Nobuatsu Aoki On Retirement, Recovering From Cancer, Developing Suzuki's MotoGP Bike, And Teammate Jeremy McWilliams

Nobuatsu Aoki finished his road racing career as a rider at the 2022 Suzuka 8 Hours Race at the age of fifty. As the eldest of well-known Aoki three brothers, Nobu had already shown his potential in the All Japan Road Race Championship when he was a teenager back in the early 1990s. Soon after, he moved up to the 250cc grand prix class, and took an impressive victory in Malaysia in 1993. Then in 1997, he stepped up to the 500cc class to ride for Honda NSR500. He also experienced the dawn of the 4-stroke MotoGP era in Proton KR team before becoming a test rider for Suzuki.

Backed by rich experience, knowledge, and skill, his words are always full of deep insight. And his sense of humor adds a unique flavor to them. We spoke with Nobu for an hour-long interview at Suzuka Circuit on Thursday evening, the day before his last race weekend started.

Q: First of all, could you tell us a little bit about the reason why you have decided to retire from racing?

NA: The reason? Nothing but my age! Unfortunately, when you get old, your body doesn’t respond as it used to. Although I have always been training very hard, in my late 30s, I felt something changed in my body. Then, when you turned forty, that strange feeling started growing even more. For sure, I still think I am still young like a teenager. However, if you train hard like a teenager and ignore your age, you can very easily end up with an injury in training. You run very hard, you lift a heavy barbell like you used to do, then you pull your muscles or injure your joint!

So, it becomes harder and harder to maintain your performance. And you reach your late forties, now the old injuries start hurting again. It takes time just for those old injuries to heal. Therefore, if you want to start training, you have to train yourself to make a base physical condition before starting the normal training. Then, when you finished training yourself to go training, now you can finally start your original training!!

So, in 2019 I was thinking I would quit in 2020. When I raced the 8 Hours in 2019, deep down I had decided that next year would be my last one. But due to the pandemic, the 2020 race was canceled, so was the 2021. And during that period, I was diagnosed with throat cancer, and had a fracture in my foot. Although I have made a comeback, my body is very honest, and I do not have the same power as before anymore. I really feel that. I think I still have some good durability as a rider, but at the same time, I know I can't improve my lap times as much as I want to.

Q: As you said, during the two years, you came back from cancer treatment and a foot fracture. Have you already decided to retire before these tough times?

NA: Even though I switched from EWC to SST for the 8 Hours category, I still want to get good results. I am always looking for a good result, but I know now I don’t have an instantaneous power like I used to have, and I cannot stay in the leading group. If it is the case, I should retire. As I said, I had already decided to retire in 2020 before the 2019 8 Hours, so it was originally a two-year project.

Q: Did you decide without hesitation, or did it take some time?

NA: To be honest, I could have retired at any time after turning 40. But there was no specific reason to do it. In fact, I felt I could keep racing at a decent level. If I don’t try to pursue results and do it just to enjoy the race, I am confident I can keep racing for ten more years. But I am not the kind of guy to think 'taking part is more important than winning'. As long as you are competing, you have to chase the best result. I always think like that. And if you are not able to chase the best result, you have to step down from there. This is my way of thinking. Having said that, I am guessing the biggest reason for most athletes’ decision for retirement is, it is simply because too hard to continue.

Q: Too hard physically or mentally?

NA: Everyone comes to the championship to be the best guy in the world, so when you know you are not competitive anymore, it would be very hard to accept. Maybe it looks like my career is way too long, I could keep doing it thanks to the people who have been around and supported me.

Q: Maybe it is too private thing and not an appropriate question, but, does the fact that you overcame and returned from cancer have anything to do with your decision to retire?

