A.J.S.
A 5 h.p. twin-cylinder A.J.S. machine is to make its bow to the public at Olympia. This is quite a new type, and presents several novel features. The twin-cylinder engine has a bore and stroke of 70 x 82 mm. respectively, and has its valves lying side by side and carried in detachable cylinder heads.
These heads are held on by a forging which bears on a central boss and is held down by two swing bolts (see sketch). A dowel pin is placed on one side, so that the head can only be put on in the correct position. Separate cams operate the exhaust valves, while one is made to serve both inlet valves. A U.H. magneto supplies the current, and an Amac carburetter lies between the cylinders. A simple counter-shaft two-speed gear on the lines of this year's 2½ h.p. A.J.S. gear, but enlarged and simplified, is employed, in conjunction with a clutch consisting of a single plate carrying cork insets, gripped by a plain steel plate on either side. A new feature for this machine is the simple kick down starter. Chain drive is employed throughout, the chains being amply protected from mud by metal shields.
The gear is actuated by a lever carried on a quadrant which is brazed to the top tube. The clutch lever lies on the left handle-bar. The A.J.S. gear was described in a recent issue, so it is only necessary to repeat that it, with the clutch, is particularly easy to dismantle, and the merest novice could make no mistakes in re-erecting it. The pistons have two top rings and oil grooves cut in them right up to the gudgeon pin boss. The gudgeon pin is held in position by brass washers.
The 1912 frame is fitted with a dropped top tube, and the tank has all the fittings on one side, so that it is very easy to remove in case of damage. A very neat toolbox is carried in a steel case below the carrier. The back of this case forms the number-plate, while a strap fixed to the carrier descends and acts as a mudguard support. The foot brake pedal is carried on a separate lug, and the shoe acts above the chain stay, and is pivoted so as to come into action evenly. Druid spring forks are employed, and a neat head lug is fitted with provision for a lamp and generator. All the above remarks apply to the 2½ h.p. A.J.S. with the exception of those concerning the engine, which in this case is a single-cylinder 70 x 82 mm. Both these models are well made and neatly finished, and the 2 1/2 h.p. has performed extremely well in this year's trials.
1911 Olympia Show - The Motor Cycle November 16th, 1911. Page 1210
A.J.S., No. 128.
A. J. Stevens and Co., Retreat Street, Wolverhampton. - Three of these models are shown. They are this year fitted with footboards, and the brake is operated by the heel. The change speed lever is on a lug brazed to the top tube, and a foot starter can be fitted as an extra. Another 2½ h.p. model is shown with a belt drive.
There are two models of greater power. These models include a kick starter as a standard and 2½in. tyres. Both models are fitted with neat petrol primers and the well-known A.J.S. friction clutch; they also have Druid forks. The arrangement of the toolbag is especially neat. This slides bodily into a metal case placed under the carrier, which also supplies the place of a number plate. These machines were fully described in our last issue.
1911 Olympia Show - The Motor Cycle November 23rd, 1911. Page 1257
