Numbered 53961 to 55700 (approx). Integral seat stays with cam type chainstays for rear wheel adjustment.
WM1x21 (f), WM2x20 (r). Chrome rims. Black spokes with NPB nipples. Bolt on rear sprocket.
Plain inverted U section, unvalanced. Rear with detachable main section.
‘Aero ’petrol tank painted with double lined panels. Single central CEE-ESS type filler with front fitted petrol balance pipe. Two bolt damper arm fixing. Enots non reserve petrol tap. No cut out for access to spark plug.
Numbered U601 to U1000 - 4 valve 499cc with aluminium bronze cylinder head, parallel inlet valves and radial exhaust. 14mm central plug. BTH KC1 D4 magneto (later production used the KD1 D4) and DM3G Miller dynamo. Oil feed to rear of cylinder. Cast alloy rocker cover with ‘R’ motif.
8” front and rear, coupled with aluminium shoes.
Miller 8” headlamp with No 832 8-0-8 'Lighthouse' ammeter and 29E rear lamp. Lucas ‘Altette’ electric horn. Stop lamp.
4 speed gearbox with foot change on LHS. Aluminium oil bath chaincase with ‘R’ on dome and separate filler on shock absorber dome. Heavyweight clutch.
Amal type 29/146 with Amal straight pull control. Original settings: Main jet 170, slide 29/5, needle jet 109, needle position 3. Smiths Petroflex fuel line.
Twin 1 3/4” high level pipes with heat shields into barrel silencers and plain tailpipes.
120MPH trip speedometer and Smiths 3" C55 8 day clock. Mechanism shield, battery cover, licence holder, pressed steel central stand with lifting handle. 1” handlebars. High level toolbox fitted to offside of machine. Steering damper and handwheel operated fork shock absorber. Lycett 6B pillion pad with 2 securing screws at the front and 2 at the rear. Open ended ‘D’ section forks. NO lower chainguard valence.
Pillion footrests, Rudge quickly detachable and interchangeable wheel on Watsonian or Swallow sidecar.