1931 350cc
Frame
Numbered 42996 to 46500 (approx). Bolt on seat stays with drawback type chainstays for rear wheel adjustment.
Wheels
WM1x21 (f), WM1x21 (r). interchangeable with black painted rims. Black spokes with NPB nipples. Bolt on rear sprocket.
Mudguards
Inverted 5 1/2” wide U section, both unvalanced. Rear, with hinged tail section.
Tanks
Petrol tank finished in black & gold. Single offset CEE-ESS type filler with front fitted petrol balance pipe. Single bolt damper arm fixing. Brass lever petrol tap. Oval 'Rudge-Whitworth' rubber gnee grips.
Engine
Numbered 1 to 4900 (approx) - 4 valve 349cc with cast iron open valve fully radial cylinder head.18mm central plug. Rear mounted round CMAK ML magneto and forward mounted DM3G Miller dynamo. Plain cast alloy rocker box. Oil feed to rear of cylinder.
Brakes
6 3/4” front and rear, coupled with steel shoes.
Electrics (optional)
Miller 7” headlamp (bayonet fitting rim) with No 74E or later No 75 6-0-6 'Lighthouse' ammeter (illuminated) and 34E (early models), 39E or 39ER (latest models) rear lamp. Later machines used the No 74ES headlamp with the clip fitting rim. DM3G dynamo.
Transmission
4 speed gearbox with hand change on RHS of tank. Steel open backed primary chain cover with an identical aluminium version being introduced for later production machines. Steel rear chain guard.
Carburetter
Amal type 6/109 with Amal straight pull twist grip control
Exhaust system
Twin 1 1/2” low-level downpipes into Rudge ‘can’ type silencers and 6” fishtails.
Standard Fittings
Rear carrier (extra at no charge), 1” handlebars with folded type inverted levers and steering damper. Single toolbox fitted to offside of machine. Spanner adjusted fork shock absorber. Pressed steel centre stand. Open ended ‘D’ section forks.
Extras
Chrome plated petrol tank with black or maroon panels and black with maroon guards & tank panels. Smith’s trip/non trip speedometer, Smith’s 2" (2.4" diameter) 8 day clock in damper arm, Bonniksen speedometer, legshields, electric horn and Lucas No 63 bulb horn. Optional 2 lever control to carburetter. WM2x19” or WM2x21” wheels.