Fuel Pressure Limited In MotoGP. Again.

With the Grand Prix Commission meeting what feels like every race weekend nowadays, it's hardly surprising that readers of the press releases issued get a sense of déjà vu from time to time. Today's FIM press release detailing the latest decision of the Grand Prix Commission is no exception. MotoGP's rule-making body - consisting of the organizers (Dorna), the teams (IRTA), the sanctioning body (FIM) and the manufacturers (MSMA) - introduced new restrictions on fuel pressure, limiting the pressure in fuel lines to a maximum of 10 Bar. If that had a familiar ring to it, it is because exactly the same rule was introduced for 2010 at a previous meeting of the GP Commission back in December of 2009, a rule that was quietly dropped before the start of the 2010 season.

So the fuel pressure limitation is back, but the difference between December 2009 and now is significant. The December '09 announcement merely read "In the MotoGP class the maximum permitted fuel press is 10 Bar." No further explanation or specification was given. This announcement sets out in detail how that maximum pressure is to be limited, including what appears to be a growing trend in MotoGP: an approved part. All fuel regulators must now be approved by MotoGP's Technical Director, Mike Webb, and sealed and certified by the manufacturer. The solution is to introduce what is almost a spec fuel regulator, with the difference being that multiple regulators could be permitted providing they fulfil the technical requirements.

The reintroduction of the rule points up a couple of interesting developments in MotoGP. First and foremost, if the MSMA accepted this regulation - the MSMA has a veto over technical regulations, and is basically in charge of drawing up the technical rules for MotoGP - the there is a very good chance that none of the manufacturers are using a high-pressure fuel injection system at the present.

Secondly, and far more interestingly, it points to the balance of power swinging away from the factories. Dorna, the FIM and IRTA have all been open about their frustration with the current set of technical regulations, which have produced very expensive, electronically regulated MotoGP bikes and sterile racing. It is hoped that the reintroduction of 1000cc bikes will solve part of the problems in that respect, but a second prong of attack comes with the expiry of the MSMA's contract with Dorna to provide the technical rules. Dorna has an agreement with the factories that the MSMA gets to make the technical regulations, which is due to end after the 2011 season. The imposition of a spec fuel pressure regulator could the first step by Dorna and IRTA towards taking the technical rules away from the factories, and casting the MSMA in another role from 2012 onwards. If the MSMA is prepared to accept a spec fuel pressure regulator, then other parts may follow, with the jewel in the crown being a spec ECU. That is currently completely unacceptable to the MSMA - and especially its Japanese members - as the manufacturers get a lot of R&D effort from the data they gather while setting up the complex fueling of a MotoGP bike. As the deadline to renew the MSMA contract draws nearer - and the number of teams expressing an interest in running a CRT effort from 2012 continues to grow - opposition from the manufacturers could be swept aside under a new rule-making regime.

That is going to take some time to work itself out, though. For now, the non-manufacturer members of the GP Commission can be glad that the first blow has been struck in the war that is to come. Here's the text of the Grand Prix Commission announcement, froman FIM press release:

Decision of the Grand Prix Commission

The Grand Prix Commission, composed of Messrs. Carmelo Ezpeleta (Dorna, Chairman), Claude Danis (FIM), Hervé Poncharal (IRTA) and Takanao Tsubouchi (MSMA), in the presence of Ignacio Verneda (FIM Sports Director) and M. Paul Butler (Secretary of the meeting), in a meeting held on 18 September in Alcañiz (Spain), unanimously decided the following:

MotoGP class: 2011 Regulation for fuel pressure

In the MotoGP class the maximum permitted fuel pressure is 10 Bar, at a recirculated flow rate of 50 litres/hour.

1) It is mandatory to use an official approved fuel pressure regulator, as specified by the Technical Director. This official regulator must be fitted downstream of the fuel pump, such that the maximum fuel pressure available to the injectors is never more than 10 Bar.
The official regulator manufacturer may supply regulators set at any lower pressure and/or any higher flow rate, as requested by MotoGP teams, provided that these regulators are not capable of delivering more than 10 Bar at 50 litres/hour.

