Bridgestone Press Release: Shinji Aoki Explains Why Everyone Used The Soft Rear Tire At Barcelona

As is the case after every race weekend, Bridgestone today issued their post-race debrief press release, with the Japanese tire company's view of the weekend. With tires a subject of constant discussion during the weekend, there is much to talk about, but the most intriguing nugget of information in this press release comes in Aoki's explanation of why all of the prototype riders went for the soft rear tire, and the role which electronics and set up has come to play in determining tire choice. With this in mind, Bridgestone brought a new rear tire to be tested at Barcelona on Monday, and Aoki explains Bridgestone goal with this new rear tire. The press release appears below:

Catalan MotoGP™ debrief with Shinji Aoki
Thursday 20 June 2013

Bridgestone slick compounds available: Front: Medium & Hard. Rear: Soft, Medium & Hard (Asymmetric)
Bridgestone wet tyre compounds available: Hard (Main), Soft (Alternative)

Yamaha Factory Racing’s Jorge Lorenzo rode peerlessly under pressure to win last Sunday’s Catalan Grand Prix ahead of the Repsol Honda duo of Dani Pedrosa and Marc Marquez.

Tyres were a major talking point over the race weekend, with hot conditions setting track temperatures soaring with a peak of 57°C during Sunday’s race that tested the tyres to the limit. Despite the scorching conditions, the overall race pace was improved on last year and in qualifying, Repsol Honda’s Dani Pedrosa recorded a lap-time of 1’40.893 seconds, smashing the old pole position record set by Casey Stoner with qualifying tyres in 2008.

Q&A with Shinji Aoki - Manager, Bridgestone Motorsport Tyre Development Department

Montmeló experienced very hot temperatures last Sunday. What affect did this have on tyre performance and race tyre choice?

“Indeed, the whole of the race weekend saw very high track temperatures with peak recordings reaching almost 60°C. The Wednesday before the race we modified our tyre allocation for the race to provide our two hardest compound front slicks as we knew conditions were going to be extremely harsh on tyres. The very high temperatures affected tyre performance by making the track quite greasy and also increasing tyre wear. Over short runs, we could see that outright tyre performance was very good, with Dani setting a new circuit best lap time in qualifying. The race pace was also better than last year, but we did see that over race distances that tyre performance was compromised somewhat by the extreme heat.

“The scorching conditions ultimately didn’t affect race tyre choice greatly, rather tyre choice revolved around choosing options that best suited the characteristics of the circuit where the riders spend a lot of time at large lean angles. As a result, all but one rider selected the hard compound front slick, as this specification offers greater cornering stability, with the bonus of greater durability. This same factor of the riders spending a lot of times banked over in the corners was also why most riders preferred the softer rear slick option, as they want the highest level of grip from the edge of the rear tyre when they are leaned over in corners.”

With such high temperatures on race day, were you surprised that no riders selected the hard compound rear slick option?

“We did expect that in the very hot conditions that some works riders would select the harder rear option, but this didn’t happen so we can’t say if this option would have performed better over the race distance. We did see many riders evaluate the hard compound rear slick earlier in the race weekend, often at a competitive race pace, but come the race all the works riders went for the softer option. The riders always want as much grip as possible from the edge of the rear tyre as they feel that having good pace at the beginning of the race is very important for the race result. With this in mind, they will use the softest slick available and find a way to manage it effectively over the race distance.

“This is a trend that is quite noticeable this year; that even in very hot conditions riders are working hard during the practice sessions to find a way to make the softer rear slick work for the race. What is obvious is that progress in electronic management systems, motorcycle setup, and the riding style of the riders has evolved to a point that riders can effectively use softer rear tyres in almost any scenario. If they can manage the durability of the soft compound, there is no reason to use the hard compound. As a result we are now developing experimental rear slicks to see if we can broaden the effective operating range of our hard compound slick tyres.”

What development is Bridgestone undertaking to create a new hard compound rear slick tyre that will be more desirable for the riders?

“Our MotoGP tyre development program is constantly developing new experimental tyres, and at the post-race test at Montmeló on Monday we tested a new hard compound rear tyre. The rider feedback regarding this latest evolution of tyre is that it is a big step in the right direction, so we will continue working down this development path. We are also considering other technological developments in regards to the rubber compounds of our rear slick tyres that we plan on providing for testing purposes later this year. Once we get a general consensus from riders on what works best, we can then consider introducing a new hard rear slick option into our tyre allocation. In the meantime, we will work closely with Dorna and the FIM to see how we can best use our current range of tyres to ensure all the riders on the grid have a tyre allocation that works best for each circuit.”

