The Road To Making Honda’s Challenge of Winning the Trial Championship a Reality - First era 4-stroke, first generation (air-cooled / twin shock) Honda’s Unwavering Passion for Motor Sports Heralds First Golden Age

The Road To Making Honda’s Challenge of Winning the Trial Championship a Reality - First era 4-stroke, first generation (air-cooled / twin shock) Honda’s Unwavering Passion for Motor Sports Heralds First Golden Age

Chapter 1 Honda makes Japan’s first trial bike, venue, and also a culture

It all began 48 years ago, when Honda announced Japan’s first trial bike, the BIALS TL125 (4-stroke / twin shock) at the 1972 Tokyo Motor Show. Ten years later, Eddy Lejeune rode his Honda RTL360 factory bike (4-stroke, water-cooled / twin shock) to Honda’s first Trial World Championship.

Honda not only continued its challenge to win the world championship; it brought trials to Japan, developed and sold many trial bikes, prepared the venues and trials instructors, and organized attractive events, laying the groundwork for the trials culture to grow in the country.

In other words, Honda worked hard to make trials a popular motor sport in Japan, and in doing so, Honda challenged the world, and with its high level of engineering, won the world championship three years in a row.

1. The original production bike: Honda BIALS TL125

The Honda BIALS TL125 went on sale in 1973.

The model name “BIALS” (BIKE + TRIALS = BIALS) was significant, as many trials enthusiasts in Japan did not ride domestically-made trial bikes, but modified off-road bikes, or even imported trial bikes instead. For those riders, the TL125 was the locally-produced trial bike they were waiting for, and it had a displacement and compact chassis that was well-suited to the trials novice. By adding safety components, the TL125 turned into a street-legal bike that could go touring to the mountains, without the need of being transported by truck. If 125cc wasn’t enough, its engine could be replaced with a larger one.

Honda also set up a “Motorcycle Recreation Promotion” division, which set up Honda Trials Parks in over 20 locations nationwide, including the Suzuka Circuit in Mie.

Between 1973 and 1975, other Japanese manufacturers also started producing trial bikes, and soon all four bike makers had their offerings on the market. In 1973, the Motorcycle Federation of Japan (MFJ) organized the first All Japan Trial Championship at the Hayato River trials course in Tsukui, Kanagawa, and with every manufacturer vying for the inaugural All Japan championship and an expanding trials population, this period became known as Japan’s first trials boom.

The TL125’s catalog at the time said, “A true trials machine is an excellent road machine,” and had an introduction to British trials king Sammy Miller, who signed a contract with Honda and visited Japan to hold seminars. In 1975, Honda released a higher-grade model to the TL125, the track-only BIALS TL250. The following year, the company added the TL50, an easy to ride scooter, to its lineup.

The HondaTL125 endeavored to prove itself overseas as well, racing in the Scottish Six Days Trial (SSDT), held over six days over some of Scotland’s most inhospitable terrain, making it the world’s most grueling trial event. Began in 1909, the SSDT not only has a century-long history, but its emphasis on testing endurance made it an event that if won, proved a rider’s and bike’s supremacy. In 1973, three riders (Toshiki Nishiyama, Yasuo Manzawa, and Shozo Narita) competed in the event on their TL125s, and completed the entire six days convincingly. Since then, many Japanese riders race in the SSDT to this day.

Yasuo Manzawa and Shozo Narita competing in the SSDT on their Honda TL125s led to the inauguration of Japan’s largest touring trial, the IDEMITSU Ihatove Trial in Iwate, which has been running every year for over four decades. Only COVID-19 was reason enough to cancel the event - the 44th running - for the very first time.

From their experience and excitement from racing in the SSDT, Manzawa and Narita, who were Honda motorcycle recreational riding instructors, aimed to create a Japanese version of SSDT. Through their travels all over Japan as Honda instructors, they were struck by the vast and beautiful natural environment in Iwate, and the friendly local people who warmly accepted the riders. In 1976, the first trials boom was subsiding and was seemly hard to maintain, partly due to its initial popularity leading to the notion that trials riding was difficult. This drove Manzawa and Narita to stage the inaugural Ihatove Two-Day Trial. The long distance trial traversing Iwate, from its mountains to the sea covers vast distances of challenging terrain, became hugely popular due to the feel of adventure the riders experience. Beginners’ classes were set up, and in 1996 on the event’s 20th anniversary, a record 833 riders had signed up to race. This popularity spread, and combined with initiatives to revitalize local areas, led to touring trial events being held all over the nation, and a “Touring Trial” boom.

