What makes the N-series such an important car in the history of Honda?

The N-series was a car of many first times:
1) The N-series was the first Honda car produced and sold in high volumes
Before the introduction of the N-Series the only car Honda sold was the beautiful S-Series small sports car. In 1966 Honda produced only 3.209 cars. In November 1966 Honda showed the N360 for this first time to the public. The N-Series went on sale in March 1967 and proved to be an instant hit. Almost immediately following the launch the N360 became the best selling Kei mini car of Japan. The N-Series boosted Honda car production to over 200.000 units a year. Finally 1.165.144 units of the N-Series were produced in only five years!
2) The N-series was the first Honda car with success in export markets.
The N360, but particularly the N600, was exported to the entire world. The main export market was the United States.
3) The N-series was the first Honda car to be produced outside Japan
In Taiwan a joint venture of Honda with Sanyang, selling scooters and motorcycles under the brand name SYM, started assembly of the N600 in 1969.
4) The N-Series was the first car you could buy at a Honda CAR dealership
When Honda introduced the N-Series it only had a motorcycle retail network. Many N-Series have in fact been sold by motorcycle dealers. But the Honda N-Series meant the start of Honda building its car dealer networks in Japan, the USA and Europe. The success of the first Civic, introduced in 1972, was another strong stimulation for this effort.
5) The N360 was the first Honda and the first Kei Car with automatic transmission
Honda introduced the Hondamatic automatic transmission on the N600 in 1969.

What was the source of inspiration for the N-series?

Mini 850

The main source of inspiration for the N-Series must have been the Austin Mini 850 as there are some very strong similarities. The concept of the body has the same basic shape, nearly similar dimensions and also two doors and a small hatch. Both cars featured front wheel drive, a transversal engine mounted in front of the car and with four-speed manual transmissions in the engine sump. The main differences between the two cars was that the N360/600 featured a twin cylinder with air-cooling while the Mini 850 featured a four cylinder with water-cooling. The Mini had a 850cc cast iron block while the N600 had a 598cc alloy block. The Honda engine used a roller bearing crankshaft whereas the Mini conventional plain main bearing. It seems that Soichiro Honda took the Mini 850, the brainchild of Sir Alec Issigonis, and modernized it to his own ideas, with the main difference being making it air-cooled. Interesting is that the Mini, which was introduced in 1959, seized to be exported to the USA in 1967, so these two cars never competed with each other in the USA, the N600’s main export market.

What makes driving the N-Series so much fun?

The fun comes from the combination of a small highly efficient engine with a very light car body. It gives the N600 a power to weight ratio of 13.1 kg per horsepower. This is close to the 11.3 kg per horsepower power to weight ratio of the Honda Jazz 1.2 90Hp. This is the smallest Honda currently available in Europe.
The N600 certainly does not have a high top-speed but between 0 and 80 Km/h it accelerates quite rapidly and is lots of fun.
Honda did everything to make the car as light as possible. First of all the car is light because it has very compact dimensions and because it has a front-mounted engine supplying direct power to the front wheel drive. Many parts such as the rear hatch, the rear parcel shelf and the dashboard were made from plastic. No complicated ventilation system was constructed. Simply by opening a valve in the interior in front of the front doors fresh air would enter the car. Obviously this means that when you stand still in front of a traffic light on a hot day the temperature rises quickly. Then the N600 engine is also very light weighing only 96.5 kg. The N360 engine is even lighter weighing a merely 87 Kg.
The engine, transmission and differential were constructed as a single unit. It was a twin cylinder made from alloy. That means it was not made from cast iron which was common in those days. Because of the air-cooling the engine block did not have to accommodate water circulation and also there was no need for a heavy radiator.

Does the N-series have a motorcycle engine?

Some characteristics of the N600 engine are similar to those of motorcycle engines in these days. Think about the air-cooling and the integration of the gearbox and the engine. However, there has never been a Honda motorcycle equipped with the N360 or N600 engine. However, according to the book The Honda Story by Ian Falloon Soichiro Honda did consider using the N360 and N600 engine for a motorcycle. In February 1968 several managers of American Honda visited Japan and convinced Soichiro Honda to develop a new 750cc four cylinder engine instead. In 1969 this led to the fabulous CB750, a milestone in Honda’s motorcycle history.
This motorcycle provided performance, refinement, civility and reliability previously unheard of in a mass-produced machine. The CB750 effectively killed the British motorcycle industry and forced other Japanese motorcycle manufacturers to abandon two strokes, twins and triples engine concepts.

Why did Honda use air-cooled engines for the N-series?

In 1966, when Honda announced the N-series, air-cooling was the direction chosen in the strategic plans of Honda. At that time air-cooling was popular for use in passenger cars, especially in Europe. Soichiro Honda believed that air-cooling was preferable above water cooling as he considered air-cooling more efficient. He also chose air-cooling for his racing cars. In 1968 Honda introduced a new air cooled F1 racing car, the RA302. It is important to note that in that same year Ferdinand Piech developed the incredibly successful air cooled Porsche 917, which won the 24 hours of Le Mans in 1970 and 1971. Unfortunately Honda was not so successful. When in 1968 French driver Jo Schlesser died from an accident on the circuit of Rouen a shocked Soichiro Honda decided to withdraw from F1 racing.
In October 1968 Honda introduced the 1300 coupe, followed in May 1969 by the sedan version. This car was the largest car produced by Honda at that moment. Soichiro Honda had a heavy personal involvement in the development of this car. The 1300 was an engineering triumph but at the same time a commercial failure. The investment to develop the highly advanced air-cooling system and also the production costs were so high that its profit was very small. Around this time the government of the United States, Honda’s priority export market, announced the Clean Air Act which included tough emission standards. Soichiro Honda started having discussions with his engineers who believed that only water cooled engines could meet these emission standards. But Soichiro Honda continued to believe in air-cooling. Soichiro Honda finally gave up his resistance to water-cooled engines when Takeo Fuijisawa, Honda’s vice president, made it clear to him during a diner that the company had no future when choosing for air-cooled engines. Soichiro Honda then finally gave in. When the next morning he told his engineers at a meeting that he would support the development of water-cooled engines he received a warm applause. The Honda cars which were introduced from that moment, the Life and the Civic, all had water cooled engines.