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What the Japanese Bayberry Trees Have Seen Stories from the Early Years of Yamaha Motor

Introducing the stories behind Yamaha Motor's technologies.

41The Miyaguchi Test

When recalling and talking about what it was like back when Yamaha Motor was founded, most people today are surprised at the large number of rarely heard of topics and events that come out in the conversation, and one of them is definitely the Miyaguchi Test. Quality control wasn’t nearly as thorough in those days as it is now, so the only way to check and guarantee the performance and functionality of a freshly assembled bike was to take it for a ride.

We continued doing the Miyaguchi Test for quite a while after the company was founded. Basically, every machine that was completed at the Hamakita Factory had a temporary number plate attached and a rider from the Inspection Department would set off from the factory to give it the Miyaguchi Test. This was about a 7 km ride to Miyaguchi northwest followed by an uphill section, and a straight road at the top. After riding 8.6 km the rider would return to the factory.

Machines would typically show signs of piston seizure or other problems during the test. It was only after making repairs and adjustments that a bike was shipped out. The process made the costs we spent on inspections a hefty sum, but we really had no choice because our quality control was still in its infancy in those days.

The Miyaguchi Test was still in use in 1956, the company’s second year and when the single-cylinder 175cc YC-1 was released. One of the problems with the YC-1’s engine design was that it would often generate noise because of piston slap due to excessive piston-to-cylinder clearance. To get rid of it, you have to reduce the amount of clearance but when you did, the piston would quickly seize. Because the cam-ground shape of the piston was not always accurate—something vital for 2-stroke engines—the Miyaguchi Test was an essential step in our inspections.

For example, in durability tests at full load on a chassis dynamometer, the YC-1’s engine would seize up in only two or three minutes. But machines from other manufacturers would go for 30 minutes or more before seizing, so we worked feverishly to find a solution. But the ideas the engineers came up with to fix the problem were usually substandard, often earning the wrath of President Kawakami.

Compared with the YA-1, the YC-1 had more power and could hit speeds up to 100 km/h, so a long period of trial and error was required to iron out the problems. In the end, it took more than a year to eventually resolve the issues and ensure consistent quality by changing the piston’s alloy, structure and more.

The Miyaguchi Test had played a big role in our quality checks and model development, but on March 1st, 1957—after two years of use—the Miyaguchi Test came to an end.

42Production and Sales of the YC

Production of the YC-1 began in February 1956, but due to the aforementioned problems, full-scale production wasn’t possible. However, after intense effort on our part we were able to ready the first 50 units for shipment.

When we displayed the YC-1 for its formal debut in late April at a motor show held at Hibiya Park in Tokyo, it garnered rave reviews and we were there ready to take purchase contracts. We had customers write in their names on a gold-colored piece of paper to boost interest. In other words, our launch strategy was right on target. The wall behind the display stand was soon covered with gold-colored purchase orders for the YC and we had our hands full that day, indeed! Surprised by the unexpected popularity of the bike, our production demands only increased. The number of people saying we didn’t need to keep the YA-1s coming off the line and to just focus on getting the YC-1s out the door as quickly as possible grew by the day.

The problem was, the production arrangement we rushed to put together wasn’t at all capable of meeting the number of orders we had. We also needed more hands, so to deal with the problem, we set up a system to have our dealers send us personnel to train while they helped assemble the new machines. The dealerships also wanted to get as many YC-1s ready as possible and—as if competing amongst themselves—sent support personnel to us at the factory. Eventually, 20 to 30 of them came to work full-time at the factory, making not only a significant contribution to Yamaha’s production capacity but also fostering a strong bond between the people at the factory and the mechanics and service staff at the dealers.

That spring was when the first round of employees—there were 11 of them—we had hired as mechanics arrived. We had carefully selected them from all across Japan, so they were definitely sharp but they were still fresh out of school and overly energetic. I was in charge of their training and often had a lot of trouble dealing with them. Because there wasn’t enough food at the workers’ dormitory and they were often hungry, I regularly bought them anpan (bread rolls filled with sweet red bean paste) out of my own pocket. I later heard that it was something they all remember with fondness.

Though we didn’t realize it at the time, that anpan helped forge strong personal relationships. Seeing many of them now working in responsible positions within the company makes me happy as if they were my own achievements.

Their on-the-job training continued until early July, but it was at that juncture that problems inside the YC-1’s mufflers were discovered. We suspended the training so we could service the bikes that had already been sold, and sent the trainees off across Japan service tools in hand on July 13th to fix these problems. That was how Yamaha’s first service personnel left the nest!

43A Step Toward Expansion

In January 1956, the Yamaha Motor Hamamatsu Research Institute was established within Nippon Gakki to consolidate the departments for motorcycle development and engineering with Takai-san heading operations. He was also in charge of the engineering department for designing new products together with acting department manager Shinichiro Takeuchi.

On March 16th, the company bought the grounds to the south of the factory from Enshu Fibers. This expanded the factory grounds to today’s southern fence, and we built a new gate on that end and designated it as the factory’s main entrance. We remodeled parts of the original wooden factory buildings that had been purchased and built offices like a barracks, but because the floors were wooden, employees removed their shoes and wore slippers when working there. This was the company’s first-stage expansion.

Map of the main facilities at Yamaha Motor Co., Ltd.

