Tiny Moped

The compact moped I designed, unlike production models, fits freely in a passenger elevator. That is perhaps one of its main advantages, since the two-wheeled little machine (which, incidentally, reaches the same speed as the “Riga-7”) can also be “parked” on the balcony of a city apartment.

The moped frame is taken from a children’s bicycle of the “Renak” make, with the stock drive sprocket, bottom bracket, pedals and cranks. The rear-wheel fork is reinforced with a stay, and extra frame stiffness is given by a horizontal tube between the saddle and the handlebars.

The front-wheel fork is telescopic, with spring suspension (the springs and struts are taken from a motorized bicycle). The handlebars are from a standard racing bicycle; the throttle and clutch cables are routed inside the bars.

The engine is a D-6. The drive chains are enclosed by a light cowling that is fastened to the frame with a single screw. The cowling shape leaves access to the spark plug, the carburetor button and the air filter.

The wheel rims are from a children’s scooter. The rear axle is a bicycle axle with a coaster-brake hub. An 18-tooth sprocket is mounted on it on splines. For strength the number of spokes had to be doubled (32 instead of 16), using shortened moped spokes of Ø 3 mm. The same spokes were fitted to the front wheel in place of the stock ones.

A few words about other parts of the mini-moped. A “Riga-7” saddle gives a comfortable riding position. The cylindrical fuel tank of 2.5 L capacity is homemade. It is held by a single hinged bolt. A roller for tensioning the pedal-drive chain is mounted on the frame stay. Under the saddle (at the moped’s center of gravity) there is a carrying handle.

The tires are from a children’s scooter. To reinforce them, an identical tire is glued inside the main casing, turned inside out. Such a “sandwich” can be bonded with 88N adhesive or a mix of 100 parts thiokol and 30 parts hardener. The freshly glued casing with the inner tube is fitted to the rim, inflated with a pump and left to dry for two days.

“M-K” 6’78, M. VYSHINSKY