8′ 1″ diam., 24 rectangular spokes, rectangular inner rim, apparent tread 3½″, tyre width 5¼″.
Hub 20″ face dia., 2″ out from the tyre, pin between at 14″.

Sources: measurements direct from preserved loco No. 1 at NRM, York, June 1995.
The Stirling Singles, Leech and Body, David and Charles (1965), page 53. (Tyre width).
Great Northern Locomotive History, RCTS, vol. 2, p. 210. Stating that the preserved Loco is fitted with a pair of old wrought-iron driving wheels, but not of the original design. (Without saying how they differed.)

Casting: 80.8 mm tread o/d., 74.6 i/d., hub 1.7 mm out from the tyre, pin at 11.7 mm.

Casting prices and stock . GN loco sets, price list

Scan of a casting in a set for a GN 4-2-2 with prototype photographs.