Yamaha’s MotoGP plans: ‘With an inline-four you need to make aero compromises’

Obviously, Yamaha has yet to release any info about the V4, but you can be sure it will be a 90-degree V4, or perhaps an 86-degree V4, like KTM’s RC16. This was as far as KTM could go without losing the engine’s vital primary balance, while at the same time shortening the engine by few millimetres to help chassis designers package the whole machine, because V4s aren’t easy to package.

Mat Oxley: Yamaha is now working in two different directions – continuing with the inline-four, while also building a V4, so you must be thinking in two different ways.

Max Bartolini: “Yes, we have to think in two different ways. I think the engine is the least difficult part of building a V4 bike. It’s difficult, but an engine is an engine, and we will find a way to make the engine work. To build the bike around the engine is the difficult part.

“If you want to make the tyres work you need to go in the same direction [as the other manufacturers]. The V4 layout will itself bring the bike in that direction, whereas the inline-four engine needs to find its own way to go in that direction.

“We also have to consider aero. If you have a wider bike [inline-four engines make wider motorcycles because they are four cylinders wide, not two] you clearly have to develop your aero along the wheelbase of the bike [longitudinally]. If you have a narrow bike you can go sideways [laterally] with the aero. And if you need to generate downforce at high lean angles you need to make your aero on the side of the bike, not along the wheelbase, so with a wide bike [an inline-four] you need to make [aero] compromises.

There are many reasons you decided to build a V4 – one of them must be that inline-fours use U-shaped cornering lines, while V4s use V-shaped lines, which makes it very difficult for an inline-four to fight with V4s…

“As you say, ‘V’ bikes work in a different way. You also need to think that when we think about ‘V’ bikes, we think mostly about Ducati, because this is the best ‘V’ bike. And the Ducati never really carries corner speed in a natural turning way.

“I don’t know if it’s possible to make a four-inline work like that, but again I think this is mostly due to the tyres. I don’t know if the riders could go as fast as they do now if they rode in a corner-speed way. And I think if you found a way to make a four-inline bike use the tyres you’d probably end up in similar cornering style, a V shape.

“But also we need to consider that the Honda is a V4 that wasn’t built to carry corner speed, but they still struggle, so it’s not the case that making a V4 will help us to be easily competitive.

“Last season we did get a little closer to the others. Maybe at the start we were last, together with Honda, but then we got closer, until we were more or less in line with the others, apart from Ducati, who are clearly one step ahead of everybody else, so building a V4 won’t automatically make us competitive. Yamaha is clear: we need to make a faster package and if for some reason the V4 is slower than the four-inline, we will stick with the four-inline.”

Someone told me you will test the V4 for the first time at Sepang in December…

“That seems to be optimistic [laughs]. Yeah, that would be wonderful but there’s nothing certain we can say at the moment.”

In the old days, engineers talked about chassis geometry when they talked about turning, then it was chassis stiffness, now it’s all about using front downforce to help the bike turn…

“First, I think that the chassis and other old-style factors are still important in making the bike turn. When we talk about downforce aerodynamics, it’s the first thing that’s been put on bikes that add an external force.

“Before you had what you had, if the balance wasn’t right then the game was over, but now you can add extra force to the bike to help it turn better.

“I can understand why Raul Fernandez [who raced his Trackhouse Aprilia at Phillip Island with its front wings removed] says the bike is easier to ride without wings, because it’s like removing five or ten kilos from the bike, so the bike feels lighter, but with downforce the overall performance of the bike can be improved.

“If you use aero you can take a corner faster because you’re adding force. If you look at the bikes now they look all over the front but in the corners the overall balance of the whole bike is all down. Every motorcycle can turn to the maximum of the sum of the grip of its two tyres, so if you add force to the tyres [and therefore grip] you can turn faster. In general, the aero increases the limit. The bike weighs the same but suddenly you can have five or ten kilos more load just when you need it.”

How did you, the other manufacturers and Dorna work on the 2027 technical rules?

