FOLDING MOPED… | MODEL CONSTRUCTION

Not once I tried to build a simple convenient and compact micromatic. However, after building and testing several cars with the engine D6 revealed the shortcomings of the stereotyped repetitive on all of them: awkward pose (especially for tall riders), no auxiliary pedal drive, the need to start, as they say, “push”, small trunk… of Course, all this is offset by the small size and low weight machines.

After the purchase of a folding bike MMVZ Minsk has a new idea to install the engine D6. It promised a number of advantages. First of all this bike quite a comfortable fit; the ability to vary the position of the seat and the steering wheel (as per child and adult). A normal pedal drive and optimally selected gear ratio of the transmission from the engine to the sprocket allowed the harmonious combination of muscular strength and small power D6, getting a good dynamics of acceleration and high top speed (50 km/h) required to move in traffic. The bike also has a good trunk, which can carry a variety of goods.

Of course, the main task was installation of such engine, which in any case would not interfere with the folding of the bike. Note that when folded, the scooter has overall dimensions of perhaps even less than well-known microvesicle.

Engine mounting D6 on a folding bike “Minsk”:

1 2 — the upper attachment point of the plant, 3, 4 — average attachment point of the plant (elongated threaded pin and a collar), 5 — motor base, 6 — strip (rubber), 7 — bottom mount power plant, 8 — plate adapter mounts to the muffler.

I’ve tried different ways of mounting the engine: on the trunk, on the front fork. But in the end chose the classic layout: with the engine under the saddle. Any welding on the frame to produce was not required, had to make only a few details, including the three simple clamp. Note that at any point the engine can be easily removed.

The engine is attached to the base, and it, in turn, on the frame. The base is welded from steel sheet; it includes the wall and two ribs, the backbone node, and also clamps for attaching the base to the frame and boss pin to ensure correct installation of the motor on the base. Boss is a sawn piece of pipe of suitable diameter. Wall and of the ribs cut from steel sheet with a thickness of 3,5…4 mm. the Wall is first bent along the dotted lines of the scan, after which the angles shown on the drawing, are adjusted in place on the motor and frame.

The ground under the engine D6 to install it on the bike

The ground under the engine D6 to install it on a Bicycle “Minsk”:

1 — ears of the upper attachment point of the plant, 2 — ribs, 3 — bolt bottom mount power plant, 4 — boss-latch, 5 wall.

The fixing clamps of the engine.

At the base of the slot to pass the left rear stud fastening D6, which is replaced by more long — 50 mm (due to the large diameter seat tube bike).

For this reason, regular rear right fixing pin motor is transferred to 15 mm to the right (in the crankcase hole is drilled and tapped M6). The adapter is fixed to the frame clamp with the rubber gasket (a strip of rubber from autocamera), which is tightened with a bolt M8. On top of the base can also be attached by a clamp and two bolts M8. And on the studs of the engine fits the cowl, fixed nuts M6.

The muffler normally. You only need a little to straighten the exhaust pipe (heat it in the flame of a blowtorch) to fit in place. The lower end of the muffler is mounted behind the ear fencing chain (on the carriage) through the small plate, the size of which matched in place.

Sprocket driven (Z=22) — from a sports bike “Sputnik”. With such gear the bike moves steadily at a speed of from 15 to 50 km/h, however when starting off and accelerating the rider and the need to work the pedals.

Mount conventional sprockets: half rings to the hub of the rear wheel of the Bicycle. To protect the spokes and prevent jump-out of the chain between the sprocket and the spokes inserted disk from two-millimeter steel sheet. The outer diameter 140 mm inner — diameter of the sleeve.

When mounting the chain drive may need to be slightly curved inclined tube the rear fork. To do this, remove the wheel, put bike on stand (wooden bars) and two or three blows through the wooden prorate is provided by a slight bend of the tube, so that the chain does not touch her.

Controls regular without alterations, located on the steering wheel. Fuel tank — like “droplet”, but you can use another suitable container. Suspended tank on seat tube.

To enhance the security of riding the Bicycle is equipped with duplicate manual brake operating on the front wheel. The staff added additional, attached on the back side of the front fork an elongated hairpin. Both brakes are controlled with a lever on the steering wheel to the right.

The chassis of the bike is not fine-tuned, no power-UPS of its design has not been done. In 8 years of operation, the total mileage amounted to more than 10 thousand km on asphalt and dirt roads, and the total “load” reached 140 km. Destruction of elements of the frame and weld was not observed.

The changes affected only tires. On top of the regular tires was wearing a “bag” cut from an old tyre: thus, the rear wheel came with a deep tread pattern, which is useful when moving on the ground. When tire wear was a big, on the front and rear wheels were put on two tires down the old, top new. In this case, improved shock absorption on the bumps.

In conclusion remains to add that the bike was used for long journeys between cities, and in everyday driving. The design turned out very “robust” and reliable.

Here’s a folding moped I propose to the readers ‘ attention. I am sure it will be useful to many, especially beginners, primarily because of its simplicity and reliability. (By the way, my car is easier than Pankov, who described it in the “M-K” № 3, 1985.)

V. KOROBOVSKIY, engineer, Krasnoyarsk

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