NA: To be honest, I don't feel like I've conquered cancer. Now I think of it as catching a really bad flu or something. But when I hear that someone had cancer, it is hard…

I've been in hospital many times in my career and am quite used to being in the orthopedics ward, which has a very light atmosphere because they know it will curable. On the other hand, the atmosphere in a cancer ward is very heavy. Some percent of the patients there might not be able to go out from there alive. In such a hard situation, I was always looking forward, both in a good way and bad way. Thanks to the doctors, now I am able to ride my bike and participate in races again, and for that, I am truly grateful to them.

Q: Your survival from cancer and returning to the races definitely encourages people who have experienced cancer and who are fighting the disease right now.

NA: It depends on personalities, but some people may be very scared and depressed when they know they have cancer. I am not sure if my racing activities encourages them, but maybe just after my return, I had tried very hard to show people that I was OK and doing well now.

Q: Looking back from now, do you think your view of life has changed after that experience?

NA: (Long pause and silence.) …….My view of life……well,......, I always have been doing what I want to do in my life. But you may suffer a serious disease at any time in your life, so that you shouldn’t hesitate to do what you want to do. I strongly believe this.

When I was in the hospital for two and a half months, I saw people getting weaker day by day, and I myself lost 10 kg.

Q: Losing 10kg from an athlete's body that has reduced body fat to the limit, it means.......

NA: Only muscles. What I lost 10kg were all muscles. So, I had to start over again for everything. Although now I’m feeling much better, I had some side effects from the cancer drugs and radiation therapies. For example, I lost my sense of taste. It's slowly getting back, but I still have no sweet taste. Even when I lick sugar, I feel like, "Hmm, sand? No matter how much sugar I put in my coffee, I don't taste any sweetness at all. And more than anything, I don't have saliva. With the radiation treatment, they burnt my throat, so the tissues around here are damaged. When I do 5 laps, my mouth is completely dry. So, hydration really matters to me.

Q: Riding the 8 Hours race with the such physical condition must be very hard…

NA: Yup, but as long as my mouth is hydrated, it should be no problem.

Q: You just said you could go on racing thanks to the people who have been around and supported you. I just remember that a long time ago, you said you were the most untalented among your three brothers. What do you think about that now?

NA: I still think that's true. It is obvious when you see the results. Haruchika has won two world titles. Takuma has won two All-Japan Road Race Championship titles and took the podium immediately he came to the 500 GP world championship. Considering this, I felt that I was the least talented of the three. I also thought that I should not lose to them because I am the oldest. To be honest, I always felt that pressure from these two guys.

Q: Maybe you are the typical 'oldest brother' type.

NA: Exactly. Back then, I didn't really understand what the oldest brother type looked like, but now that I am 50 years old, and when I look around at society and take a look at the oldest brother here and there, I found out that I am really the typical oldest brother type! We don't do anything flashy or anything big. Instead, we just do things patiently and never give up doing them.

Q: Looking back on your long career, how satisfied are you with your achievements? Is there anything you feel you have left undone?

NA: Let’s see…. Well, if I wanted more, I would've liked to be on the podium a few more times, and I would’ve liked to win the championship if I could.

But when I was competing in the grand prix, I was always good friends with Tetsuya (Harada), and although I didn't think so at the time, now I really understand that he had a very strong determination. Of course, I always tried to go faster and go higher places. But Tetsuya was more hungry than me to win races and championships.

But if I had the same hunger as him, would I have been able to win, too? No, I don't think so. Tetsuya was a guy who did everything that he could and should have to do, and he meticulously prepared everything to get what he had dreamt of, and finally he made it. In that sense, maybe I didn’t do things enough in the same way he did. Even if I copied what he did, I don’t think I could get the same results as Tetsuya.

On the other hand, I could spend a lot of days in the 500cc and MotoGP. I am proud of what I did and I can say I gave my 100%.

NA: If you are allowed to go back in the past and redo only one day, which day would you choose?

NA: Hmm, I really wanted to be on the podium with Suzuki. That's the only thing I regret.

Q: So, what was the most memorable race for you? Memorable in a good way and memorable in a bad way?

