Description
Rudge 1939 “Ulster” 499 cc four-valve single frame # 65263 engine # 3142
The Rudge-Whitworth company was an established bicycle factory that entered motorcycle production in 1911. Their first machines were 499 cc IOE singles. They developed the famous Multi gear, with a possibility of up to 21 gear positions. In 1924 the factory introduced a new range of four valve singles. In 1928 Graham Walker managed to win the Ulster Grand Prix on a Rudge, after a heroic handlebar-to handlebar battle with Charlie Dodson on a Model 90 Sunbeam. Since then the sporty Rudge models were designated “Ulster”. Rudge used several layouts for its 4 valve models and from the 1931 model range on they settled for the semi-radial arrangement of parallel inlets (in a flat head surface) for deep breathing and radial exhausts (in a part spherical surface) for cool running. At the same time plug size was reduced from 18 to 14 mm to allow more metal between the hole and the exhaust seats. This layout proved very successful and was retained till the end of Rudge production in December 1939. From 1934 the Rudge Ulster was equipped with an aluminium bronze cylinder head. An important new feature from 1937 on was the enclosure of the valve gear by a neat aluminium cover; also a larger-capacity petrol tank was fitted with a content of some 3½ gallons (15 litres). For the 1939 range no major improvements were announced, the 1939 brochure commented: “We are averse to the policy of making purposeless changes for the sake of change only, and consequently the well- tried Rudge range is offered for 1939 with no major alterations, although certain technical modifications resulting in improved performance have been effected.”
The Ulster has bore x stroke dimensions of 85 x 88 mm, two parallel intake valves and two radial exhaust valves fitted in an aluminium bronze head. Inlet and exhaust ports and combustion chamber are polished and the valve gear is completely enclosed and pressure lubricated. The big end bearing is a three-row roller construction with duraluminium cage. Cams are high-lifting and racing valve springs are fitted. Electrics are Miller with an 8 inch headlamp. Brakes are proportionally coupled with front drum diameter of 7½ inch and rear drum diameter of 8 inch. A very practical feature is the centre stand with patented easy to operate hand lever.
This Ulster was bought around five years ago by the former owner. It had been restored at some time in the past but it was decided to give the mudguards and petrol tank a new shine in BMC Damask red colour. A technical check-up resulted in a number of jobs being undertaken: the magneto was rewound, carb, forks and clutch were rebuilt, regulator was refurbished and new Cox & Turner piston was fitted. The Ulster also got a new battery, tyres and tubes. With sundry other improvements and new parts in all around 2000 euros has been spent, not including the paintwork. The machine is a good runner and comes with current registration. Video: https://youtu.be/ta7jWZwCmyI