As many as 49 drivers are entering the first round of Japanese F4’s 11th season at Fuji this weekend with a grid that combines Japan’s up-and-coming talents and gentleman drivers alike. Feeder Series tells you everything you need to know about the upcoming season.

By Finjo Muschlien

After Japanese F4 introduced the Toray Carbon Magic MCS4-24 car and the 180-horsepower TOM’S TMA43 engine for the 2024 season, even the usual frontrunners faced a period of major change. Toyota’s junior team TGR-DC Racing School and its drivers had the most difficulties, collecting just three wins all season. This meant that Honda juniors Yuto Nomura and Ryota Horachi featured in the title fight, and the more experienced Nomura took the crown with five consecutive wins in the final six races.

In the past 10 seasons, all drivers’ champions were Toyota or Honda juniors, and the two manufacturers – inclusive of the TGR-DC Racing School’s predecessor, TOM’S Spirit – also won all teams’ championships in the series’ history.

Following the introduction of the new car last year, teams and drivers without manufacturer support came much closer to the front. With the grid looking more balanced than it ever was, this pattern may finally end in 2025.

The calendar

As in every season of Japanese F4 so far, all rounds will support the series promoter’s flagship event, Super GT. The first round at Fuji and the fourth round at Sugo will have three races instead of just two, while one of the Suzuka rounds has been scrapped. The series had an official pre-season test at Fuji on 31 March, which offered 150 minutes of running in rainy and snowy conditions.

• Round 1: Fuji Speedway (1–4 May) 
• Round 2: Fuji Speedway (31 July–3 August)
• Round 3: Suzuka Circuit (21–24 August)
• Round 4: Sportsland Sugo (18–21 September)
• Round 5: Autopolis International Racing Course (16–19 October)
• Round 6: Mobility Resort Motegi (30 October–2 November)

The format

Despite running as a support series to Super GT, which has all its practice sessions, qualifying sessions and races held on Saturday and Sunday, Japanese F4 begins its weekends on Thursdays. Practices are held on Thursdays and Fridays, and both the Champion Class and Independent Class have an individual 30-minute practice session on each day. Both days end with a collective practice session for both classes, which has a duration of 45 minutes on Thursdays and 60 minutes on Fridays.

Qualifying takes place on Saturday mornings, with both classes having separate 20-minute sessions. The fastest times of each session sets the grid for the first race, while the second-fastest times set the grid for the second race.

The first race usually takes place midday Saturday and the second race Sunday morning. Each race has a duration of 30 minutes. In 2024, the series attempted to split the second race at Sugo by class, but heavy rain meant that the Champion Class race did not go to green flag conditions. As of now, there is no information on whether the series will do split races again. 

The opening round at Fuji will feature 49 entrants, but just 45 drivers will qualify for the races. The series did not clarify whether the two slowest drivers from each class or the four slowest drivers overall drop out.

Points are awarded using the standard FIA points format, without bonus points. The series supports a separate championship for the Independent Class, for which the FIA points format is used as well. Points for the teams’ championship are awarded for every team’s best-scoring driver in a race.

Where to watch

All races are live-streamed and free to watch with Japanese commentary on the series’ official YouTube channel. Within Japan and broader Australasia, live timing is available on the Super GT race app for €6.91.

Teams and drivers

HFDP with B-Max Racing Team

Having won the teams’ championship and fielded both champion Yuto Nomura and runner-up Ryota Horachi last year, HFDP with B-Max Racing enters 2025 on the front foot. The collaboration between Honda’s junior programme – which had its own title-winning Japanese F4 team until 2023 – and B-Max began last year. This year the team continues to field two juniors from Honda’s academy, with both drivers competing in the Champion Class. 