NA: Let me see… Well, I would choose the 500cc race in Imola (1997 City of Imola GP) when I stood on the podium with Takuma. Definitely, it was the highlight for us. The worst one was ......, there are too many to count!! One of the most recent fiasco was that I crashed in the opening laps when we entered as "Legend Team" with Kevin (Schwantz) and Tsujimoto-san (Satoshi Tsujimoto: former Suzuki factory rider).

Q: I remember it very well. the rainy 8 Hours (2014).

NA: Exactly.

Q: The race you crashed at the chicane and broke your left hand, and needed to have surgery.

NA: That’s right! To be honest, even with that team, I was trying to win the race, But if you think about it calmly, all I had to do was finish the race.

Q: But as a rider, you always have to aim for victory. It is riders’ natural instinct, isn’t it?

NA: Maybe you’re right. But as a rider, you also have to understand the situation and accept it. I still can't.

Q: Looking back on your long racing career, you started out in the All Japan Road Race Championship from the Cup Noodle Honda 250cc team. Then you entered the 250 GPs and won immediately in Malaysia. In 1997, you moved up to the 500cc class from Honda, then went to Suzuki before moving to Proton KR. After that, you became a Suzuki test rider in 2005. From these rich experiences, where do you define your identity?

NA: When it comes to my MotoGP-related career, I have three things that I was involved in the development project from scratch. Kenny's 5-cylinder (4stroke 990cc Proton KR), Bridgestone MotoGP tires, and Suzuki's GSX-RR. I'm really proud of these three projects. During the project periods to develop them from scratch, I got things down to the level that 'no other riders but me can do such a deep analysis'. And thanks to those experiences, I came to understand both the good and the bad points of motorcycles very clearly and easily!

Q: Which development is the most memorable?

NA: Well…(long pause)…I think it was Suzuki. The three to four years during the transitional period from the final days of GSV-R to the beginning of GSX-RR was very intense for me. It was the pioneering days of the current ECU, and the frame was changing very rapidly. I was working on it right at the cutting edge. I'm sure it was tough work for Suzuki engineers, but I really enjoyed the process of things getting better every single week.

Q: How were your Proton days? In those days, you spent more time staying in your pit garage than riding on the track. It looked very hard from the outside of the box. But in hindsight, I think it was a very fulfilling time, too.

NA: For example, Japanese manufacturers take at least six months or a year to check durability and drivability very carefully during the process of the development.

But in the case of Proton KR, they would just say, "It's done! OK, the engine runs!" Then they brought it to a small airport and did about 10 short laps, and say, "Okay, Now we can bring it to Le Mans!" So, I thought “oh, really? ...Do you think we're finished?" Everything is like that. There’s no way we can complete the race weekend with that bike!

What I still remember very well is our engine. It had twin injectors, as most bikes have now. There was one injector on the bottom for lower speed and another one for high speed on the top. When you look at the data, there is a moment when the bottom one is injecting, then it switches to the injector from the top. But when I accelerate the bike, the engine stumbles very momentarily. So I said to the engineer, "It stumbles. ......" But they said, "No, that's not true." The engineer said, "There is no gap in the injection timing, and switching from bottom to the top is very smooth and precise." But, when I rode the bike, it stumbled again when I opened the throttle.

The bottom line is very simple. Theoretically, the bottom injector is spraying and it switches over to the top injector. But the top and bottom injector had, say, a few centimeters of distance between them, and that distance created a very tiny lag (vacuum) of the non-injected area in the combustion chamber. That was the reason why the engine stumbled.

So, we tried to overlap the time just a little bit between when the bottom injector stops and the top injector starts spraying. Then, two injectors worked together smoothly and the engine stumble disappeared. Theoretically, the two injectors switched over very smoothly. But physically, there was a very small point where gasoline was not filled in the combustion chamber.

