FOR some time past potential buyers of solo motor cycles have awaited with interest the advent of the new 3 h.p. Royal Ruby, which, manufactured throughout in the Ruby Cycle Co.'s own works (now very much more extensive than before the war), embodies many features of more than usual interest.
The frame is sprung front and rear by laminated leaf springs, the system of springing being somewhat unique. It is the result of several years' experiment on the part of the Royal Ruby designers. No doubt readers will recall the many references to Royal Ruby patents in this connection in The Motor Cycle, reviews of inventions which have appeared during the past few years. The system which has been finally adopted embodies springs which are centrally disposed, and can be adjusted to the weight of the rider.
In the eyes of the springs a roller is fitted instead of the more usual practice of using shackles. This construction considerably reduces the possibility of lateral play.
Another feature of the spring frame is that it can be converted in a few seconds into rigid construction by a patented locking device, although we do not think that this option will be used very considerably, as we cannot imagine any rider who has & really efficient spring frame wishing . to revert to the rigid type.
At its inner end the rear spring is carried on a saddle, which is fixed to the frame with two substantial bolts by means of a duplex structure formed of two steel pressings, which in turn are secured to the main framework by long bolts passing through lugs. At the upper end of this structure is a bearing supporting a duplex frame in which the spring is disposed. The outer end of this member contains the slides in which is the patented roller in the eye of the spring. Behind the bearing is linked an approximately vertical fork, which connects with the wheel fork near the wheel spindle.
The engine fitted is a single-cylinder four-stroke, having a bore and stroke of 74.5 and 80 mm. respectively, the capacity being 349 c.c. Side-by-side valves are fitted, and generally the unit follows more or less conventional lines. It forms a neat assembly with its silencer, magneto, and adjustable footboards. The exhaust pipe passes behind the magneto chain case, and the silencer is fitted directly beneath the magneto, and is supported on a platform, which is integral with the back portion of the magneto chain case. A large shield protects the magneto from mud, and is built in one with an undershield, having valances on each side of the engine.
A countershaft two-speed gear (another Royal Ruby patent), with handle-bar control, clutch, and kick starter, follows well-tried lines. This is located behind the engine, and is carried on a bracket which forms one side of a triangle in the frame construction. Immediately behind the gear box is the pivoting point of the rear wheel fork, which is supported on a long bearing, below which are the pivoting ends of the stand.
The front fork is apparently very light in construction, the frame of which consists roughly of two triangulated members connected at three points with the wheel pin to make a fourth. The motion is that of the parallel link type, and the tension of the long laminated spring is adjustable.
The transmission is by chain and belt, the wheels are 26in. x 2 1/2 in., and detachable mudguards are fitted which are 4 1/2 in. front and 6 1/2in. rear in section.
A long stirrup is used for the front wheel brake, in the ends of which the usual type of rim brake shoes are carried, and the rear brake is of the segment type, working inside the V belt rim.
The front member of the frame is of the Triplex construction, which is a feature of the 8 h.p. Royal Ruby.
The equipment of the machine includes British-made magneto, Amac carburetter, and Brooks saddle.
The Motor Cycle November 20th, 1919. p608