2) Additional regulators may be used in conjunction with the official regulator to further reduce and control fuel pressure, but no device or strategy capable of increasing fuel pressure at the injectors above 10 Bar may be used anywhere in the system.

3) The approved fuel pressure regulator will be sealed, marked and certified by the regulator manufacturer, and may be inspected and/or removed for testing at any time by the Technical Director.

4) Teams must supply a schematic diagram of their fuel system including the location of the fuel pressure regulator when requested by the Technical Director

5) In measuring the fuel pressure and flow rate delivered by the regulator, the tolerance as specified by the offical approved regulator manufacturer will be taken into account.

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"In the MotoGP class the maximum permitted fuel pressure is 10 Bar, at a recirculated flow rate of 50 litres/hour"

Am I reading this right? Fuel pressure regulator homologation and fuel flow limiting? This is an unexpected twist in the plot. Is this another attempt by the MSMA to find something that makes everyone happy before Dorna lowers the boom?

Honestly, this MotoGP transition is the most confusing thing I've ever read about. If you fuel pressure limit and fuel flow limit you don't need fuel restrictions or bore limits or capacity limits or even 4-stroke rules. So on one side we have Dorna imposing all kinds of performance controls like bore limits, and on the other side we have the MSMA who've just written a rule that could lead to the loosest set of technical regulations since Group C.

When will the governing bodies learn to game or play the Law of Unintended Consequences instead of constantly putting it in play.

It's madness. Even F1 have started to work it out with their rule changes. Surely the fuel limit is easier to police and the knock on effect ios simpler than a stupid pressure limit?

The wording 'no device or strategy capable of increasing fuel pressure at the injectors above 10 Bar may be used anywhere in the system.' is unlike any other rule in F1, WSB, or GP racing. A 'strategy' is never prohibited in the current regulations.

Usually specifications are listed but leave the door wide open to creative system design, such as the current F1 flexible wing mount issue. Yes, my wings are rigid, but the part that mounts to the part they mount to is slightly flexible in a nonlinear way so I pass the limited static deflection tests.

Prohibiting strategies is like legislating the spirit of the rules, so what if I have a 10 bar pressure regulator, if we can find a clever way to get 15bar at the injector I have a legal advantage, right? Wrong in this case. I seem to remember that when F1 ran turbos they had to revise the the relief valve regulations because teams were just overloading it flow-wise and getting temporarily higher boost pressures. Legal, but against the spirit of the rules until the rules were changed mid-season.

Hopefully, as you point out, this is a case of them wetting their feet from a technical perspective and trying to establish simple and clear rules that are easily and cheaply enforceable.


IMO, with the 50 liters/hr they're just defining the test conditions.

If it was indeed *limiting* the flowrate to 50 l/hr, that would effectively limit the 4-strokes to ~170 HP.

IIRC, the fuel pressure limit is to prevent the use of Direct Injection, or at least that was the suspicion at the time...

I've worked the math and it is indeed around 170hp which is far too low to be believable.

Okay, then back to the original post that I deleted. This is merely another ban of direct injection (again) which means that this might be another Suzuki-friendly rule change. If I were to take a guess Suzuki are probably unwilling to spend money to incorporate direct injection. It's an advantage for both fuel economy and temperature control.

Too ready to believe fuel flow limiting. I should have crunched the numbers.

Yes, I immediately thought they changed the rule to block direct injection. Seems a shame that the "premier" class in the world can't use technology that my Aprilia SR50 DiTech scooter has had for 8 years!!!

I'm curious as to what the official explanation of "recirculated flow rate" is.