This was just an example of the way we eradicated small discrepancies one by one. And through this experience, we riders finally learn “wow, there are two injectors in the engine!"

We usually describe the "symptoms" by riders' feelings, but the speed of the development depends on how we communicate with the engineers. It can be longer or shorter depending on how we speak to them.

These experiences in Kenny’s team helped me a lot to work as a test rider in Suzuki. When you explain things with engineer-friendly words, you can drastically shorten the development period. When I began to understand this secret, I really felt the development job was very enjoyable.

Q: It’s all about how you eliminate "lost-in-translation" between riders and engineers?

NA: That's right. At Suzuki, we always tested at Ryuyo (Suzuki’s test track) every week. When you commented in the language of riders, it took some time for engineers to understand, and that's where the “time lag" for the development was created. Eliminating the time lag as much as possible is very important, so that after we tested on Sunday, the engineers could start development work immediately on Monday. After I kept that in my mind, communication and cooperation with the engineers went very smoothly, In fact, the development speed was greatly improved.

Q: Your teammate at Proton KR days was Jeremy McWilliams. I was just wondering how he commented and communicated with engineers?

NA: Jeremy is a 100% feeling guy. As I mentioned earlier, Proton KR first introduced their four-stroke engine at Le Mans (2003 Rd04), and until then we had been racing with the two-stroke 500cc.

Although we brought it to Le Mans and rode it in the Friday morning session, they said “we have some issues with it, so you have to ride the two stroke in the afternoon. I could only say “what?"

And the next day, they said “we fixed the issue, so you can ride it in the morning". I was like “OK…", and then in the afternoon they said “we have an issue again, so you have to go back to the two stroke once more in the afternoon". It was a confusing situation. Nevertheless, Jeremy switched between the two stroke and the four stroke without a hitch. As my teammate was just getting on and riding without flinching, I couldn’t make any excuses, so I was crying in the helmet and saying “what the heck is going on….!!"

So, Jeremy is a natural-born racing rider. In terms of the setup, I always change small things very carefully, while Jeremy’s setup way was like “Bang!..,Bang!!...,Baaang!!!" He even changed the pivot after Sunday morning warm up for the race. If you try to do the same drastic things like him, you will fail! Whenever I saw such a brave change, I always thought “wow, that’s amazing…" But as a teammate and closest rival, I couldn’t lose to him. So, the three-year experience in KR were really precious days for me, because I was really trained in my guts to “go out on the track and set a quick lap time before you can complain".

Q: Which rider influenced you most in your long racing career?

NA: So, I said Jeremy! More than anyone else!!

Q: Not the rider you admired when you were a child?

NA: When I was a kid, Tadahiko Taira was my hero, and when I saw Wayne Gardner, I thought, "Wow, he's great." But to be honest, I never thought I wanted to be like them.

Q: It’s a bit surprising that from all of your long racing career, it was Jeremy McWilliams who influenced you most.

NA: (Laughs). Also, Okada (Tadayuki) san and Tetsuya, who I was competing with in those days. At that time, they were the only guys in my view back then.

Q: Those days in the All Japan Road Race Championship, the relationship between riders was very tense. It was quite different from now.

NA: Yeah, it was. I always thought I had to beat them, I couldn’t lose to them. Years later, Tetsuya became the world champion, and Okada-san came second in the world championship behind Mick Doohan. In other words, they made history for Japanese road racing. And I followed in their tracks.

Q: Did you think you would be racing until you were 50?

NA: Never. When we were young, people would say, "he's 30 years old and still racing!" Completely different from nowadays.

Q: Current 50 years old is younger than that of thirty years ago.

NA: Definitely, training extends the active life of athletes.

Q: Modern training method is very scientific.

NA: Years ago, the only way to train was to run or lift weights, and you just did what you were told, without knowing what the right thing to do was. However, after learning and incorporating various training methods from many sports fields, I have the impression that while my physical performance has declined to some extent, the rate of decline has considerably slowed down.

