The test ban is over, and the MotoGP season is about to get underway. Bikes are already circulating, as the test riders put the first versions of the 2014 models through a shakedown to ensure that everything is in place, and working the way the engineers intended. In a few hours, we get the first glimpse of what the 2014 season could hold.

The rule changes for 2014, though at first glance relatively small, could have a major impact. For the front runners, the fuel allowance is dropped from 21 to 20 liters, a change requested by the manufacturers to give them the engineering challenge they demand to justify their involvement. All of the Factory Option (the designation for the bikes which have been referred to as factory prototypes for the last two seasons) entries must now use the spec Magneti Marelli ECU, but they retain the ability to develop their own software for the computer which sits at the heart of every modern vehicle. That reduced fuel allowance will place a premium on fuel conservation, meaning the manufacturer who can reduce friction, thermal efficiency and combustion efficiency will hold the upper hand.

It's not just the factory bikes that have a new designation. The CRT category has disappeared, replaced by the Open class. The change is not as big as the renaming would appear. Like the CRT bikes, they have 12 engines instead of 5 to last the season, and 24 liters of fuel to last each race. And like the Factory Option bikes, they must also use the spec Magneti Marelli ECU. The difference, with both the Factory Option bike and last year's CRT machines, is that now they must use the Dorna-controlled software, written by Magneti Marelli to Dorna specifications. The switch to control software means that the claiming rule, which defined the CRT class, has been dropped. Anyone can enter anything in the class, from modified Superbike (as long as, like Aprilia's ART machine, it uses a prototype chassis) to full-fat factory engine, as long as they use the spec software.

What effect will the new rules have on the racing? Less fuel is rarely a positive factor in any form of racing. Of the various ways of limiting performance – engine capacity, rev limits, and fuel flow – fuel limits are invariably the most expensive, both in terms of engine development and in terms of the price riders pay to keep their weight down. As a formula for promoting eating disorders among young men, fuel limits are worryingly effective. Less fuel will favor lighter riders once again, and riders who can create a more efficient aerodynamic shape on the bike. Tucking in behind the screen will become even more important than it was.

Who does having less fuel favor? Of the three manufacturers who have competed with factory status in recent years, it is Honda who have handled fuel best. The combination of an effective engine layout and Honda's reputation for combining maximum power output and fuel efficiency from their engines has seen Honda finishing with fuel to spare, even at notoriously fuel hungry circuits like Motegi. They are not called Honda Motor Company for nothing. Fuel consumption has not been a problem for Ducati either, but the Desmosedici has other problems which vastly outweigh its good fuel consumption.

The fuel limits would appear to hit Yamaha hardest. Yamahas being pushed back to the pits after running out of fuel on the cooling down lap have been a common sight throughout the four-stroke era, and maintaining their competitiveness with a liter less gasoline will only exacerbate that problem. Yamaha's strong point has always been its handling, easier to control, better at braking, turning, and carrying corner speed, but whether they can compensate their disadvantage in fuel consumption through a better-handling bike is open to question. It is an even more pressing question given that Yamaha has also given up its advantage in braking, as the bike has been focused more and more on maintaining corner speed. Only Jorge Lorenzo's sublimely smooth style has kept Yamaha in the race, with the other Yamaha riders struggling with the effects of braking instability with the new, softer construction front Bridgestone introduced in 2012. It was a problem Honda found a solution for in 2013, while Yamaha faced the consequences. They will need some major improvements if Valentino Rossi, Bradley Smith and Pol Espargaro are to get closer to the top three this year.

The first Sepang test will be the first measure of Yamaha's progress. Though the Malaysian track plays more to the strengths of the Honda than the Yamaha – two long straights with a few hard braking zones ensure that – it has plenty of flowing sections where the Yamaha can come into its own. At last year's tests, only Jorge Lorenzo was able to match – and sometimes even beat – the times of the Hondas, while Valentino Rossi and Cal Crutchlow were four tenths of a second or more off the pace of Dani Pedrosa and the remarkable Marc Marquez. If Rossi can be one or two tenths off the pace of Lorenzo, rather than three or four tenths, that will be one sign the bike has improved. It remains a delicate balancing act though, as Yamaha must try to improve braking stability without compromising the bike's corner speed. Like the other Yamaha riders, Lorenzo needs the ability to brake later to defend against attacks from the Hondas or try to pass any RC213V he finds in his way. But if he loses corner speed, there will be little benefit in being able to brake later.

Sepang will also be a key test for Valentino Rossi, regardless of what Yamaha bring. It will be the first test for him with his new crew chief Silvano Galbusera which Galbusera will have had a chance to prepare fully, now that he has spent a couple of months working inside the Yamaha factory MotoGP structure. Rossi needs Yamaha to improve the bike, but he also needs to gauge whether his lack of competitiveness – a relative term, given the record numbers of wins and titles Rossi has racked up over the years – is down to his collaboration with former crew chief Jeremy Burgess, or the fact that his age is starting to work against him. If the gap between Rossi and Lorenzo is larger than the gap between Rossi and Smith, then Rossi will have to start doubting himself. But it is still very, very early.

In the Tech 3 Yamaha team, Smith finds himself facing a fierce rival, with Pol Espargaro moving up to MotoGP. Smith now has a better bike beneath him – on the same spec of machine as Espargaro, much closer to the factory bikes than he had last season – and with a year of experience under his belt, it is time to show what he is capable of. Smith's target will be to be the first satellite rider, chasing the Hondas of Stefan Bradl and Alvaro Bautista. Espargaro has the easier task, focusing purely on getting to grips with the MotoGP class, and adapting his riding style to handle the bike. He made an impressive start at Valencia, and he will be looking to carry this on.

