Reading Part Numbers

Four Inch Wheels (W4 Series)

Example: NW40B

NW40B
Letters here indicate type of wheel (T = tail wheel; N = Nose wheel; no letter = main)

NW40B
W4 indicates 4″ cast wheel

NW40B
Valve hole size (0 = 7/16 1 = 5/8)

NW40B
Bearing type (R = roller B = ball)

NW40B___
Bearing size (ie:NW40B.0625) if no number assume 3/4 inch.

Five Inch Wheels (W5 Series)

Example: W50S1.25

___W50S1.25
Letters here indicate type of wheel (N = Nose wheel no letter = main)

W50S1.25
W5 indicates 5″ cast wheel

W50S1.25
Valve hole size (0 = 7/161 1 = 5/82 )

W50S1.25
Boss length (S = Short L = Long)3

W50S1.25
Bearing size (if no number assume 1 1/4*)

Six Inch Wheels (W6 Series)

Example: W60

W60
W6 indicates 6″ cast wheel

W60
Bearing size (00 -> 1.5″, 0 -> 1.25″, 1 -> 1″, 2 -> .75″)

Ultralight Wheels (MH Series)

MH5B.75

MH5B.75
MH series are ultralight wheel for airplanes 1300 pounds or less

MH5B.75
Wheel size (5 = 5″ 6 = 6″)

MH5B.75
Wheel type (B = main N = nose)

MH5B.75
Bearing size (if no number assume 5/8)

Notes

* For nose wheel if no number assume 3/4

1 Indicates a Lamb type tire should be used

2 Indicates an aircraft tire should be used

3 Letters following the S or L indicate type of brake D = dual caliper T = triple piston