Honda GB30, becoming an outboard

Starting life as a small agricultural or industrial engine, the GB30 was a forerunner. In the mid-1960s, not many people would have betted that four-stroke outboards were going to take over the market

by Niccolò Volpati

The Sanremo music festival was won by Gigliola Cinquetti with“Non ho l’età (per amarti)”, the Italian government was led by Aldo Moro, Palmiro Togliatti died in Yalta and the Americans were bombing North Vietnam. It was 1964. In that same year, the first jar of Nutella came out of the Ferrero factory in Alba, and in Japan, Honda started producing the first-ever four-stroke outboard engine. Indeed until then, only two-stroke outboard engines had been sold.

The GB30, as it was called, wasn’t designed for use at sea, and didn’t look very much like other outboards. Instead of the traditional bar there was a kind of steel ring that went right around the radiator grille and then a lever for the accelerator. The steel ring was used to make the engine turn 360 degrees on itself. That way, even though it only had a single gear, it was as if it were fitted with a reverse. It was at the same time both simple and brilliant.

Its architecture was also simple, despite the fact that it was a four-stroke. The axle was horizontal, not vertical like all the outboards that had come before, and were to come after it. The reason for this can be given right away. It was not created for a marine environment. It was an industrial engine, used for rotary hoe, cement mixers or motor pumps.

In the mid-50s, indeed, Honda entered the machine sector for agriculture. It was done with small capacity engines, which were nearly all of between 100 and 200 cc. They were engines for gardening and irrigation. Then, in the 1960s, they considered modifying one of these, the GB30 itself, to become an outboard engine.

They were looking for a professional, rather than pleasure market. The GB30 satisfied the needs of small-scale Japanese fishermen. Japan is full of waterways, rivers and lakes. There were, and there still are, lot of fishermen. Back then it was a matter of single people who needed small boats, not companies organised for intensive fishing.

An outboard engine producing two and a half horsepower and which didn’t use much fuel, while being very dependable and quiet, that was what was required. The company decided to only invest in four-strokes. They had understood that was to be the direction that the market was to take. When in 1964 the first four-stroke for boats appeared, the founder, Soichiro Honda, made the famous remark: «Rice grows in water and fish live there; I don’t want to pollute what I eat».

And so the four-stroke was a choice, rather than a necessity. The company had two-stroke engines with which it was winning motorcycle championships hands down. There were actually three-cylinder 500s, and it would have been enough to convert them for marine use to produce outboards, even powerful ones.

But instead the decision was taken to go for cleaner and possibly more trustworthy technology. «The first GB30 were sold in the Venetian Lagoon area», says Mauro Bonaconza. Today he is involved in the car area, but he has been at Honda since 1985 and worked in all its divisions, including the marine one, which – together with other colleagues – he helped found.

He is considered the historical memory of Honda Italia, in part because of his passion for collecting artefacts, eye-witness accounts, photos and clippings. «There are probably a few GB30s still in use. Indeed there is no doubt as to how reliable they are. People who buy them say they are surprised by the low fuel consumption and how tough the propeller is».But the numbers were very low. To start with only ten or so came to Italy, and not by Honda’s choice. At that time there were still restrictions on imports. To import a GB30 and sell it in Italy, you had to get an import licence from the Ministry of Industry. It was the same licence as for ball bearings and for motorbikes of up to 380 cc. «So Honda thus often chose to import ball bearings or scooters, because they were more in demand», says Mauro Bonaconza.

The same licence was used for one product or the other. It was worse than with Donald Trump’s import duties. A duty is a partial limitation, because you have to pay it, but you can import as many as you like. The import licence imposed by the Italian government of the time, by contrast, set a limit of unit numbers that could not be exceeded. The licence was valid until the end of the ‘80s.

When it was finally scrapped, Honda was able to develop the marine sector without any restriction. «The marine range started in 1989 because until that time we imported and sold at most twenty or so outboards a year», says Mauro Bonaconza. In the meantime, the range had grown. There were the 2, 5 and 9 hp, all of them vertical-axle engines. And then, in 1990 came the 35/45 hp. At that time, the big thing was Johnson/Evinrude’s 737. It was a carburated two-stroke with power capped at 25 hp. The limit for people without nautical licences at the time was 25 hp, not 40 like today.

«When we arrived they all made fun of us», explains Mauro Bonaconza. «I remember the Genoa Boat Show in 1990. They had put us in a place with a lot of through traffic, since our stand was between the one selling focaccia from Recco and the visitors’ bathrooms. So there was a lot of visitor traffic. But we were at the end of a basement, a place that couldn’t have been more hidden away. Everybody said we would come to a quick end, because we didn’t have a 25 hp, and also because, they said, four-stroke engines weighed 30% more than a similarly-powered two stroke. My boss, Luigi Bigi, didn’t give up and decided to buy some digital scales. We weighed the competition’s outboard, and our own, and we discovered that there was very little difference».

But it wasn’t just unveiling the truth about weights that led to the success of the Honda outboard. The bet taken by Soichiro Honda was won in part also because of the North American market that had started to move towards sailing that was more environmentally friendly. It was at the end of the ‘60s that the first protected marine area in the world was created, in Biscayne Bay in Florida. And nobody wanted to see a stream of oil coming out behind boats any more. Four-stroke outboards were favoured more than anything else by anti-pollution regulations, first in the US and then in Europe.

(Honda GB30, becoming an outboard – Barchemagazine.com – March 2019)