RNA4872-XL bearing: complete specifications & equivalents

Specification table

Source: catalog reference (HR1 2026-09-25) · extracted 2026-09-30

Parameters extracted from the official FAG Rolling Bearings catalogue (HR1 2026-09-25); FAG® is a trademark of Schaeffler Technologies AG & Co. KG, used here for identification only — mpnbase is not an authorized FAG/Schaeffler distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at schaeffler.com.

Cross references & equivalents

Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.

How the RNA4872-XL model number is decoded

envelope 390×440×80 mm: 390 mm seat is the hardened and ground shaft journal itself — there is no inner ring, with a thin 25.0 mm radial section packed with small-diameter needle rollers C is 740 kN and C0 2020 kN at the 390 mm seat; the C/C0 ratio of 0.37 is characteristic of a needle bearing — high static rating relative to dynamic in a compact 440 mm outside diameter the fatigue load limit Cur is 260 kN, the limiting speed 1,210 r/min and the thermal reference speed 600 r/min; for small needle bearings the reference speed can exceed the kinematic limit, so the lower of the two governs the application dynamic capacity per millimetre of bore is 1.90 kN/mm and per millimetre of width 9.25 kN/mm — the reason 80 mm-wide needle bearings routinely replace much larger ball or roller positions mass is 14.8 kg (14800 g), just 0.42 g per mm² of projected 440×80 mm envelope, which keeps unbalanced forces low in fast-actuating linkages the 390 mm bore puts this execution at the top of the HR1 range — the 440 mm outside diameter, 80 mm width and 14.8 kg mass are built for primary-industry load cases Reading the RNA48 prefix: a machined (not drawn-cup) outer ring with the needle complement; an inner ring from the IR series can be added later if the shaft cannot be hardened The hardness requirement is unforgiving: below about 58 HRC the 390 mm journal brinels under the 2020 kN static rating, and roughness above raceway finish accelerates roller wear The -XL suffix marks the X-life execution: refined raceway topography and upgraded materials lift the basic ratings versus the non-X-life bearing at the same 390×440×80 mm envelope. Typical applications include two-stroke and compressor piston pins, motorcycle and light-vehicle transmissions and rocker arms and valve trains, where the 440 mm outside diameter and 740 kN dynamic rating match the duty. In two-stroke and compressor piston pins the unit fits a compact 390 mm seat, and in motorcycle and light-vehicle transmissions the 14.8 kg mass is part of the rotor inertia calculation. Designers also specify it for rocker arms and valve trains, relying on the 80 mm width and the published 2020 kN static rating. Open ends draw contamination directly onto the needles; specify sealed or shielded positions in dusty environments rather than relying on grease alone. Keep the specified radial clearance; an oversized shaft or heavy interference removes it and the needles bind hot immediately.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Open ends draw contamination directly onto the needles; specify sealed or shielded positions in dusty environments rather than relying on grease alone.
• Keep the specified radial clearance; an oversized shaft or heavy interference removes it and the needles bind hot immediately.
• On reciprocating duty ensure the stroke rotates the full needle set, or brinelling occurs at the same roller positions.