Q: What do you feel about Suzuki Motor Corporation’s decision to withdraw from MotoGP and EWC? You have contributed a lot to the company as a racing rider and a test rider, so you must have thought many things…

NA: I am really, really, really disappointed. I can't help but be sarcastic and say, “OK, Suzuki’s racing activities were nothing for you, so some executive members’ preference always comes first before anything."

The way they withdrew from the championships is something like putting mud on the face and feelings of those who have supported Suzuki from the bottom of their hearts. They bought and rode Suzuki bikes simply because they love Suzuki and they love Yoshimura. Nevertheless, the company decided to quit because of financial reasons, so I can say nothing but very disappointed.

Q: The various things that Suzuki has cultivated through its racing activities over the years may not show up in financial information, but that is why they are such valuable and irreplaceable assets.

NA: It's very true. it is always difficult to see the cost-effectiveness of racing activities in the financial information. For example, if you look at the Japanese market alone, it may be true that the motorcycle market is very niche and has nothing to do with the four-wheel industry. But once you go outside from Japan, you hear people would say, "this is a brand that competes in MotoGP, isn't it?"

Then, when you quit competition, you will become just another name in the industry. You might maintain your presence for five or ten years. But from that point on, Suzuki will completely lose their identity and presence. Then, hardship will start, and it’s too late to recover. People loved and supported Suzuki because such a small budget team could beat a Goliath like Honda.

Q: Finally, what will you do after retirement?

NA: I would like as many as people to enjoy riding motorcycles. That's why I've been doing the kids' bike program for more than 10 years. I also want to extend the riding school to people our age so that they can safely enjoy supersport bikes for a long time. For sure, we will continue Side Stand Project (a non-profit organization that Aoki brothers started to help disabled people enjoy riding motorcycles) and mini-bike races. I will working on thing sto ensure that many people can enjoy motorcycles for a long time.

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I really enjoyed Nobuatsu Aoki's great perspective on a life-time of high level racing, training, and life in general. Thank you to author Akira Nishimura for conducting such an entertaining and informative interview.


I REALLY enjoyed that interview, many thanks to Akira Nishimura and David Emmett for bringing the thoughts of Nobuatsu Aoki to us. Very honest and unflinching interview.

I love what he's done in his career, and that he beat the "Evil C". What he did with Team Roberts for me was extra special.

Fascinating that McWilliams, Okada and Harada were riders he looked up to. Shame that Tetsuya Harada isn't a World Champion!

Edit:  Oops, sorry Tetsuya. You are a multi-time World Champion in my eyes.  Thanks rick650.

Loved that one, brilliant.  Many great memories in that lot, I recall the 'fireball brothers' as they were sometimes known.  It was a great period for Japanese riders in Grands Prix, especially in the lower classes which in those days stood as championships in their own right rather than just filters for young talent on their way to MotoGP as it is now.  I still have a set of Yuichi Ui's knee sliders which I scored at Eastern Creek back in the day.  :)

This was fantastic.  Aoki has great character.  I happen to turn 50 a couple months from now, so this was touching.  I'll approach my trackdays with Aoki in mind.  

Very much liked this interview. Nobu comes across as a real racer, and someone you’d enjoy having a beer with.  He was with KR when I began to follow motogp in 2003. I believe Jeremy McWilliams scored the last-ever 500cc 2-stroke poll, at PI, that year.

As I often do, I settled down at my desk-top computer to see what MotoMatters had to say about the world I have loved since the 1960's.  I sipped my mug of fresh coffee, and opened this interview........................Whow ...............Everything on hold for 30 minutes! ......................VERY cogent comments from a man who has dedicated his life to road racing, lived to tell of it, and speaks so intelligently about so much than just riding. ...............What a pleasure !


Thanks a ton David for these insightful interviews. The experiences and insights are just amazing - especially the description about the "stumbling" when switching over from lower to upper injectors.