...Suspicious that this all a ruse, upon closer examination we'll call 'bollocks!'... :-)

Do they mean 'repeatability of the flow rate at constant pressure' ?
Another one is tolerance of the one make regulator. No doubt,if the tolerance and repeatability are rated at say 1%,those with the funding will push the envelope to exploit it to get a constant 10.01 bar pressure to gain a few hundredths over others.
Just give them 25 kg of fuel at temperature X. What next ?

So....to someone like me, who doesnt pretend to understand 100% of what this means. It sounds like another rule, on top of a mountain of rules, that is taking us further away from where we want to go. That being, high horsepower engines w limited electronics. Is that a fair assesment? This rule is bad?

it is a rule to combat another, fighting fire with fire..
why have a fuel limit?

would we need high pressure fuel injection regulation, if the manufacturers weren't so smug about protecting their powerbase? They've bent Carmelo over for too long, and to the detriment of the sport IMO.
Here's hoping this is the start of taking away the conflict of interests that is..the competitors making the rules as they go to protect their self interest.

This is the reintroduction of a rule that was in the rulebook in 2009. It supposedly exists to ban direct injection which means they are really trying to ban stratified charging. If teams start "aiming" the fuel injectors for specific regions within the cylinders, teams would spend millions upon millions to improve fuel efficiency and peak power. The big benefit of stratified charging is that it allows teams to run lean or ultra lean mixtures while still controlling heat.

Direct injection is a cool technology, and I wish they were allowed to use it, but in a fuel-limited formula like MotoGP, stratified charging would increase costs and increase the electronic complication of the fuel injection system.

I am not sure why everyone thinks this is "Bad". It may be sneaky. But this is racing after all.

It is clearly aimed at Direct Injection. Which no one is using at the moment, right? If any of the main manufacturers did develop it, the others would be forced to at least look into it, lest there be a DI gap. Although one can't be sure. Porsche moved to DI in ALMS in 2008 (?), but could still never catch up to Honda, which never did DI and used other methods to make up for the DI advantages.

I read into this a couple of other things:

1) The BIG BOYS are not planning on competing with 800s when the 1000s become legal. If my math is right, there is no way the 800s could compete under these limitations with 1000s.

2) None of the existing manufacturers was planning on using pressures higher than 10 bar, now or in the future, 800 or 1000.

3) The BIG BOYS (Honda, Yamaha, Ducati) are making it harder for any newcomers who wanted to play in this area. Perhaps someone at Honda or Yamaha figured out that BMW or Aprillia was planning on bringing in a DI engine. Or merely that they COULD. Perhaps for fuel economy. Perhaps for temperature control. I would assume that the Big Boys have lots invested in methods already in place that have the same effect as DI already, but do not involve DI. So they would want any newcomers to go through as much pain as they have instead of just letting them use DI.

They don't want to give the new guys an easy out, as it were. And the methods they already have developed probably would not easily transfer to a DI design. They would lose the advantage of the existing R&D.

That's my reading. That's why no one is putting up a stink. They are all in the same boat in an us (Honda, Ducati, Yamaha) vs. them (BMW, Aprillia, fill-in-the-blank) scenario.

Honda have DI, and I'm sure they could equip it quite easily. The other manufacturers could lease it quite easily if they haven't already developed it, IIRC everyone but Honda is already leasing pneumatic valve technology.

DI is uncommon b/c it isn't terribly useful for racing unless the formula is fuel-limited and engine-restricted. MotoGP fits the bill perfectly.

I'm sure Honda would love to spend a truckload of money on DI technology, but the other manufacturers are probably unwilling.

So it seems from my standpoint (and I admit my knowledge is basic at best with respect to DI, or most other tech rules for that matter) that the current manufacturers are trying to stop anyone from entering the paddock from having an equal playing field right off the bat. As if a someone could jump right in and compete consistantly with the big 4(3). It just seems to me that the more rules/restrictions you apply to a situation, the more money you have to spend to squeeze every last drop of performance from the rule. This seems to be counterproductive when trying to attract newcomers to the series. Who wants to join a program when the rules are stacked against them in such a way that there is virtually no chance of being anything other than an also ran?