On April 28th, a new materials department was established as procuring production materials became more important. During April, we shipped a total of 605 YA-1s and YC-1s, but because the president had strongly demanded a monthly production scale of 1,000 units, we were constantly reviewing and revising production plans and implementation measures. By around May the number of employees had grown to 253, and we produced 411 YC-1s and 310 YA-1s for a total of 721 units that month—more than double the previous year’s production.

Yamaha dominated both the 125cc and 250cc classes at the 4th Mt. Fuji Ascent Race

On July 9th, the 4th Mt. Fuji Ascent Race was held. The Hamamatsu Research Institute had taken the lead in building racebikes and preparing for the event. Because it would be the debut race for the YC-1, Yamaha would be contesting two classes. The 125cc to 250cc class was won by Yoshikazu Sunako with time of 22’33, followed by Shigeru Konagaya, Mutsuo Shimora, Yukio Hoshino and Hiroshi Taniguchi, all on Yamahas. The under-125cc class was won by Taneharu Noguchi with a time of 24’37, followed by fellow Yamaha-mounted Osamu Mochizuki, Teruo Mibu, Shoichi Miyashiro, Toshio Tsukamoto and Mitsuru Masuko. In other words, the race was completely dominated by Yamaha. I think this performance firmly established our reputation as race winners; it was no longer disputable.

In August, work began on building a new machining factory about 76 × 22 m2 in size. It was completed in December and went into operation in January 1957. Today, this is where the central section of the Hamakita Factory’s No. 3 building is located. Our production numbers gradually increased; in September, we built 289 YA-1s and 791 YC-1s for a total of 1,080 machines. We had finally surpassed the 1,000 unit per month target we had had for so long. At the time, a monthly production quota of 500 units was considered the break-even point, so we had finally reached a level where there was real hope for the future of the company. This is when those involved and our affiliates started gaining confidence in our endeavor.

The company cafeteria at the time

On October 2nd, the company made its initial public offering. The monthly salaries for new hires were as follows: 2,500 yen for junior high school graduates, 3,700 yen for high school graduates and 5,750 yen for college graduates. We also had small, bi-annual pay increases to enhance worker satisfaction. In his concern for the wellbeing of his employees, President Kawakami established a company cafeteria in 1957 and later instituted and distributed worker uniforms to everyone, making Yamaha one of the first business organizations in Japan to do so. By continuing such initiatives to improve the work environment, the grim and often-frowning faces of employees that were so common to see when the company first began its adventure gradually began to brighten.

44Our First 250cc 2-Stroke Twin

Designers creating a clay mock-up of the YD-1

In 1956, while the factory was busy producing the YC-1, the Hamamatsu Research Institute had planned and begun designing a 250cc 2-cylinder motorcycle, and work on building the prototype was soon underway. At the time, one of the most popular motorcycles from overseas was the 2-stroke parallel twin Adler MB 250 from West Germany. We were planning to build our bike using it as a model, but the chassis engineers as well as the designers from GK really wanted to create something unique on their own with the bike and wanted the design freedom to do so. President Kawakami accepted their request and the end result was the YD-1.

The design of new machine represented a dramatic step towards Yamaha originality—benefitting from all that was learned with the YA-1 and mastered with the YC-1—and was a truly inspirational creation from GK. The ideas and image for the bike came first with the engineering and design following to make it a reality. The first time the YD-1 was shown to me, it honestly blew me away. It was so unique; the dynamic, flowing lines made it look like it was in motion even when it was standing still. Because it also had numerous new devices and technologies we were trying for the first time, revisions and improvements continued even after production had begun.

President Kawakami on the YD-1

The first YD-1 rolled off the production line on February 11th, 1957. As was the tradition, President Kawakami personally stamped “No. 1” on its chassis. Two years earlier on the same day, a similar ceremony was held for the first YA-1, but this was almost certainly a coincidence. President Kawakami also stamped the engine number on this machine, but as circumstances changed in the years ahead, the YD-1 ended up as the last bike for which this ceremony was performed.

Then on February 22nd, President Kawakami set off for Tokyo together with Executive Officer Ono and Department Manager Takeuchi on three YD-1s to present the bike to the press. They departed Nippon Gakki’s headquarters at 9:10 in the morning, arrived at Numazu near the base of Mt. Fuji at 3:00 in the afternoon and spent the night at the town of Izunagaoka.

President Kawakami on the YD-1 with his group on their way to Tokyo

The next day the trio arrived in Tokyo at 4:20 that afternoon after riding 287 km in total, and the YD-1 made its formal debut in front of the media. Although Yamaha enjoyed tremendous success in racing, the lack of variety in our lineup was considered our weakness. But we had just introduced a bike with a 250cc twin-cylinder engine in only our third year in business, so I suppose it was only natural that this caused a sensation.

Full-scale production of the YD-1 began in March, with 14 units produced. This figure steadily grew to 100 units in April, 303 in May, 528 in June, and 683 units in July. However, we would face serious hardships with quality control on the way. When we first began sales, the dealers were very enthusiastic and would come to the factory with wads of cash and beg us to somehow allocate some YD-1s to send to their showrooms, putting me in a difficult but humbling position.

However, after a few months customer complaints about engine problems began to increase in frequency and we needed to quickly make drastic countermeasures. Hidden behind the seemingly strong sales of the YD was something worrying that we were about to discover.

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