In 1981, Honda released the Honda Ihatov TL125S trekking bike, an evolution of the BIALS TL 125.

2. The best-selling production model: Honda TLR200

Due to the popularity of the Ihatov TL125S, Honda release the new TL125 and TLR200 (4-stroke air-cooled / twin shocks) in 1983. The tri-colored TLR200, with its outstanding looks, became a best-seller. As the TLR200 went on sale, Kiyoteru Hattori, racing for Honda in the World Championship at the time, rode the all-new bike in the 1983 SSDT, and won the 151cc - 200cc class.

1983 was also the year in which Honda invited the previous season’s world champion, Belgian RTL360 rider Eddy Lejeune (see Chapter 3 for details) to Japan. He visited the Ikoma Bials Park in Ikoma, Nara, to show his skills, shocking Japanese riders with his amazing techniques. This would later be known as the “Lejeune shock.”

In January 1983, Honda held Japan’s first International Stadium Trial, staged at Tama Tech, near Tokyo. This was also popular, leading to the event being held the following year at the Suzuka Circuit in Mie. In 1985, the International Super Stadium Trial was held indoors at the Yoyogi National Gymnasium No.1 Gymnasium in Tokyo, and was broadcast on Fuji Television’s International Sports Fair program. All Japan Stadium Trials competition kicked off in 1991 on a nationwide scale.

In 1983, Honda brought attention to the world of trials through Lejeune, and gave rise to attractive events allowing people all over the country to watch trials. And, by releasing bikes that many would love (the TLR200 was street-legal, making it popular beyond trial riders), Honda brought on the second trials boom.

Chapter 2 The Numerous Glories that Honda Production Racers Brought

Chapter 1 shows how the street-legal production Honda BIALS TL125 and TLR200 brought the joy of trial riding to the wider society, and increased the awareness of trials. Chapter 2 focuses on Honda’s production trial racers, and the numerous glories they made real.

1. The sensational Honda TL200R

In 1978, the Racing Service Center (RSC: predecessor to Honda Racing Corporation established in 1982) released the TL200R, a vastly improved race-spec production racer from its origins, the 1973 BIALS TL125 production bike’s engine. Compared to the 1975 BIALS TL250 it was lighter, and its 200cc displacement was easy to handle for many Japanese riders. One of the benefits of production racers was the ability to increase engine size as the rider’s skills increased.

The TL200R later evolved into the TL200RII (1979), RS200T (1980), RS220T, and RS250T (1983). Of these bikes, all but the RS250T were 4-stroke, twin shock absorber machines.

In the All Japan Trial Championship that started in 1973, Hiroshi Kondo became Honda’s first champion by winning the 1977 championship. He went on to win the two years that followed, becoming Honda’s first rider to win three years in a row. In 1980 Taneyasu Maruyama won the championship, giving Honda four consecutive titles for the first time.

In 1982, Honda signed on Masaya Yamamoto, a 23-year-old rider then called “the kid.” Yamamoto won the championship from 1982 to 1986, singlehandedly giving Honda five consecutive titles.

2. The last 4-stroke of the ‘80s: Honda RTL250S

Honda’s 1985 RTL250S retained the 4-stroke engine, but the rear suspension evolved to Pro-Link. 2-stroke engines were mainstream, but Masaya Yamamoto had proven the superiority of the 4-stroke by winning the Japanese championship five years straight. With its glorious achievements, the last 4-stroke of the 1980s and the last racer available for street riders, the RTL250S, was no longer available.

Hiroshi Kondo and Masaya Yamamoto challenged the world. In 1977, Kondo made wildcard appearances in the Trial World Championship on his Honda RTL205 factory bike, but the results were less than expected. The RTL305 would evolve into the RTL360, but during this time, riders such as Nick Jefferies, Brian Higgins and Rob Shepherd raced RTLs on the world stage.

