NA4907-XL bearing: complete specifications & equivalents

The NA4907-XL is a ISO 15 radial bearing sized 35 x 55 x 20 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.

Bearing dimension schematic Front view shows outer diameter D and bore d; side section shows width B. D = 55 mm d = 35 B = 20 mm side section front view
Principal dimensions: bore d 35 mm, outer diameter D 55 mm, width B 20 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand FAG
Bore diameter d 35 mm
Outer diameter D 55 mm
Width B 20 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage steel
Basic dynamic load rating C 35.5 kN
Basic static load rating C0 50 kN
Fatigue load limit Pu 9.6 kN
Reference speed (thermal) 5800 rpm
Limiting speed (mechanical) 10700 rpm
Operating temperature -40 to +120 °C
Mass 170 g
Manufacturer designation NA4907-XL
Standard ISO 15
Catalog version HR1 2026-09-25
Last verified 2026-09-30

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.

Dimensions in inches & na49-series range

Bore d 1.378 in
Outer diameter D 2.165 in
Width B 0.787 in
ISO bore code 07
Radial section height (D−d)/2 10 mm
Smallest bore in na49-series 10 mm
Largest outer diameter in na49-series 190 mm
Width range across na49-series 13–50 mm
Bore position in na49-series (smallest first) 11 of 28
Bore above smallest na49-series size 25 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
NA4907 SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 35×55×20 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting.
NA4907-2RS SKF verify
Commonly quoted cross reference; confirm against the target catalog before ordering.
Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue.

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 NA4907-XL model number is decoded

envelope 35×55×20 mm: 35 mm bore accepts a normal-tolerance machined shaft via the integral inner ring, with a thin 10.0 mm radial section packed with small-diameter needle rollers C is 35.5 kN and C0 50 kN at the 35 mm seat; the C/C0 ratio of 0.71 is characteristic of a needle bearing — high static rating relative to dynamic in a compact 55 mm outside diameter the fatigue load limit Cur is 9.6 kN, the limiting speed 10,700 r/min and the thermal reference speed 5,800 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 1.01 kN/mm and per millimetre of width 1.77 kN/mm — the reason 20 mm-wide needle bearings routinely replace much larger ball or roller positions mass is 170 g, just 0.15 g per mm² of projected 55×20 mm envelope, which keeps unbalanced forces low in fast-actuating linkages at 35 mm bore this is a mainstream industrial size — conveyor drives, winches and medium gearboxes use the 20 mm width as a standard mounting space This is the choice for OEM production on soft shafts: machine the 35 mm seat to the recommended tolerance, fit the bearing, and let the inner ring provide the precision raceway Cur 9.6 kN, limiting speed 10,700 r/min, reference speed 5,800 r/min — the inner ring adds a few grams (total 170 g) but removes the hardening requirement X-life status (-XL) indicates the current Schaeffler premium execution at 35 mm bore; the 50 kN C0 rating reflects the improved rolling-contact geometry. Typical applications include agricultural machine pivots and linkages, hydraulic and pneumatic pump eccentrics and textile machine heald and cam shafts, where the 55 mm outside diameter and 35.5 kN dynamic rating match the duty. In agricultural machine pivots and linkages the unit fits a compact 35 mm seat, and in hydraulic and pneumatic pump eccentrics the 170 g mass keeps unbalanced forces low in fast linkages. Designers also specify it for textile machine heald and cam shafts, relying on the 20 mm width and the published 50 kN static rating. On reciprocating duty ensure the stroke rotates the full needle set, or brinelling occurs at the same roller positions. Open ends draw contamination directly onto the needles; specify sealed or shielded positions in dusty environments rather than relying on grease alone.

Typical equipment & failure modes

Common applications

  • motorcycle and light-vehicle transmissions
  • hydraulic and pneumatic pump eccentrics
  • two-stroke and compressor piston pins
  • rocker arms and valve trains

Known failure patterns

  • journal brinelling when a no-inner-ring bearing runs on a shaft hardened below 58 HRC or finished too rough
  • needle skewing and jamming after momentary unloading of a flangeless (RNAO/NAO) pack
  • raceway pitting from contamination drawn through the open ends of an unsealed bearing
  • edge loading at the roller ends from a tapered or lobed shaft seat
  • cage damage from shock loading or from pressing the bearing through the wrong ring
  • lubricant starvation on fast reciprocating strokes that never fully rotate the needles
  • false brinelling during stationary transport vibration
  • spalling from excessive interference that removes the radial clearance
  • roller wear from misaligned connecting-rod eyes and rocker bores

Selection pitfalls — read before you substitute

  • On reciprocating duty ensure the stroke rotates the full needle set, or brinelling occurs at the same roller positions.
  • Open ends draw contamination directly onto the needles; specify sealed or shielded positions in dusty environments rather than relying on grease alone.
  • Do not press an RNA/NK assembly in through the outer ring when mounting it on a shaft, and vice versa — rolling forces through the wrong ring bruises the raceways.

Frequently asked questions

What are the dimensions of the NA4907-XL?

The NA4907-XL is a NA49 dimension-series 49 needle roller bearing with inner ring with 55 mm outside diameter, 35 mm bore and 20 mm width, envelope 35×55×20 mm. Mass is 170 g.

What does the NA4907-XL designation mean in the FAG/INA HR1 catalogue?

NA4907-XL identifies this NA49 dimension-series 49 needle roller bearing with inner ring in the Schaeffler HR1 rolling bearings catalogue; the -XL suffix marks the X-life execution. The envelope is 35×55×20 mm and the catalogue ratings are C 35.5 kN, C0 50 kN, Cur 9.6 kN.

What is the load capacity of the NA4907-XL?

The basic dynamic load rating C is 35.5 kN and the basic static load rating C0 is 50 kN; the fatigue load limit Cur is 9.6 kN.

What is the maximum speed of the NA4907-XL?

The limiting speed is 10,700 r/min and the thermal reference speed is 5,800 r/min. In the Schaeffler catalogue the reference speed is the thermally permissible running speed under defined load; the lower of the two values governs each application.

How is the NA4907-XL mounted on the shaft?

The integral inner ring accepts an ordinary ground shaft at the 35 mm nominal bore with the recommended normal bearing-seat tolerance; no hardening is required. The ring is separable, so the outer assembly can be pressed into the housing first and the inner ring fitted with the shaft.

Reviewed & verified by the MPN Base engineering desk against source catalog HR1 2026-09-25 on 2026-09-30. Read our editorial & correction policy.