“Dorna asked the opinion of all the manufacturers, so the new rules were developed according to the manufacturers. Dorna explained what they want to achieve and they asked everybody’s opinion, so I think this was the proper way.

“Everybody [computer] modelled what they could. For example, from our side, when there was the discussion to make the bikes narrower, we saw we couldn’t have any aero if we stayed with the four-inline engine. All the manufacturers gave their opinions, Dorna listened and found a compromise.”

So, like you said, one of the reasons you’re building a V4 is because of the new aero rules, also because you have to spend horsepower to create grip.

“Yes, aero eats horsepower, it’s always like this! One of the possible advantages of the V4 is the aero side. When you have rules that reduce the width of the bike then you will have issues if you have a wider engine.

“About V4s making more power, I don’t know if that’s real. On paper, maybe you can, but when we talk to Luca [Marmorini, the former Ferrari F1 engine designer who has worked with Yamaha for several years] he is still convinced that a four-inline can give the same or more power, so I think the main drive to switch to a V4 shouldn’t be horsepower.”

You and Honda are almost not racing at the moment, you’re developing. And you are trying so much new stuff – at tests and at races – that it must get confusing for you and the riders.

“This is one of the bad points of being behind. When I worked with Ross Brawn in Formula 1 [at Ferrari] he always said that if you’re in front and you work properly no one can catch you, because the others need to rush and make tests and try things and make mistakes, but if you are in front and you work in a proper way you just bring something better and better and better and better. I think this is exactly what Ducati is doing now.

“But yeah, so far we are trying to look at the overall picture, which hasn’t been easy with only two riders, but we try not to lose our way, try not to rush things, try not to get excited when something works and not get desperate when something doesn’t work.

“Also, last season the rear tyre casing kept changing, so you also needed to evaluate that, which made everything even more confusing. We are trying not to have too much up and down and we are trying to get a direction. Maybe we test the same things more times at different tracks, trying to get a direction, and for sure we are making the riders slower than they can be at the moment, because that’s how it is.”

Yamaha last won a race in 2022, whereas Ducati went from 2010 to 2016 without a win. I think a lot of people forget that…

“Not me!

“When did you join Ducati?

“I joined in 2004. I was in World Superbike at the beginning and I moved to MotoGP at the end of 2010 [when Valentino Rossi moved to Ducati], so I know! I was there!

“So you know the situation perfectly – coming back from a long way behind. That must be a big help when things look impossible.

“Yes. But I think we are closer now than we [Ducati] were, because the gap was quite big at that time. Now we are basically one second off.

“You need to check and take care of the details. At that moment, the gap was a bit more tough, then at the end of 2014 we got the first concessions: soft slicks, more fuel… People forget! So it’s a cycle, racing is always a cycle, so now we are coming back a little bit. I tell my guys that we [Ducati] worked very, very hard to win the title for nine years from when Gigi joined at the end of 2013. Gigi is very, very good and everyone worked very, very hard and pushed very, very hard. This is racing – it’s quite normal.”

Do you think Gigi and Ducati got lucky in 2016 when Michelin arrived, because the Michelins suit the Desmosedici better than the Bridgestones?

“Yes, sure. I think if we put Bridgestones on the bikes, especially with the Bridgestone front, we [Yamaha] would do better. The switch to Michelin was good for Ducati, even though the front tyre was a disaster at the start. Now Michelin do a great job, so the front tyre is also pretty good, though clearly not the strongest of the two tyres. If you remember the first Michelin test session [at Valencia in November 2015] everybody crashed, even [factory Ducati rider Andrea] Dovizioso. I couldn’t believe it – Dovi crashed! But you’re right – Michelin was good for Ducati.”

Would Michelin’s new front slick [tested several times by MotoGP riders last season] help you now?

“I think it’s still not clear because we tested the tyre and our riders didn’t really like the feeling of that tyre. But I have to say that just looking at the lap times we were very close, closer than before. So if we have a stronger front tyre, I think we could use it somehow.”

You said that racing is in cycles – now MotoGP engineering is Italian, but before that it was Japanese and before that it was European…

“Next year we try to come back and reverse the cycle a bit!”

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