Honda Monkey Z-Series

The Honda Z-Series refers to the lineage of mini bikes manufactured by Honda Motorcycles. Though Honda's official model designations are typically Z50A, Z50J, Z50M, Z50R and ZB50, they are more commonly referred to as the "Monkey" or "Gorilla" because of the way people are said to look when riding one of such bikes. Sales of the bike began in March 1964 with the Z50M model.

Most Z-series bikes are small, light, collapsible motorcycles made for convenience and ease of transportation. Their outstanding feature is a 50 cc four-stroke engine with an over head camshaft. Some have a centrifugal clutch and a three gear manual transmission, while others have conventional manual clutch and a three- or four speed gearbox.

The original model of the Honda Z-series was originally produced as a children's ride at a Japanese amusement park, but was eventually refined and put into mass production, hitting the European market in 1967.

Since then Honda has produced a wide variety of Honda Z-series mini bikes, with annual model updates still in effect. Starting from 2008, the well-known 50 cc engine will be adapted and fitted with an injection kit instead of carburetor.

Monkey bike is the name given by Honda to one of their small, low-powered motorcycles introduced in the 1960s. The first Honda Monkey was the 1961 Z100. Later Monkeys were designated Z50, such as the Z50A(US), J, M, R(US) and Z.

These vehicles all had a 4.5-horsepower (3.4 kW), 49-cubic-centimetre (3.0 cu in) single horizontal cylinder four-stroke engine, and a seat height of less than 22 inches (560 mm). The very first Monkey bikes did not have any suspension but the front forks was soon added. By 1974, when the Z50J was introduced (US 1972 Z50AK3), suspension had been added to the rear as well. The first Monkey bikes had 3.5-by-5-inch (89 mm × 127 mm) wheels, but later models had 3.5-by-8-inch (89 mm × 203 mm) wheels.

Numerous similar designs predate the Honda model, notably the World War II Welbike motorcycle used by parachutists. However it wasn't until the introduction of the Honda Monkey bike that this type of design became commonplace.

The Honda Dax model is generally not considered a Monkey, but rather a bigger, two-seat variant, with larger 10-inch (250 mm) wheels and usually a larger engine. The Dax models have a monocoque stamped sheet-metal frame. This also houses the fuel tank, battery and wiring loom.

Monkey milestones

1961 Z100

First model – made for use at amusement parks, with 5 inch wheels, rigid suspension, foldable handlebars and Super Cub (C50) 3.1kW OHV 49cc engine. Backbone frame, triangular tank.

1963 CZ100

First road-going model – exported to North America and Europe.

1967 Z50M

First model sold in Japan – with ‘fold-down’ seat, handlebars and pegs to fit in the back of the car (the new fuel cap also added to prevent leaks when stored on its side during transport). Centrifugal clutch.

1969 Z50A

Telescopic front fork, 8” front wheels, low slung exhaust and indicators for the first time.