended for high-rpm use, a multi-piece eccentric shaft may be used, allowing additional bearings between rotors. While this approach does increase the complexity of the eccentric shaft design, it has been used successfully in the Mazda's production three-rotor 20B-REW engine, as well as many low volume production race engines. The C-111-2 4 Rotor Mercedes-Benz eccentric shaft for the KE Serie 70, Type DB M950 KE409 is made in one piece. Mercedes-Benz used split bearings.