If Ducati riders claim a MotoGP race win, two second places or three podiums in dry conditions this season, their maximum fuel tank capacity will be reduced from 24 to 22 litres.

The rule does not apply to any other machines, but Nicky Hayden has revealed he is already 'limited' to 22 litres on his Open Honda.

"This tank doesn't even hold 24 litres, it's 22 litres, so I don't expect the extra fuel [load] to make a huge difference in the race," the Drive M7 Aspar rider said on Friday night in Qatar.

The fact that the Open Honda, a 'for sale' machine, needs less than 22 litres to finish even the most fuel hungry race at maximum power underlines its present level of engine performance.

The pace setting Open Yamaha of Aleix Espargaro is able to make use of 23-24 litres. Ducati states that its fuel tank is around 22-23 litres. However this is not an equal comparison since - unlike the 'normal' Open class, which runs the standard ECU software - Ducati also has all the fuel-efficiency tricks available from its advanced factory software.

Indeed, Ducati Corse general manager Gigi Dall'Igna had warned they would need to cut power if forced to race with 22.5 litres and the Open ECU software: "You have to remember that the [Open] software does not have all the strategies to reduce fuel consumption. So 22.5 litres is not too much. For sure we would have to cut the power, not in all races, but in some races. So for us it is an important performance reduction."

Fortunately for Ducati this proposal was not adopted and they were allowed to keep their Factory software. The Factory class Honda and Yamahas are limited to just 20 litres this season, one less than last year.

Hayden's average top speed was only 3-4km/h slower than the Forward Yamahas on Friday - but 20km/h below the peak average by Pramac Ducati's Andrea Iannone. Having raced for Ducati in recent years Hayden had the advantage of superior top speed when battling in the pack. This will no longer be the case.

"It will be really tough [to overtake], at least on the Ducati when you were close to someone you could nip them on a straightaway but that's not going to happen here unless it's an Aprilia or something."

The American - the quickest Open Honda throughout winter testing and the grand prix event so far - finished Friday night 13th fastest, 1.6s off the pace, and admitted there is little room for further improvement this weekend.

"We didn't improve a lot because we tested here for three days, so we don't have a lot of new stuff that we can try, but in the session we made a slight change in the geometry that helped and the bike tracked slightly better. But it's not a huge step. Position wise and gap wise we're probably a little worse, but we knew that on the second night everyone else would improve a lot."

Friday practice also saw spots of rain, then a much heavier downpour overnight. Just as in 2009 the prospect of a wet race is on the cards and Hayden confirmed that if it rains the grand prix will be stopped.

"The rain was very light [in FP3] and truthfully I couldn't feel it on the ground because it's so hot. But you see it on your shield and visor and with how fast we're going it messes with your head. I hope it's not like that in the race though. In the riders meeting on Thursday they said that we won't run in the rain so I'll need to find out what level of rain would stop a session but today wouldn't be enough to stop the race."

The weather is a further example of why nothing is certain until the chequered flag falls on Sunday.

"The first race of the season is always interesting and you don't know what to expect," said Hayden. "There's a few new guys in MotoGP that you've never seen on track until you race, and some guys on different bikes as well."