NKS65-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 NKS65-XL model number is decoded

envelope 65×85×28 mm: 65 mm seat is the hardened and ground shaft journal itself — there is no inner ring, with a thin 10.0 mm radial section packed with small-diameter needle rollers C is 75 kN and C0 108 kN at the 65 mm seat; the C/C0 ratio of 0.69 is characteristic of a needle bearing — high static rating relative to dynamic in a compact 85 mm outside diameter the fatigue load limit Cur is 19.4 kN, the limiting speed 6,900 r/min and the thermal reference speed 4,400 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 1.15 kN/mm and per millimetre of width 2.68 kN/mm — the reason 28 mm-wide needle bearings routinely replace much larger ball or roller positions mass is 356 g, just 0.15 g per mm² of projected 85×28 mm envelope, which keeps unbalanced forces low in fast-actuating linkages at 65 mm bore the 85 mm outside diameter and 28 mm width target rolling stands, construction machinery and heavy gearboxes; the limiting speed drops to 6,900 r/min Reading the NKS 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 65 mm journal brinels under the 108 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 65×85×28 mm envelope. Typical applications include small electric motor accessory drives, rocker arms and valve trains and planetary gear bearings, where the 85 mm outside diameter and 75 kN dynamic rating match the duty. In small electric motor accessory drives the unit fits a compact 65 mm seat, and in rocker arms and valve trains the 356 g mass keeps unbalanced forces low in fast linkages. Designers also specify it for planetary gear bearings, relying on the 28 mm width and the published 108 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.