Kotaro Shimbara (#50) will enter his third full season of Japanese F4 but his first as a Honda academy driver after winning the 2024 Honda Racing School scholarship alongside Rintaro Sato, now in French F4. Shimbara came third in the 2024 Japanese F4 drivers’ championship after taking one win and four podium finishes, racing for Kageyama Racing. With that, the 20-year-old was the highest-placed driver in the standings without academy support. Shimbara is seen as a title favourite given his strong performances last year and two previous seasons of experience. 

Syo Momose (#51) will partner Shimbara as he enters his first F4 season in 2025. The 17-year-old gained previous single-seater experience in Super FJ and the Honda Racing School in 2024. Despite only being a finalist rather than a scholarship winner, Momose has still joined Honda’s academy, an unusual occurrence. 

B-Max Racing Team

Alongside the satellite team for Honda’s junior programme members, B-Max fields five additional cars. With a few exceptions, the team mostly fielded gentlemen drivers in the past seasons and will do so again this year, with three of their five drivers competing in the Independent Class.

Team owner Ryuji Kumita, who competes under the pseudonym “Dragon” (#30), won the Independent Class title last year and returns as the title favourite in the Independent Class. The 58-year-old has also competed in every season of Super Formula Lights.

Kumita will be partnered by Nobuhiro Imada (#44). The 60-year-old was the runner-up in Japanese F4’s Independent Class last year, finishing just 2.5 points behind Kumita. Imada is also competing in Ferrari Challenge Japan and Super Formula Lights this year, though he missed the opening round of the latter because of a finger injury.

The team’s third Independent Class competitor is Kazutaka Miura (#88), though because he will miss the season opener, his Japanese F4 debut will have to wait. Miura, like Imada, competes in Ferrari Challenge Japan. The 41-year-old came 14th in the Independent Class in the spring test. 

In the Champion Class, Ayato Iwasaki (#52) will make his full-season debut in Japanese F4 having previously competed in six races in 2022 with Buzz Racing. The 20-year-old is more known outside of Japan for doing a partial GB3 campaign with Elite Motorsport in 2023, finishing 24th overall with a best result of second. Iwasaki came 26th of all Champion Class drivers in the spring test.

Tosei Moriyama (#43) was a last-minute addition to the team and was originally scheduled to spend the 2025 season on the sidelines. The 22-year-old came fifth in Japanese F4 last year with Helm Motorsports, bagging a win and three further podium finishes, and represented Japan in the FIA Motorsport Games F4 Cup. He made his Super Formula Lights debut during the first round of this year as he stood in for Imada. His performances impressed Imada, who is the team principal of B-Max satellite JMS Racing Team, so much that he decided to field an additional car in Japanese F4 for Moriyama.

TGR-DC Racing School

After a difficult year in 2024 in which Yuki Sano and TGR collected just three wins all season and pre-season title favourite Kazuhisa Urabe failed to take even a podium, the team are in need of an improvement in 2025. This year, TGR-DC expand their fleet from four to six cars, four for rookies. All drivers will compete in the Champion Class.

Kiyoshi Umegaki (#28) is one of two returning drivers this year. The 17-year-old finished seventh overall with a best result of fourth at Suzuka last year and was the highest-placed rookie. For this year, Umegaki will do a dual campaign, racing in FRegional Japan with Toyota-affiliated team TOM’S as well.

Tokiya Suzuki (#29) is TGR’s other returning driver this year and is likewise set for a dual single-seater campaign. Last year, the 18-year-old finished 10th overall with a best result of fifth, which he secured at Fuji and Sugo. Suzuki will partner Umegaki at TOM’S in FRJ this year and topped the series’ joint test on April 2. Additionally, Suzuki debuts in endurance racing this year, driving a Toyota GR Yaris in Super Taikyu with KTMS in the ST-2 class.

Don’t get confused with the names at TGR, as F4 debutant Megumu Suzuki (#35) will also race for the same team in 2025. The 16-year-old, a new member of the Toyota Racing School, came 12th in the series’ annual spring test at Fuji on 31 March.

