NA4911-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 NA4911-XL model number is decoded

envelope 55×80×25 mm: 55 mm bore accepts a normal-tolerance machined shaft via the integral inner ring, with a thin 12.5 mm radial section packed with small-diameter needle rollers C is 65 kN and C0 100 kN at the 55 mm seat; the C/C0 ratio of 0.65 is characteristic of a needle bearing — high static rating relative to dynamic in a compact 80 mm outside diameter the fatigue load limit Cur is 17.6 kN, the limiting speed 7,200 r/min and the thermal reference speed 4,000 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 1.18 kN/mm and per millimetre of width 2.60 kN/mm — the reason 25 mm-wide needle bearings routinely replace much larger ball or roller positions mass is 393 g, just 0.20 g per mm² of projected 80×25 mm envelope, which keeps unbalanced forces low in fast-actuating linkages 55 mm bore marks the medium range: mounting forces and fits become critical, and the 393 g mass calls for proper induction or press tooling rather than hand fitting The integral inner ring brings the bore to 55 mm inside the 80×25 mm envelope; removing that ring gives the corresponding RNA/NK execution and a larger shaft for the same housing The inner ring is separable, so the outer-ring/roller assembly can be pressed into the housing first; the 100 kN C0 rating still assumes full rigid support under both rings The -XL suffix is the Schaeffler X-life mark: interchangeable envelope with the basic bearing, but higher load capacity and lower running temperature at the 7,200 r/min limit. Typical applications include connecting-rod small ends, textile machine heald and cam shafts and motorcycle and light-vehicle transmissions, where the 80 mm outside diameter and 65 kN dynamic rating match the duty. In connecting-rod small ends the unit fits a compact 55 mm seat, and in textile machine heald and cam shafts the 393 g mass keeps unbalanced forces low in fast linkages. Designers also specify it for motorcycle and light-vehicle transmissions, relying on the 25 mm width and the published 100 kN static rating. Adding an IR inner ring changes the envelope logic: the same outer assembly then fits a smaller shaft — recheck bore, clearance and ratings when substituting. Needle bearings are pure-radial units — any thrust must be taken by separate washers or an adjacent bearing, especially on flangeless RNAO/NAO.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Adding an IR inner ring changes the envelope logic: the same outer assembly then fits a smaller shaft — recheck bore, clearance and ratings when substituting.
• Needle bearings are pure-radial units — any thrust must be taken by separate washers or an adjacent bearing, especially on flangeless RNAO/NAO.
• On reciprocating duty ensure the stroke rotates the full needle set, or brinelling occurs at the same roller positions.