Frame

Numbered 42996 to 46500 (approx). Bolt on seat stays with drawback type chainstays for rear wheel adjustment.

Wheels

WM1x21 (f), WM2x20 (r). with black enamelled rims. Black spokes with NPB nipples.

Mudguards

Racing type.

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 499cc with cast iron TT type open parallel valve cylinder head.18mm central plug and oval inlet port. Tubular rockers mounted on plates bolted to the cylinder head. Forward mounted round ML racing magneto running at half engine speed. 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 and 4 not 3 lower fin set using a 7.5" conrod.

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. Sheet steel chainguard to top run of primary chain. ‘Angle iron’ rear chainguard.

Carburetter

1 5/32” 10TT 27 with twin float chambers.

Exhaust system

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

Standard Fittings

1” TT pattern non adjustable handlebars with Bowden 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 forks with brazed up fork bridge.

Extras

Footbrake on LHS and gearchange on RHS.

©  Colin Chapple