A new cylinder with larger and neater finning is now employed on the 250 c.c. model.
Neat but effective enclosure has been adopted for the four valves of the 495 c.c. "Special" and "Sports Special"
With a view to eliminating piston slap an interesting type of Y alloy self-compensating piston is employed in the 495 c.c. "Special" and "Sports Special"
This nearside view of the 495 c.c. "Special" shows the massive cast aluminium chain case, the handle for the central stand and the long rear brake lever.
A new quickly-detachable rear wheel has been adopted for 1937
Rudge Enthusiasts Discover Many New Features in Range of High-Efficiency Singles: New, Light "Sports Special" with Tuned Engine.
"Sports Special" Mode1.—495 c.c. single-cyl o.h.v. Rudge; dry-sump lubrication; magneto ignition; all-chain drive; oil-bath primary chain case; 4-speed gear with foot control; fuel. 3 ½ gals.; 3.25x19 tyres.
Many important changes have been made to Rudge machines. Engines, particularly, have in many respects been completely re-designed. The "Sports Special" is a lighter edition of the famous "Special"; it has a higher compression ratio, polished ports, lighter mudguards, a high-level exhaust system, quick-acting twist-grips and a ribbed front tyre.
The four-valve head, which in this case and in the case of the "Special" has each set of valves side by side, has been modified, and it will be noticed that the head is finned vertically, while the valves are totally enclosed with a divided aluminium cover. Oil is pressure-fed to both rockers and the surplus is drained into the push-rod tube. A far neater appearance has been given to the cylinder by including holding-down bolts of a new design, by virtue of which the head may be removed sideways without disturbing the petrol tank. A feature of this and the "Special" model is a new self-compensating piston of Y-alloy, which allows smaller clearances to be used with a corresponding reduction in piston slap.
Coupled brakes operated by a long pedal are a feature of all models; the new tank shape should also be noted. The standard equipment includes lights, horn and, on 500 c.c. models, a speedometer.
"Ulster" Model—499 c.c. single cyl. o.h.v. Rudge; dry-sump lubrication; magneto ignition; all-chain drive; oil-bath primary chain-case; 4-speed gear with foot control; fuel 3 ½ gals. 3.00 x 21 (front), 3.25x20 (rear) tyres. Here is a machine which is world-famous. It incorporates all the improvements that have been adopted in other models, but the valve gear enclosure has been modified to accommodate the radial valves and centrally-placed plug.
Other points worth noting in the range are the well-protected rear chain, absorption-type silencers, quickly-detachable wheels, the central stand with its lifting handle, and the attractive black and gold finish.
"Rapid" Model.—145 c.c. single-cyl o.h.v. dry-sump lubrication; magneto ignition; all-chain drive; oil-bath primary chain case; 4-speed gear with foot control; fuel, 3 ½ gals.; 3.25 x 19 tyres.
This model has also been modified, and its two-valve head has a larger finned area and an altered induction port. A new 3 ½-gallon tank adds to the appearance and effective range of the machine, more suitable gear ratios are employed, and the wheel rims are black. Such items as coupled brakes, lighting, and a pillion seat are included, but on this model a speedometer is not a standard fitting.
Australian Cycling & Motor Cycling, January 20th 1937. Trove NLA
