I'm finding that number in my Lucas Girling 1960-1968 catalog under Norton 750cc N15CS and P11 1965-1968. I don't have a scanner but the only info there under Girling is:
Suspension unit: 64054590
Ferrule tube and bush ass'y: 64533645
Spring: 9054/94
Outer Dirt Shield: 64532981A
Did you check Christian's Archives? Edit - It's in there under Technical - Electrical (
http://archives.jampot.dk/)
Russ
These are on Feked as Hagon replacements for Matchless G15CS models from 1965 onwards
3 position spring pre-load, adjustment by enclosed stepped cam ring.
110lb (20kg) medium weight progressive springs are fitted as standard.
Supplied with spring adjuster spanner.
2 year guarantee.
Length: 13.4", 13+3/8" (340mm) between eyelet centres
Top bush ID: 3/8" (10mm)
Top bush width: 15/16" (24.5mm) for 1" mounting points
Bottom bush ID: 3/8" (10mm)
Bottom bush width: 15/16" (24.5mm) for 1" mounting points
OEM: Girling 64054590 (reference only), 34003CL3
However, of Feked the P11 lists as
12.9" Hagon Shocks - Norton P11/P11A + AJS Model 16, 18, 31, 33 From 1963 Onwards - Open Spring
3 position spring pre-load, adjustment by enclosed stepped cam ring.
Supplied with spring adjuster spanner.
110lb (20kg) heavyweight progressive springs are fitted as standard.
2 year guarantee.
Length: 12.9", 12+7/8" (330mm)
Top bush ID: 3/8" (10mm)
Top bush width : 15/16" (24.5mm) for 1" mounting points
Bottom bush ID: 3/8" (10mm)
Bottom bush width : 15/16" (24.5mm) for 1" mounting points
OEM: Girling 64054493, 33007SS