A duplex frame miniature two-stroke the Grigg - a 161 c.c. engine and Sturmey-Archer two-speed gear are fitted.
Simple framework is an all-important point on such a design as the Grigg.
An Ultra Lightweight.
The 1¾ h.p. (161 c.c.) Grigg Two-stroke Miniature Motor Bicycle.
THE makers of the Grigg miniature motor bicycle have hitherto specialised on a machine of the scooter type, but they have now adopted a policy which this journal predicted would be come general after, the first flush of the stand-up scooter boom had subsided.
Although the scooter will not be discontinued, the Grigg Motor and Engineering Co., of Winchester Road, Twickenham, have incorporated the same engine in a simple low-built duplex frame of motor cycle type.
A two-speed Sturmey gear box, with clutch and kick-starter, is incorporated, the transmission being by chain and belt. The frame is constructed largely without lugs, the joints being welded, and the construction is light.
Girderless Druid forks carry the front of the machine, and 24x2in. wheels are used, tyres of this size being no doubt ample for a machine of such small engine capacity. The two-stroke engine of 57x63 mm. bore and stroke is well designed, and has a compression release which connects up witli the exhaust system ; the cylinder ports are bridged, so that unpinned piston rings may be used without fear of the ends springing open into the port orifices.
From many points of view the Grigg is a machine laid out on lines of great promise, and the straight tube duplex frame should give strength with lightness and at the same time permit a saddle position low enough to suit the short person. Marketed at a low price, should be ideal for runabout work, in addition to being capable of long journeys.
The Grigg is certainly of a type deserving encouragement. Having all the handiness of a "scooter," it nevertheles; embodies well-tried and approved motor cycle design. The fact that scooters made their riders too conspicuous was frequently overlooked.
Sources: The Motor Cycle 1921.