Takahiro Kikuchi (#36) will step up from karting as he transitions to single-seaters in 2025. The 16-year-old raced for Drago Corse in the GPR karting series’ OK class last year. Kikuchi made his single-seater debut in the F110 Cup, taking a best result of 12th in the first race of the opening round, and he also finished 10th in the Japanese F4 spring test as TGR-DC’s highest-ranked rookie.

Masana Muto (#37) is the youngest driver to compete in Japanese F4 this year, having turned 16 on the Monday of the first race week. Muto will debut in F4 this year, having previously competed in the GPR karting series’ OK class with TGR–supported team Formula Blue and finishing third overall. 

Yuzuki Miura (#38) gained previous single-seater experience from competing in Super FJ and various other events in Japan and South Korea. The 18-year-old, who will also debut in Japanese F4, came 11th in the spring test.

Kageyama Racing

Kageyama Racing fielded just one car in Japanese F4 in 2024 with Kotaro Shimbara as their driver, but with only the best points finisher from each team contributing to the standings, the team finished third overall and as the best-placed of all teams without manufacturer support. For 2025, the team expand their line-up to three cars, all for drivers competing in the Champion Class.

Ryo Shirasaki (#16) switches to Kageyama after having finished 13th overall with a best result of fifth at Motegi while racing for Bionic Jack Racing last year. The 26-year-old won Super FJ’s Suzuka and Okayama series in 2023. This year, Shirasaki also races in MEC120 with v.Granz. 

Itsuki Sato (#17) likewise enters his second season of Japanese F4 in 2025. He has made the switch from Drago Corse, with whom he finished 12th overall in the 2024 season. Sato, 22, also races in Porsche Carrera Cup Japan with the Porsche Japan Junior Programme for 2025.

Ryusho Nakazato will be Kageyama’s sole debutant in the 2025 season, though he will not take part in the first round at Fuji after having also missed the spring test in March. The 17-year-old karting graduate competed in the GPR karting series’ OK class last year, racing for Parolin Japan and finishing 32nd overall. Alongside his planned Japanese F4 campaign, Nakazato will compete in shifter karting in the OTK Kart Japan championship and the GPR Karting Series.

Drago Corse

Drago Corse were one of the positive surprises of the 2024 Japanese F4 season. Fielding Hironobu Shimizu and Itsuki Sato, the team jumped from not scoring any points in the 2023 season to finishing fourth in the teams’ championship with 115 points in 2024, helped greatly by the pair’s consistency. For 2025, the team bid farewell to both drivers and instead field two rookies, who both compete in the Champion Class.

Yuta Suzuki (#33) steps up from the GPR karting series’ shifter class, having finished second behind former Super Formula driver Nobuharu Matsushita. Suzuki, 16, made his F4 debut in the F4 Middle East Championship this winter, racing for Pinnacle Motorsport and PHM Racing and finishing 22nd overall with a best result of 11th. Alongside Japanese F4, Suzuki competes in the F110 Cup, in which he took a best result of seventh in the first race of the opening round. 

Fuki Tanaka (#34) will likewise debut in F4 this year as he steps up from karting. The 19-year-old was one of four finalists in the 2024 Honda Racing School. He finished 18th overall in the spring test in March.

Helm Motorsports

Helm Motorsports had a highly successful 2024 season in which Tosei Moriyama gave the team its first win in the series since Reiji Hiraki’s victory at Fuji in 2020. In 2025, the team will field two rookies in the Champion Class and two Independent Class drivers.

Haruto Nakai (#62) steps up from the GPR karting series’ OK class in which he competed for Team Wolf, finishing 11th overall. The 16-year-old made his single-seater debut in the opening round of the F110 Cup, in which he took a best result of second in the second race. Nakai finished 24th overall in Japanese F4’s spring test. 

Nakai will be partnered by fellow debutant Fuji Kishi (#63), who likewise steps up from the GPR karting series’ OK class. He finished 21st overall while driving for Momox Kart Racing, but he fared better in the Japanese F4 spring test, placing in ninth.

