Skip to main content - The FREE technical site for Rudge Enthusiasts since 2001

1931 Dirt Track


Numbered 42996 to 46500 (approx) in Rudge sequence. Special speedway with curved front and rear downtubes. Un-strutted. Special kneehook lug. Steering head fork stop machined off. ). Bolt on seat stays with drawback type chainstays for rear wheel chain adjustment.


Front with special speedway hub with no drive dogs, rear dog drive type with large flange on drive side. 28x2 1/4”/2.3/8” beaded edge rims, chrome plated. Black spokes with NPB nipples.


Short black enamelled back and front ‘D’ section with cinder guard in front of engine.


Red enamelled parallel sided petrol tank fitted between frame tubes, with front recesses for fork clearance. Single Westwood type filler. Oil tank, red enamelled, larger than 1930 with single Westwood type filler and fitted with hand operated auxiliary oil pump feeding the rear of the engine.


Total loss version of the 1931 TT Replica engine - 4 valve 499cc with cast iron TT type open parallel valve cylinder head.18mm central plug and oval inlet port. 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. Round base to cylinder barrel with rear oil feed and 4 not 3 lower fin set using a 7.5" conrod. Special total loss timing cover fitted with 1928 type vertical metering ’pump’.


Webb speedway pattern.


Rudge countershaft.


Flange fitting Amal TT (2" centres) with twin float chambers and fast action twist grip. Cylinder head cast iron adapter, 2" to 2.2" (M3287).

Exhaust system

Two 1 1/2” pipes with the offside carried low beneath the timing cover and the nearside swept up to run above the top of the chains. Overall length similar to racing models.


Standard Fittings

Adjustable 1” handlebars, part chrome/celluloid with Rudge steering damper. Riveted angle and strip steel type centre stand.


Wired on type rims. Rudge Whitworth speedway countershaft. Magneto cut out (no extra charge).

© Colin Chapple


Login to Member Area

©  Colin Chapple