Aprilia tech: The tyre-pressure rule is ‘gambling, it’s not motor sport’

MotoGP

Aprilia chief engineer Romano Albesiano shares his thoughts on MotoGP’s controversial tyre-pressure rule, how the RS-GP keeps improving, why it’s so difficult to beat Ducati and how he started working on downforce aero in the 1990s

Espargaró Aprilia 2023

Last year Espargaró was the first rider to be penalised for low front-tyre pressure, all because his rear tyre went off during the Indonesian GP

Aprilia

Mat Oxley

In 2024 Aprilia aims to take the next step towards challenging MotoGP dominators Ducati. Chief engineer Romano Albesiano knows this won’t be easy and the challenge isn’t made any easier by MotoGP’s controversial tyre-pressure rules, enforced for the first time midway through last season.

Aprilia’s Aleix Espargaró was the first rider to be penalised for running below the minimum front pressure of 1.88 bar. He was under in October’s Indonesian Grand Prix (first offence, warning only) and again in the Thai GP (second offence, three-second penalty).

The circumstances of Espargaró’s ‘offence’ once again highlight the arbitrary nature of this regulation. The Spaniard’s front tyre only went under pressure in Indonesia because his rear tyre was “dead” from half-distance. This forced him to slow down, which reduced front-tyre temperature and pressure, hence the infraction and the penalty in Thailand.

In other words, riders are punished even if they and their team have done nothing wrong. And this year the penalty is increased to instant disqualification, from the first offence. No wonder Albesiano and others want the rule changed.

Last season was Aprilia’s fourth with its game-changing 90-degree V4 RS-GP. The move from a narrow 75-degree vee angle to 90-degrees, like the Ducati, Honda and KTM (OK, the RC16 is 86 degrees) transformed the RS-GP from top-ten hopeful to winner.

The bike won its first MotoGP race in 2022 and took two more victories last year, at Silverstone and Catalunya, where Aprilia took its first one-two, with Espargaró ahead of team-mate Maverick Viñales. The bike also scored eight front-row starts, including two poles, one each for Espargaró and Viñales. Aprilia finished third in the constructors championship, behind Ducati and KTM.

Aprilia Ox 2

Albesiano and Espargaró have worked together since 2017, taking the RS-GP from top-ten battler to race winner

Espargaró praised the 2023 RS-GP’s speed and its improved stability and turning performance. For 2024 he wants better braking, although Albesiano isn’t sure this is a purely bike-design issue. One factor Albesiano (who started out as an aeronautical engineer) is sure about is heat – the RS-GP cooked its riders at hotter races last season, so his engineers are working on fixing that for 2024.

There’s no doubt that the RS-GP could challenge for the title, if the factory team and Trackhouse (which has taken over Aprilia’s independent team from RNF, retaining riders Miguel Oliveira and Raul Fernandez) can better focus on set-up and fine-tuning the bike for each racetrack.

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Oxley: Some people expected you to challenge for the 2023 title, but you didn’t, so how do you analyse last season?

Albesiano: The bike was competitive at almost every track, whereas in 2022 we had some tracks, like black holes, where we were clearly not competitive. Last season we went to those same tracks and were absolutely competitive. This is a process that we started in 2021, so we are covering the map more and more.

For example in 2022 we had a terrible crisis with grip at some of the races in Asia, like Chang [aka Buriram] and Sepang. Last season Chang was super-positive for us [Espargaró qualified on the front row].

What explains the grip crisis you had at the end of 2022?

It was a matter of grip, pure grip, but it’s difficult to explain why.

In 2023 we were also super-competitive at Spielberg [Red Bull Ring, where Viñales qualified second], which means we improved braking. So I think the process of closing the gap to the top is still in process.

Then we had some more ups and downs, which I’d say came from bad luck – injuries. For example, it wasn’t discussed much but the injury Aleix got in Mugello, where he crashed his bicycle and broke his feet, affected a few races. And then again at the end of the season, when he got hurt in Qatar. But from a purely technical point of view I’m happy.