In the Independent Class, the team will run American-Japanese driver William Sakai (#61), who returns to Helm Motorsports after having competed in four rounds last season with them. The 40-year-old did not take part in the spring test.

Sakai will be partnered by Go Shimizu (#64), who will make his F4 debut this year. From 2003 to 2005, the 50-year-old competed in the GT300 class of Super GT and its predecessor, the All-Japan Grand Touring Car Championship. Shimizu finished 11th in the Independent Class in the spring test.

Ponos Racing

Having joined Japanese F4 in 2023, Ponos Racing had a successful first season with debutant Kento Omiya, who finished 11th overall. Omiya improved to ninth overall in 2024, this time with two podium finishes, as rookie teammate Rintaro Sato took eighth. With Sato going to French F4 after winning the Honda Racing School scholarship and Omiya stepping up to FR Japan, the team have an all-new line-up for 2025, including an unexpected series returnee. 

Ryota Horachi (#45) took a win and seven further podium finishes and came runner-up in Japanese F4 last year while racing for B-Max Racing’s HFDP satellite. That should have warranted a step up to Super Formula Lights, but against all expectations, the 18-year-old will stay in Japanese F4 for a third full season as he makes another title bid. Horachi is no longer a Honda junior, but he has joined Hironobu Yasuda’s Hirotex Management, which supports several Honda juniors.

Ryuma Sako (#54) will partner Horachi as he makes his debut in Japanese F4. The 17-year-old, who won the Suzuka and Okayama Super FJ series last year, finished 20th in the spring test. He previously competed in MEC120 and the Sepang 1000 km endurance race. Sako will be managed by Ramblas, who also supported Théo Pourchaire and Marino Sato. 

Bionic Jack Racing

Bionic Jack Racing retain their two-car line-up for the 2025 and continue to field a driver in both classes.

In the Champion Class, Ai Miura (#97) will take over Shirasaki’s seat as she makes her debut in Japanese F4. The 35-year-old won the Kyojo Cup title in 2020 and came runner-up in the national class of Japanese F3 in 2015 and overall in FR Japan in 2021. Miura did not take part in the spring test. 

Bionic Jack retains its 2024 driver in the Independent Class, as Ikari Goto, racing under the pseudonym “Ikari” (#98), enters his fourth full season of Japanese F4 with the team. The 63-year-old came 10th in the Independent Class last year, scoring a best result of third on two occasions. Alongside Japanese F4, he competes in Porsche Carrera Cup Japan with BJRacing Porsche.

OTG Motor Sports

OTG Motor Sports will expand their line-up from one to two cars in the 2025 season, both for Champion Class drivers. The team previously fielded winners of the FIA F4 Challenge Driver scholarship, a list that includes Togo Suganami, Reimei Ito and Yuto Nozawa.

As part of that arrangement, the team fielded Kenta Kumagai (#60), who won the scholarship for the 2024 season. While most drivers leave after one year, Kumagai got a second year in the championship because of challenging circumstances such as bad weather that affected multiple races last season. The 19-year-old finished 14th overall last year, with a best result of fifth at the opening round at Fuji. Kumagai came 15th in the spring test.

Partnering Kumagai will be Miki Onaga (#80), who makes her debut in the series. The 27-year-old, who finished 14th in the spring test, is the 2022 Kyojo Cup champion and the 2023 All-Japan EV karting championship winner. Alongside Japanese F4, Onaga competes in the Kyojo Cup with KCMG and the TGR 86/BRZ Cup with OTG.

Rn-sports

Rn-sports fielded two drivers in the Independent Class in 2024. The team will expand their line up to three cars in 2025, with all three drivers competing in the Independent Class. 

Isao Nakashima (#10) remains on Rn’s line-up for his third full season of Japanese F4 with the team this year. The 59-year-old came seventh in the Independent Class last year, taking a best result of third at Suzuka. 

