Replacement bearing set (left-right) for the original SKF-NJ cylindrical roller bearings of the KTM SMR / SX-F 450-505. Manufacturer NTN - Precision bearings from the Japanese market leader NTN. Redesigned for installation in the SMR engine. Higher service life and smoothness. Unfortunately, this engine concept can not be converted to TMB deep groove ball bearings, since components are screwed against the shaft on both left and right crankshaft construction.