Aprilia MotoGP 2023

Aprilia scored its first one-two at Catalunya last September: Espargaró first, Viñales second

Aprilia

What will it take to challenge for the title?

Being the leader at this moment is very difficult because Ducati is very strong – they are a great organisation, they have a great bike and a great number of bikes on track, which helps a lot.

And it’s not just that they get a lot of data from their eight bikes, it’s also the software that they have to crunch through that data very quickly.

This is very helpful for them. We started this process last year with our first satellite team [which doubled Aprilia’s data acquisition]. We are quite behind in this process but, OK, it’s important to have started it. We’ve already had some fruit from this, but again we had some horrible luck, with Miguel’s injuries.

l always remember the first corner of the first lap of the first GP of 2023 – the guy who was in first position was Miguel. Then after a few laps the worst thing happened [Oliveira was taken out by Marc Márquez]. And then again, two-thirds of the way through the season he was a bit nervous with all the discussion of him replacing another rider in another company [Márquez at Honda]. But he showed that when everything was right he was very competitive.

You said you had problems with grip at the end of 2022 but last season you got your first one-two at Catalunya, which is very slippery. So does your bike work better with less grip or more?

Honestly, many people say they understood everything, but honestly sometimes it looks like we are strong where the grip is poor and other times we need a lot of grip to be competitive. So it changes and we need to understand the facts. Maybe we are starting to understand these things better, but still not fully.

Aprilia Oxley 2024

Aprilia has yet to race its carbon-fibre/aluminium composite frame but the frame may be raced during the 2024 season

Oxley

Usually the Aprilia is best at flowing circuits, not stop-and-go circuits…

But again, Maverick almost got pole at Spielberg and he did get pole at Valencia. And we were fast at Chang and Motegi, which are both big braking tracks. It’s not the bike itself – at least 50% is how you set the bike.

You usually run bigger discs than Ducati – to get the bike stopped?

This is related to the working temperature of the discs, to the way we cool them down: the position of the discs, more internal, more external, so it’s more of an aero thing, the way you cool the discs.

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Aleix says he wants more low-rpm torque for 2024 – how will you fix that – better combustion or what?

Ah [laughter], honestly, we are not missing low-rpm torque. The rider feels a lack of torque when the traction control cuts the available torque. In MotoGP there are very few corners where a MotoGP engine lacks torque!

What happened with the [electronically actuated] clutch and start system you that were told to take off the bike following a clarification of the rules?

We started using a carbon clutch a couple of years ago and we struggled a lot. This system helped the rider to counteract the, let’s say, the not-optimum behaviour of the clutch. Honestly, the regulation was really difficult to interpret, but we accepted the clarification and removed the system. Now we have improved the function of the clutch itself and it’s working quite well.

You were the first factory to get penalised for running below the minimum front-tyre pressure, so is this an issue for you?

Aleix got a warning in Indonesia because the rear tyre was dead from the middle of the race, so he couldn’t push anymore and he finished the race going very slowly — that’s why the front pressure went down so much. Then Aleix got the penalty in Chang for point zero zero nothing.

The riders ask their crew chiefs, ‘Please keep the pressure low because the front tyre works better’, then the crew chief tries to do the best he can. At Chang the conditions changed for the race, and we were just slightly under, so I don’t think we have a real issue there and we have the tools to manage the situation.

Aprilia Ferrari MotoGp 2023

Aprilia hired aerodynamicists from Ferrari’s F1 team and may have the best aero in MotoGP. It was the first bike with fork wings, at the start of 2023, and everyone followed

Oxley

Basically you have to predict the future to stay on the right side of this rule – it must drive you and your engineers crazy…

Yes, absolutely. You must assume, especially in cold temperatures, that you will race alone, that you won’t be in someone’s slipstream. If you assume that you will probably be in someone’s slipstream, that you will be in a group, then you can take a risk [and start with a slightly lower pressure]. But it’s gambling, it’s not motor sport.

I think Michelin should consider giving us a bit more margin [by lowering the minimum]. No one wants the responsibility of their product causing an incident, but it’s been widely proven that you can run lower than 1.88 bar.