Team director Masayuki Ueda (#11) will enter his fourth season of Japanese F4 this year. The 64-year-old came sixth in the Independent Class last year with a best result of second at the third Moteg race. Ueda was previously active in FR Japan and Super GT’s GT300 class, and he also took part in the Fuji round of the World Endurance Championship in 2013, driving a Nissan-powered Zytek Z11SN LMP2 car alongside Katsuyuki Hiranaga and mid-2000s F1 test driver Björn Wirdheim.

Rn’s sole addition for 2025 will be Kentaro Kojima (#74), who will make his debut in the series. The 51-year-old came 16th in the Independent Class in the spring test.

Skill Speed

Having fielded just one car with Daiki Matsuda in five of the seven rounds last year, Skill Speed will continue to field a single car in the championship.

Yoshimasa Kano (#77) will make his Japanese F4 debut for the team in the Champion Class. He previously competed in the first round of the F110 Cup, in which he took a win for Akiland Racing. 

Dr. Dry Racing Team

Dr. Dry will have an unchanged driver line-up in the 2025 season. 

Racing in the Champion Class, 24-year-old Rio Shimono (#87) came 18th in the championship last year. She took her best-ever finish in the series of ninth at the second Motegi race. Alongside Japanese F4, Shimono competes in the Kyojo Cup and F110 Cup for Dr. Dry.

Hachiro Osaka (#86) in the Independent Class enters his seventh season of Japanese F4 this year. He finished 13th in class last year with a best result of fourth at the opening round at Fuji. The 64-year-old also competes in MEC120 for Dr. Dry.

Buzz Racing

Buzz Racing will expand their line up from one to two entries in 2025.

Buzz Group Inc chief executive Ken Watanabe, who races under the pseudonym “Ken Alex” (#6), returns to the championship, having made his debut in the series last year. He raced in the Independent Class, coming ninth with four podium finishes. Throughout the year, the 42-year-old received coaching from then–Super Formula driver Iori Kimura. 

Hitoshi Sakai (#7) will partner Watanabe at Buzz Racing as he makes his debut in the championship. The 53-year-old finished 18th in the Independent Class in the spring test.

TGM Grand Prix

One of the most notable additions to the Japanese F4 grid in 2025 is Super Formula team TGM Grand Prix, who field two cars in the Champion Class. The outfit made their debut in the series in the final round of last year’s championship.

Their sole driver in that event was Shota Sakai (#53), who will enter his first full Japanese F4 season with the team in 2025 as he steps up from Super FJ. The 17-year-old topped the spring test by 0.471s over Shimbara in second. He will also compete in Super FJ, the F110 Cup and Formula Beat with First Garage.

Leon Ochiai (#8) will partner Sakai at TGM, as he likewise makes his debut in Japanese F4 after stepping up from Super FJ. The 16-year-old came 13th in the spring test, and alongside Japanese F4, he is competing in the F110 Cup with First Garage. 

Zap Speed

Zap Speed will have an unchanged one-car line-up in the 2025 season, fielding Masaki Murata (#14) in the Champion Class. Murata, 21, came 22nd overall in the championship last year, with a best finish of 11th at the second Motegi race. He placed fifth in the spring test.

Akiland Racing

Akiland Racing were active in Japanese F4 since the end of 2019 and were known for being one of the teams fielding the most drivers. In 2023, the team fielded seven cars, but since the introduction of a new car last year, the team have seemed to settle on running three cars.

Keito Matsui (#19) will make his debut in Japanese F4 in 2025 as the team’s only Champion Class entrant. The 20-year-old gained previous single-seater experience racing for FTK in Super FJ and came eighth in Japanese F4’s spring test.

