Mazda Factory Race (MFR) Rotor Bearing (Sold Individually)

The Mazda Factory Race (MFR) rotor bearings for all 12A & 13B engines are the best bearings available of engine operation near or above 8500 RPM. The rotor bearings are manufactured with a deep groove for additional oil storage and offer an additional .0005″ (approximate) clearance. These bearings can be used in 1973 and earlier engines by grinding off the indexing tab.

Competition bearings have 0.01 inch deeper oil groove and provide 0.0005 inch more clearance than stock bearings. Thinner overlay material improves bearing service life.

These bearings are special order only and can take up to 6 weeks for delivery. They are sometimes out of stock at Mazda HQ Japan so can take longer. we would recommend ordering your competition bearings early to avoid disappointment.

THESE BEARINGS ARE SOLD INDIVIDUALLY