What about the issue of cooking your riders?

Definitely, yes. The 2023 bike was better than the 2022 bike, but clearly not enough. We are designing the 2024 bike by routing the hot flows in different ways. Before, maybe we privileged too much the efficiency of the motorcycle and we considered, OK, the riders are well paid for suffering a little [laughter], but maybe it was a bit too much!

Last season you started testing a carbon-fibre frame – how is testing going and when will we see the frame at a race?

We will keep testing the frame, which so far has shown some advantages and some negatives.

The first advantage is weight. Then you can define the stiffness in any way you like – it’s another planet! But it’s not a short-term project, so we will keep testing it and when it’s mature, maybe we will do some races this year, maybe some wild cards.

Aprilia’s 2023 aero upgrade arrived at Silverstone.

Aprilia’s 2023 aero upgrade arrived at Silverstone. A small wing (at the bottom of the l of Aprilia) protrudes from each side of the RS-GP’s fairing to better control the airflow for increased rear downforce and therefore better turning

Oxley

KTM has made the biggest steps forward in recent seasons by hiring numerous staff from Ducati, so they are doing it the Formula 1 way, by hiring brain power from the best brand. Why don’t you do the same?

We have our way which is giving results. We believe in the way we are developing. Sometimes we take people from other companies, but I don’t think we really need to do lots of this.

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KTM – from what I understand from the outside – have really changed the company. They are still orange but inside is different. I don’t think we need to make that kind of process. Of course we respect all the manufacturers and we have to learn from everybody, but we don’t need a revolution inside Aprilia.

Also I think KTM made a good 2023 season by exploiting very much their starting system in the first races – they had an unbelievable performance in starting [until Ducati caught up with its upgraded start device, introduced after the summer break]. This fixed many races for them and in the end this gave them the result in the constructors’ championship [KTM finished second, behind Ducati and in front of Aprilia.], but if you take out this factor, I’m not sure.

Way back in 2011 I interviewed John Barnard [the renowned Formula 1 engineer who created F1’s first carbon-fibre chassis and other innovative technologies] and we got talking about downforce aerodynamics.

He told me, ‘When you’ve got 60 degrees of lean you’ve got a lot of fairing close to the ground, so what’s that doing and what could it do is another question…’. In other words he was already talking about the ground-effect fairing you introduced in 2022!

In fact this was already our dream in the 1990s [when Albesiano designed chassis for Cagiva’s 500 GP bikes], when we put this kind of thing in our simple simulation models, so it’s not new.

Oxley The prototype 2024 RS-GP at November’s Valencia tests

The prototype 2024 RS-GP at November’s Valencia tests – no huge differences, so Aprilia is at the stage where it’s tweaking the details to make that last step

Oxley

I spoke to Barnard again recently and he said the next step should be skirts to better control the airflow under the fairing and increase ground effect…

This isn’t allowed because you cannot have parts protruding from that part of the fairing. If you look at our fairing you can already see some ridges [introduced at Silverstone last year], which are exactly that kind of thing [for controlling airflow], because when they approach the ground you get negative pressure. But otherwise this kind of thing isn’t allowed.

When I worked at Mercedes AMG in DTM [Deutsche Tourenwagen Meisterschaft – a European sports car series] in 1995 and 1996 we went to Nürburgring and the rules, people used to say, were ‘alive’! Alfa arrived with proper skirts touching the ground and they were allowed. So we went back to the wind tunnel and put some aluminium tape and aero-wire on the wind-tunnel model of our car and it was unbelievable. When the speed went up the car was sucked into the ground, but you can’t do this on a motorcycle.

I suppose too much ground-effect would be bad on a motorcycle – the bike would be unbalanced because the negative pressure is to one side of the tyre contact patch and quite far away from the contact patch.

Yes, it would be unbalanced. On a racing car you have a map of aerodynamic force which is a function of front and rear height. Even small changes control this force and on a motorcycle you wouldn’t be able to optimise the downforce.