Masayoshi Oyama (#71) has been active in Japanese F4 since 2019 and joined Akiland in 2020. Since then, the 59-year-old has taken a best result of eighth in the Independent Class in 2022. Alongside F4, Oyama competed with Akiland in GT World Challenge Asia’s GT4 class in 2022 and 2023, winning the title in the first of those, and the TCR Japan series in 2020 and 2021.

Oyama will be partnered by 51-year-old Makio Saito (#96), who has been active in Japanese F4 since 2018 and a part of Akiland since 2020. In his time in F4, Saito secured a best result of second in the Independent Class in 2022, taking a win and 10 further podium finishes in the separated class. Saito also came third in the Independent Class in 2023 and 2024.

Field Motorsport

Active since Japanese F4’s launch in 2015, Field Motorsports brought several talented drivers to the grid over the years, including Miki Koyama and Shunsuke Kohno.

As in the previous two years, the team is set to field a single car for Kentaro Takahashi, who races under the pseudonym “Kentaro” (#55). Takahashi has been active in Japanese F4 since 2022, driving for Field in all three seasons he has previously run. The 42-year-old competes in the Independent Class and took his best result last year, when he came fourth in the class with two wins.

Eagle Sports

Having competed in the series since 2023, Eagle Sports will field two cars in the Independent Class.

Tadakazu Kojima (#21) has been active in Japanese F4 since the 2022 season, when he competed with Saccess Racing. The 58-year-old made the switch to Eagle Sports in 2023 and competed in the first six out of seven rounds that year, finishing 11th in the Independent Class. Kojima returned in the final round of the 2024 season after sitting out much of the year.

Shoichiro Akamatsu (#40) competed in Japanese F4 in the most recent season, finishing eighth in the Independent Class with a best result of third at Suzuka. The 53-year-old topped the spring test in the Independent Class.

DayDream Racing

Having mostly ran partial seasons before, Yuichi Sasaki (#4) returns for his 10th season in Japanese F4 in 2025, his ninth with his own team DayDream Racing. The 61-year-old came 12th in last year’s Independent Class standings with a best result of fourth in the final round at Suzuka. Sasaki finished the spring test 17th in the Independent Class.

Team 5Zigen

Entering its second season of Japanese F4 in 2025, Former Formula Nippon team Team 5Zigen will expand their line-up to two cars, one for a driver in the Champion Class.

Sena Yamamoto (#3) is set for his first full season in Japanese F4, having completed two rounds in the series in 2022. The 21-year-old most recently competed in the BMW & Mini Racing series in 2024, winning the title in the Mini Challenge class while driving for 5Zigen. He also won Super Taikyu’s ST-TCR class in 2024 for M&K Racing.

Motohiro Kotani (#5) made his F4 debut last year, finishing 14th in the Independent Class standings with a best result of third at the opening round at Fuji. The 53-year-old came eighth in the Independent Class in the spring test.

N-Speed

Yugo Tanabe, who races under the pseudonym “Yugo” (#23), has been active in Japanese F4 since the series’ launch in 2015, racing with N-Speed. The 66-year-old took a best result of eighth in the Independent Class in 2018. He also won the masters’ title in FR Japan last season after having made occasional entries in the series from 2020 to 2023. Alongside Japanese F4, “Yugo” competes in the F110 Cup, and he took a best result of 15th in the second race of the first round.

Fujita Pharmacy Racing

Fujita Pharmacy Racing will field returning Champion Class driver Shouma Arimura (#46), whom they ran in 2024. The 25-year-old came 23rd last season with a best result of 11th in the first round at Fuji. 

Ragno Motor Sport

Ragno Motor Sport will likewise debut in Japanese F4, fielding Champion Class driver Lin Chenghua (#48). The 27-year-old from China made his single-seater debut for Akiland Racing in Japanese F4 last year and went on to finish 20th in the Champion Class with a best result of 10th at Fuji. The Chinese driver previously competed in touring cars in China in 2022 and 2023. Chenghua also tested with 2025 FR Japan outfit Team LeMans during the spring.

Header photo credit: Japanese F4