Malossi MHR Replica 79cc Cylinder Kit - Derbi D50B0 50cc. This product is suitable for the Aprilia RS50 06-10 (D50B0) ZD4PL / ZD4RG. The MHR Replica cylinder kit was originally developed for the international 70cc Scooter Trophy to achieve a solid engine performance combined with a strong torque already at lower revs.
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