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Even with tyre competition the progress made with GPS traction control makes it an off-track competition for the top places.
Time to remove the option and make them use their right hands.
'Take your brain out' was a term for a brave and committed lap. Now it means rely on the black box under your cojones.
Not good for competition and not even that good a spectacle when you know that the powerslide is now being controlled by the computer too. Impressive, but not awe-inspiring.

In his column, Bradley Smith explained how he never really used the electronics, until he rode in wet conditions. Apparently he never actually needed them in the dry.
Jonathan Rea, after his try in MotoGP said that as the race was progressing, he noted that he had to turn down traction control (TC), instead of up, because otherwise the TC would cut too much power and slow him down. To me, this indicates that the rider still needs lots of skills.
Marquez and Rea said that they checked Pedrosa's data, which helped him figure out how Pedrosa rides some corners. Rea, after returning to WSBK said that he never really used the back brake but after seeing the MotoGP guys using it, he was also using it a lot to help the bike turn into corners. This indicates rider skills, not just electronics.
Marquez and Stoner are rumored to be using not so much electronics. There is really no way of checking if Pedrosa uses more and for what. All 3 are very fast riders.
Pedrosa, Rossi and Colin Edwards at a certain point asked for a wall, essentially, so that they would not share data and settings.
From all of this, I conclude that the electronics are not everything. They help, but it's still in the rider to actually use it to his advantage. They are a huge advantage, since now riders can turn out a race distance of near perfect laps.
By the way, GPS data is forbidden, they use algorithms to figure out where they are in the track.

Back on subject, I am happy to see that Bridgestone is making changes to his tyres. Hopefully, in the short future, riders may choose to use the hard compound for the rear. Hopefully, the new tyres will also have the added benefit of being “easier” to extract all performance from them. Spies was saying that tyres are part of the reason why the "show" is missing. Tyres are so good, that they are actually very hard to extract all performance from them.

Is a relative thing - I struggle to even comprehend what these guys do to get a bike around a circuit and the speed at which they do it.
Your point on GPS is noted - I almost said 'turn by turn'.

The principle is the same though - what I am advocating is at least a lower level of electronics, more like a road bike, so that the track/tyre/weather can be allowed for but the rider is in control and the electronics are a 'safety net'. I would prefer a BSB type approach where traction control is outlawed (and highsides have not been a problem) but leave that to the organisers to decide what is realistically possible/safe.

My main point is that when riders/teams use a tyre that can only be managed by the electronics it's time for a change/simplification.

"... are rumored to be using not so much electronics" - writes gunbalina. While I cannot speak for the former, with regard to he later, there is no rumour involved. His various team-mates marvelled at it when they saw his data, as has the HRC vice-president on at least two occasions in interviews.

So while Rossi dubbed Stoner "the traction control kid" in 2007, which was seized upon by the very gullible (and malleable) European press and turned into a 'truth' (Joseph Goebbels eat your heart out), in fact it was the complete opposite of the truth.

How do you explain the close up video shots of Stoner hitting the apex and then slamming the throttle wide open ? I remember commentators talking about it in 2007...

I have asked several people about this. Nicky Hayden, who was Stoner's teammate, said that Stoner had incredibly sensitive throttle control, especially in the last 8 or 9% of the throttle (exactly what would look like 'slamming the throttle open', only it isn't going wide open, it is going to exactly the right spot where there is still traction). Cristian Gabarrini and Lucio Cecchinello both said that Stoner had an incredibly sensitive sense for the throttle, and that he had his electronics set up to interfere much, much less than most riders. Shuhei Nakamoto attributes the renaissance of Dani Pedrosa to the Spaniard seeing just how little electronics Stoner used, and understanding that he could do that too. Stoner was always at war with his electronics guy, asking for less and less. (Incidentally, Marc Marquez is going through the same process now).

It is a complete myth, and completely false, that Casey Stoner relied on electronic control. Normally, I delete comments referring to this, but a couple of times a year I leave a reply similar to this one, for those who have not been paying attention for the past five years.

"(exactly what would look like 'slamming the throttle open', only it isn't going wide open, it is going to exactly the right spot where there is still traction)"...he fooled me then and I'm sure (back in '07) that I remember commentators talking about it ? Am I mistaken about that too ?
(My comment wasn't about his time at Honda)

The commentators could not see what was going on, and fell for the spin being provided by those in the paddock with an axe to grind. They repeated what they were told, and viewers believed what they heard on TV.

Of course, what makes this even more difficult is the fact that the difference between 100% throttle and 92% throttle on a 1/4 turn racing throttle is just a few degrees of rotation. If you can spot that on the TV, then you should probably be working for military intelligence pouring over spy photos.