Frame

Numbered 30940 to 36442 (approx) in Rudge sequence. Semi strutted with struts from the rear wheel to the front of the crankcase and from the crankcase to the steering head (special frame lug). Special kneehook lug. Special frame lug (unused) under saddle. Steering head fork stop machined off. Bolt on seat stays with drawback type chainstays for rear wheel chain adjustment

Wheels

WM1x21 (f), WM1x21 (r) wired on type, interchangeable small flange (dog drive hubs) with nickel plated rims, spokes & hubs.

Mudguards

Short back (5”D section) and front ‘D’ section, nickel plated.

Tanks

Bright red enamelled of soldered construction. Fuel tank fitted inside frame tubes tapers front to rear to fit within frame struts. Oil tank fixed to rear frame downtube. Screw fillers to both tanks.

Engine

Based on the 1929 Ulster - 4 valve 499cc with iron open valve parallel inlet & parallel exhaust cylinder head with integral cast exhaust ports. 18mm CENTRAL plug but with retained side plug fitting (blanked off). Early examples used the standard Ulster head with 1 3/4" OD exhaust stubs but later changed to 1.5" ID heads with unmachined stub OD.  Rockers supported in large nuts in rocker plates bolted to the cylinder head. Forward mounted ML magneto. Square based cylinder barrel and webbed (6) drive side crankcase. Total loss oiling with vertical adjustable ‘pump’ in timing cover. Oil feed to rear of cylinder.

Forks

Rudge 1927/8 pattern closed ended with brake anchor attachments removed. Nickel plated.

Transmission

Gearbox countershaft with clutch and dog drive rear hub. 1/2”x 0.305 chains.

Carburetter

Sports type Amac 10MDY with quick action twist grip.

Exhaust system

Two 1 3/4" (later 1.5") nickel plated open pipes, finishing on the off side of the machine. Offside pipe finishing around the gearbox area and nearside (same length) finishing short of this.  Pipes originally fitted over cast in cylinder head stubs and later (1.5") inside the stubs and secured by a bolt.

Standard Fittings

1” non adjustable nickel plated handlebars with André type steering damper. Riveted angle & strip steel centre stand and magneto cut out on handlebars.

©  Colin Chapple