Frame

Numbered 46501 to 49600 (approx). Bolt on seat stays with drawback type chainstays for rear wheel adjustment.

Wheels

WM1x21 (f), WM2x20 (r) with chrome rims. Black spokes with NPB nipples. Bolt on rear sprocket.

Mudguards

Racing type. Rear with extra strip steel stay.

Tanks

Petrol tank, black with gold lining. Twin Coventry movement fillers with front fitted petrol balance pipe. Single bolt damper arm fixing and 8 bolt tank fixing. Twin brass lever petrol taps. Oil tank mounted on rear frame tube with 2 Coventry Movement fillers, one either side of machine.

Engine

4 valve 349cc/499cc with cast iron TT type open valve fully radial cylinder head.18mm central plug and oval inlet port. 500cc with 7/16" head bolt holes and 2.2" carb mounting centres. Forward mounted round ML racing magneto. RR50 crankcases, drive side crankcase with 8 webs and timing side crankcase with a single web. Round base to cylinder barrel with rear oil feed.

Brakes

8” front and rear, coupled with steel shoes. RHS foot operated.

Transmission

4 speed close ratio  TT replica type gearbox with foot change on LHS using rocking pedal.

Carburetter

Amal 10TT32  1 5/32” (500cc) and 1 3/32” (350cc)

Exhaust system

Twin 1 1/2” low-level downpipes into Rudge ‘can’ type silencers and 6” fishtails.

Standard Fittings

1” TT pattern handlebars with Bowden single cable handlebar controlled damper and folded type clutch and inverted levers. Single high level leather fronted toolbox fitted to offside of machine. Pressed steel central stand. Open ended ‘D’ section front forks with brazed fork bridge and spanner adjusted shock absorber.

©  Colin Chapple