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The effects of two types of intake ports on the in-cylinder bulk flow and turbulence structure were investigated in steady flow tests by using laser doppler anemometry. The results, obtained at constant mass flow-rate in a plane 15 mm or 0.19 bore diameters from the cylinder head, confirmed the expected differences in the tangential flow pattern, but revealed similarity in the axial velocity distribution characterized by a large recirculation zone (RZ) attached to the inlet valve. In both cases the turbulence was found higher, more inhomogeneous and more non-isotropic in the regions of positive axial flow than in the RZ. Localized highly turbulent conditions have been identified and characterized as a consequence of bi-modal probability distribution functions (pdf) of velocity and aperiodic oscillations from one velocity regime to another.