At Honda, all eyes will be on newly-crowned world champion Marc Marquez. Last year, Repsol Honda teammate Dani Pedrosa dominated at the tests, but that was while Marquez was still learning to ride the bike. With a year of experience and the small matter of a world title under his belt, Marquez will look to come out flying. The 2013 Honda RC213V was already a great bike, and the 2014 bike will only get better. The places where the bike is weaker than the Yamaha are a result of the compromises made, and overall, the bike remains a better package. With a liter less fuel, that advantage should be even greater. For Dani Pedrosa, the goal is to try to repeat his form of late 2012, where he dominated the class. He will have his hands full with his teammate and Jorge Lorenzo, but at least Sepang is a track where the Spanish veteran has always shone.

The biggest question marks hang over the garage of Ducati. Test rider Michele Pirro has already put in plenty of laps at Sepang, testing the 2014 version of the Desmosedici against the 2013 bike. Presumably, he will also have been testing the bike running in two configurations, one with the factory software and 20 liters of fuel, and one running in Open configuration with the Dorna software and 24 liters of fuel.

For this is the dilemma which Ducati boss Gigi Dall'Igna faces. He has not had enough time to analyze the problems, develop solutions and then build a bike better than the one left to him by his predecessor. The GP14 is largely a product of the work done by his predecessor, Bernhard Gobmeier, and more changes are likely to be needed. The engine freeze imposed on any entry under the Factory Option rules means that he would be unable to modify the engine in any significant way, and so Dall'Igna is pondering competing under the Open class rules. That would allow Ducati more fuel, more engines, and crucially, the freedom to experiment with engine internals such as crankshaft, valve timing, and even the relative positioning of components, in pursuit of a more compact motor.

Ducati have until 28th February to make their decision. The Sepang 1 test will be crucial, with factory riders Andrea Dovizioso and Cal Crutchlow reported to be ready to do back-to-back tests of the bikes in both configurations. That means that the decision will likely be made in the period between Sepang 1 and Sepang 2, with the second Sepang test being used to develop the bike in the chosen direction.

It seems all but certain that Ducati will follow the Open route. The bike's electronics are the very least of their problems at the moment, and the freedom they gain in development – even chassis changes may require engine mounting points to be modified, something which will be impossible as a Factory Option entry – vastly outweighs the disadvantage of working on software. They can continue that work with the test team, ready for a possible return as a Factory Option team in 2015. But it is possible they could stick with the Open class, if it gives them the advantages they are looking for. That would put the cat among the pigeons, rather as their switch to Bridgestone tires did in the past.

The Sepang test is also the first chance to get a proper look at the Open class. Two bikes appeal most to the imagination. The Yamaha FTR to be raced by Colin Edwards and Aleix Espargaro in the NGM Forward team will provide an interesting comparison of the differences between the Open and Factory Option categories. A 2013-spec satellite Yamaha engine and chassis, in bodywork and other parts produced by Moto2 and Moto3 chassis builder FTR, the bike should benefit most from the extra fuel the Open class is allowed, compensating for Yamaha's traditional weak point. There will be no need to dial back the power – other than saving engine life, as the package being offered by Yamaha consists of just 5 engines, not the 12 allowed under the rules – and so the bike should be able to maintain its speed throughout the race. It will also be a chance to see how the Dorna software compares to the Yamaha, and just how much of an advantage the sophisticated vehicle dynamics packages developed by the factories confer. It will lack the seamless gearbox of the factory Yamahas, but then again, it is still not clear whether the Tech 3 machines will also be using the seamless gearbox in 2014.

The Honda RCV1000R is a different concept, but just as interesting. The production version of the RC213V differs in several aspects, most importantly missing the seamless gearbox of the factory bike. The engine makes less power too, using steel rather than pneumatic valve springs, limiting both engine speed and valve lift duration and profile. But that the underlying concept is strong is clear. The bike may lack speed compared to Yamaha's offering, but it should at least stop and turn. The bike has been designed to get riders closer to the satellite machines, but beating them should be hard.

Those riding the Honda RCV1000R make for an interesting cross section of the MotoGP grid. Nicky Hayden leaves Ducati after five seasons, and will be pleased to find himself on a bike which doesn't suffer the understeer of the Desmosedici. His goal will be to beat the Yamaha FTRs, and harass the satellite machines as closely as possible. His year on the Aspar Honda will provide a glimpse of how much of the 2006 world champion's results in recent years were down to the Ducati, and how much down to him.

At the other end of the spectrum sits Scott Redding. The young Englishman came close to winning the Moto2 title last year, and now he takes on the challenge of MotoGP. More fuel will compensate for his biggest disadvantage – his physical size, the tallest rider on the grid, as well as the heaviest, despite his slim frame – and the RCV1000R is an ideal tool for a rookie season. A chance to get to grips with the Bridgestone tires, and get a handle on racing a MotoGP machine, without the pressure to perform. Redding was still suffering with a wrist injury at Valencia last November, so Sepang is his first chance to ride the bike properly.

The weather here in Sepang is rather balmy, or at least as balmy as a tropical climate allows. Temperatures are expected to remain around the 28° mark, never really rising into the thirties. No rain is predicted, though the sun remains covered by a layer of thin cloud belying the typical tropical humidity. Ideal conditions to go testing. From tomorrow, the 2014 MotoGP season gets underway in earnest. It has been a long wait.