In 1980, Kiyoteru Hattori became the first Japanese rider to compete full time in the world championship. On his Seely-Honda TL200E/250, Hattori finished 9th in the final round in the Czech GP, and became the first Japanese rider to win championship points (which were awarded to the top 10 at the time), and got his name on the championship ranking, in 28th spot. He continued to compete in the championship in 1981 and 1982 riding the Honda RTL360, without much success. In 1983, however, Hattori rode his Honda TLR200/250 to 10th in Round 4 in Ireland, raking 24th overall. He also rode a Seely-Honda TL200E/250 in the 1980 SSDT and finished 16th, a Japanese rider record which still stands to this day.

Masaya Yamamoto made wildcard appearances near the end of the 1984 Trial World Championship, riding a prerelease RTL250S. It was a time of transition: many bikes were on twin shock absorbers, but many were transitioning to monoshocks. Yamamoto’s skills, combined with the RTL250S using Honda’s new ProLink suspension, debuted to sixth place, sending shockwaves throughout the racing world.

He raced in two rounds this year, finishing the season 21st overall. One year later in 1985, Yamamoto raced his RTL250S in five rounds, and was 25th overall. The same year, Hironobu Yamamoto also competed in the world championship on an RTL250S, and despite not scoring any championship points, showed how enthusiastic the top Japanese riders had become about challenging the world. In 1987, Ichiro Kurokawa went full time on a RTL250S in the world championship, and raced two rounds the following season on the same bike. His results were not stellar, but his son, Kenichi who had accompanied him, became world champion in the mountain bike trials, and would later on graduate to becoming an accomplished trial rider.

At a time when a Japanese rider could only dream of becoming world champion, Honda helped build a path to challenge the world. And, this first era of Honda’s trials racing would set the stage for its next era with Takahisa Fujinami.

Chapter 3 The Thoroughbred Factory Bike - Honda RTL360 - Makes History

Chapter 1 focused on Honda’s production bikes, while Chapter 2 moved on to production racers. Now, we see how Honda’s factory bike, the RTL360, made history.

1. It began with the Honda RTL305

The RTL360 began as the RTL305 (codename: A2E). If Honda, which had released the BIALS TL125 in 1973 and BIALS TL250 in 1975, was going to take the next step, it would go all the way to the top of the world. The project, built up from scratch, was spearheaded by Hideo Tanaka, in charge of development at the time. The following is a summary of his thoughts.

At the time, although 2-stroke 250cc bikes were mainstream in the Trial World Championship, Honda was intent on racing 4-stroke bikes, and to be competitive, the engine had to be 305cc. This is where the project started. Tanaka, who was the engine designer and RTL engine project leader, was given his orders. His boss had said “we want a high ground clearance and low riding position. To do that, the lower the engine height the better. That may increase the length, but it’s okay, so keep the height down.” Tanaka then began his work on the perfect trial engine.

The TL250’s engine was based on the SL250 off-road model, and was too big. The team would not refine this engine, but would design a trial engine from scratch. They had worked out the performance layout: 305cc would produce the same torque at relatively low speeds as a 2-stroke 250cc engine. By setting conditions such as how much torque is wanted at what revs, or aiming for so much maximum output without raising engine speed too much, it was possible to roughly calculate the bore and stroke, and valve diameter. Tanaka used this data to draw up the diagrams. When the first A2E’s engine came to life, Tanaka was overwhelmed with joy. The bike was big, with a long wheelbase, a high center of gravity, and a bit heavy, but it was well balanced and a solid first attempt.

To reduce weight by minimizing the number of bolts, the RTL305’s engine was designed with an integrated upper crankcase / cylinder unit. There were no sleeves within the cylinder, but was instead plated with hard chrome. Durability was not a consideration, as the cylinder and crankcase were designed to be replaced periodically on a short cycle, making the RTL305 a true factory bike.

In 1976, Tanaka took the RTL305 to the SSDT for the first time. Tanaka acted as advisor, supporting the team with Sammy Miller as director, and British riders Nick Jefferies and Brian Biggins as riders. Jefferies finished 9th and Biggins 12th, a major accomplishment. Tanaka then pondered how to approach the two following years. There were many technical trends at the time, such as 280cc and 350cc 2-stroke engines gaining popularity, as low-speed torque and quick response was needed to overcome high steps. Tanaka determined that 305cc was not big enough: they would design a 360cc engine.

