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To better understand the complex scavenging process in ported two-stroke engines, velocity measurements were taken at the exit of an intake port of a motoring and firing single-cylinder propane-fueled two-stroke engine by Laser Doppler Velocimetry (LDV). The radial velocity component was measured at the center of one port at engine speeds of 600, 900, and 1200 rpm. Cylinder pressure was also recorded for both motoring and firing cycles. When plotted versus crankangle, it was observed that the intake flow ensemble-averaged mean velocities have a characteristic two-end-peak profile with peaks occurring just after the piston exposes or is about to block the measurement volume. The two peaks occurred at approximately the same crankangle in both the motoring and firing engines. At 600 rpm the two velocity end peaks in the fired engine are larger than the corresponding motored values by a factor of 1.73 to 2.26.