Enginetech BC3201.25 0.25mm Undersize Main Bearing Set for 2012-2021 Mazda 2.0L 122ci I4 - Complete OEM-Spec Main Bearing Set

Enginetech BC3201.25 is a 0.25mm undersize main bearing set for 2012-2021 Mazda 2.0L 122ci I4 engines.

Important Notes:

• Sized for crankshaft main journals machined .25mm undersize. Measure journal diameter before installation - installing on the wrong journal size will cause immediate clearance failure.
• Always replace main bearings as a complete set. Never mix new bearings with used bearings - uneven wear and clearance differences will cause premature failure.
• Thrust washer not included. Use TW3201.

Complete main bearing set covering all main journals for the I4 application - one set required per engine.

Fitment:

• 2012-2013 Mazda 3 2.0L 122ci I4
• 2012-2013 Mazda 3 Sport 2.0L 122ci I4
• 2012-2021 Mazda 3 2.0L 122ci I4
• 2013-2016 Mazda CX-5 2.0L 122ci I4
• 2014-2020 Mazda 3 Sport 2.0L 122ci I4
• 2016-2020 Mazda CX-3 2.0L 122ci I4
• 2016-2020 Mazda MX-5 2.0L 122ci I4
• 2016-2021 Mazda MX-5 Miata 2.0L 122ci I4
• 2020-2020 Mazda CX-30 2.0L 122ci I4

Enginetech main bearings are engineered to OEM specifications, drawing on over 40 years of engine rebuilding expertise to deliver the precise clearance, crush, and eccentricity required for long-term durability under both stock and moderate-performance loads. Each set is application-specific: materials, wall thickness, oil clearance, and surface finish are all matched to the crankshaft main journal geometry and operating loads of the engine family it serves. Main bearings are a wear component and must be selected to match the crankshaft main journal size - bearings sized for standard journals will not seat correctly on undersize-machined journals and vice versa, so verify your journal measurement with a precision micrometer before ordering or installing. Always replace main bearings as a complete set. Mixing new bearings with used bearings produces uneven oil clearance across the crankshaft and accelerates wear on the freshly installed bearings - the small cost of a complete set is insurance against premature failure on the bearings you just paid to install. Enginetech documents every set with clear application-specific notes, journal-size designation, and cross-references so the right part lands on the bench the first time.

WARNING: This product can expose you to chemicals including likely lead/nickel — verify, which is known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, go to www.P65Warnings.ca.gov.