2. RTL360 realizes Honda’s ambitions

Honda entrusted the RTL360 factory bike in the hands of Eddy Lejeune, a 21-year-old (in 1982) Belgian rider well regarded as a genius, who became world champion that same year, and the two years that followed. In 1982 he won 8 of the 12 rounds, as he did in 1983, and in 1984, was victorious in 6 of the 12 rounds. He had won 22 rounds in three years, giving Honda the manufacturers’ title for these years as well.

1983 was also the year that Honda invited to Japan Belgian Eddy Lejeune, who won the world championship on a RTL360 (see Chapter 3), where he demonstrated his legendary skills, shocking Japanese riders, later to be known as the “Lejeune shock.”

In 1982, the RTL360’s body color was red, with the engine’s silver left as is. Since 1983, as if to complement the TLR200 production model released that year, the RTL360 was wrapped in a tricolor scheme, with its engine painted black. The silencer was changed to stainless steel, and the model was renamed to RS360T. The air-cooled 4-stroke, OHC single-cylinder, 2-valve 360cc engine was mounted on a steel pipe diamond frame. Its maximum output was over 20 horsepower / 6,000 rpm, and its maximum torque was 3.01 kg-m / 4,000 rpm. The transmission was 5-speed. Its dry weight was 88 kg. And a norm for the time, it had drum brakes front and rear.

Although the RTL360 was renamed the RS360T in 1983, Eddy Lejeune raced in the inaugural GPA’83 International Stadium Trial at Tama Tech on January 23 that year on a 1982-model RTL360.

The RTL360 and RS360T were equipped with twin shock absorbers with two cushions on the rear, but in 1985, after winning three years straight, evolved into the monoshock ProLink suspension RS360T. HRC developed the next generation purpose-designed engine and ProLink for the new RS360T, which debuted in the world championship season-opener in Spain. This all-new machine, however, would not be racing for long.

Around the same time, in Round 7 of the All Japan Championship in Hokkaido, Honda debuted a lighter and more compact factory bike, the RTL250SW (ProLink). As mentioned in Chapter 2, Masaya Yamamoto had ridden the RTL250SW (prototype of the RTL250S street racer) in wildcard appearances in the closing stages of the 1984 Trial World Championship, and stunned the world by taking sixth place in his debut race. The RTL250SW was a second-generation factory bike which was to be retailed, and its displacement was later raised to around 290cc. In 1986, as British tobacco maker Rothmans became a sponsor, Rothmans-colored RTL250SW bikes ridden by Eddy Lejeune and Steve Sanders attempted to win back the championship crown. Rothmans livery found its way to production RTL250S and TL125 Rothmans models, proving very popular. The partnership with Rothmans also served to raise the awareness of trials competition. Honda’s partnership with Lejeune in the world championship continued until 1987.

Returning to the RTL360, it was too complex to build, and was not suited for mass production. It became the coveted factory bike that everyone wanted, but no-one could have.

matching the record Spanish manufacturer Bultaco set between 1976 to 1978. However, every bike that won the Trial World Championship since its start in 1975, were 2-strokes. The RTL360 (RS360T) became the first 4-stroke bike to win the title, validating Honda’s insistence on the engine, and displaying its technical skills. Honda had made history with a 4-stroke engine in a 2-stroke world.Honda won the world championship three years straight with the RTL360 (RS360T),

At the beginning of this chapter are Tanaka’s thoughts:
“If Honda, which had released the BIALS TL125 in 1973 and BIALS TL250 in 1975, was going to take the next step, it would go all the way to the top of the world.”

Looking back, the TL125 was designed for the trials novice, and the TL250 did not perform well as a racing bike. To aim for the world championship crown from there? It was not just a big step, but very, very ambitious. However, the company had aimed for the top of the world before: Only five years after its incorporation, company founder Soichiro Honda’s “Isle of Man TT Declaration” in 1954 was a challenge to become world champion, and within a decade, became a reality. Honda’s challenging spirit may have seemed outlandish, but the company’s traditional strengths were honed by its engineering spirit and setting the highest goals.

In its first era of trials competition Honda achieved its 4-stroke dreams. In its second era, Honda pursues the 2-stroke engine.

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