The 85th Le Mans 24 Hours kicks off today with all eyes on the big LMP1 battle up at the front between Toyota and Porsche... but it isn't the only big talking point coming into the endurance classic.

Here are other key storylines to watch out for over the 24 hours beyond LMP1

Could the weather decide the race?

It's a question asked on many occasions at the Le Mans 24 Hours though it is usually associated with rain... however, this year it is the 'big yellow thing in the sky' that could become cause for concern for the teams.

Since our arrival on Monday we have barely seen a cloud and temperatures have soared well past 30 degrees. Forecasts suggest they will continue to do so on Saturday and Sunday.

This is significant for two reasons: Firstly, teams had anticipated cool conditions once the sun goes down (around 6 or 7 degrees) but temperatures are not expected to dip below 18 degrees even at 2am. For a graveyard shift in the car, it will likely be more stressful for drivers, engines and tyres than teams are used to.

Secondly, there is a regulation in place that stipulates drivers are not allowed to spend more than 80mins in the car at any one time if air temperatures outside the car are considered excessive (over 32 degrees we understand). This could affect strategies as that 80mins mark comes between stints, which means there will be more driver changes - which generally isn't favoured by teams or drivers as it means fewer prolonged rest periods.

Though it is unlikely to affect the drivers once the race gets underway, it could well prove so in the closing stages of the race when 3pm on Sunday rolls around.

Furthermore, only Porsche features air conditioning in its car, while Toyota makes do with air vents that allow circulation but not cooling.

Definitely one to watch.

Cartoon hero Michel Vaillant jumps from fiction to reality

The cartoon racing hero comes to life for his 60th anniversary race as part of the Rebellion Racing team, which has entered a pair of LMP2 Orecas in his name. The iconic (and ageless) character has enthralled loyal and enthusiastic fans with the trials and tribulations of his and the Valliante's Racing team's fictional motorsport career, which has seen them compete in F1, rallying, F3 and of course Le Mans over the last six decades. To celebrate the launch of his latest adventure - conveniently named Rebellion -, the Swiss team will run in Vaillante Racing's blue, red and white colours.

The Oreca of Nelson Piquet, Mathias Beche and David Heinemeier-Hansson will be the one to watch in particular as it will run in #13, the same used by Vaillant because it is the number racers 'daren't wear'.

This isn't the first Vaillante Racing liveried car to blur the lines between reality and fiction following similar efforts at Le Mans in 1997 and 2002, but this one stands a very good chance of LMP2 victory. Now that would make a good story.

The experienced first timers

There are a number of rookies making their Le Mans 24 Hours debut this weekend but it doesn't mean they don't bring a wealth of experience with them already.

In fact, in F1 terms they can't possibly get more experienced than Rubens Barrichello whose 322 starts between 1992 and 2011 continues to single him out as having the greatest longevity at the top of the sport. Nevertheless, 25 years after he made first F1 start the 45 year-old will take to the start of Le Mans for the very first time in the Racing Team Nederland LMP2 Dallara.

Though the Dallara - with its incredible 210mph top speeds but tricky handling - is unlikely to match the rival LMP2 Orecas come the race, you cannot miss the yellow Jumbo-liveried car out on track and it has swiftly become a fan favourite here. Better still, Barrichello shares his car with former Le Mans winner Jan Lammers, who made his F1 debut in 1979 and completed his last race in 1992 just as his co-driver was starting his career.

Elsewhere, IndyCar star Tony Kanaan makes his Le Mans 24 Hours debut in the Ford GT after a late call up to replace the injured Sebastien Bourdais, though the Brazilian is an experienced hand in endurance sportscar racing following wins at the Daytona 24 Hours.

Other high-profile racers hoping to get to the end of their first Le Mans include triple WTCC champion Jose Maria Lopez, former GP3 winner Alex Lynn, Formula E standout Felix Rosenqvist and ex-F1 driver Jean-Eric Vergne,.

ByKolles for the podium?

There weren't many items to cherry pick from the ill-fasted Nissan LM GTR NISMO when the project was canned after just one race appearance at the end of 2015, but at least the ByKolles Racing team managed to get the best bit - the engine.

The plucky privateer team deserves a good Le Mans this time after last year's fiery conclusion but while you won't see the car rivalling any of the factory LMP1 cars on pace alone, the dip in entries this year in theory means it will require only three of them to fall by the wayside for it to get onto the podium.

Indeed, ByKolles with its mouthful of a ENSO CLM P1/01 car is enjoying its best patch of form at the moment, which is just as well as the rapid LMP2 cars are nipping at its wheels enough to ensure it could have a race just to keep ahead of them.

Though indifferent reliability this week means it will take some good fortune for it to use that angle to get the better of Porsche and Toyota this weekend, with more - better funded - privateers set to shore up the LMP1 ranks next year, this is arguably ByKolles' best ever chance to create an upset.

Sandbags or windbags?

Five manufacturers, 13 cars, a quality line-up of drivers - the GTE Pro class may not be as spectacular as the prototypes but this is set to be the most closely-contested category when the flag falls at 3pm.

Based on qualifying (and some constant BoP tweaks) the five cars - Ford GT, Aston Martin V8 Vantage, Porsche 911, Corvette C7R and Ferrari 488 GTE - are remarkably evenly matched but each manufacturer is suspicious of the other at the moment.

Ford is the main culprit for this after last year it was widely criticised for perceived sandbagging in the run up to Le Mans with its new GT to ensure it ducked out of those Balance of Performance changes.

Teams are now worried it is committing a similar (legal) crime having been unusually off the pace before qualifying, before finding some good pace when it mattered in the final session.

The Ford drivers have strenuously denied the accusations but it has found a lot of time over the week so far and another win 12 months after its 2016 success wouldn't be surprised.

The arrival, disappearance and return of Ben Hanley

Roll back to 2008 and Ben Hanley was considered one of Britain's best hopes behind the wheel having finished runner-up to Alvaro Parente in the World Series by Renault, allowing him to step up to the GP2 Series.

However, despite taking a podium in the Asia portion of the series, Hanley exited the series mid-way through the season and - to a large extent - has not been seen on the international motorsport stage since.

Instead, Hanley returned to the World Karting Championship, where he has maintained his relatively low profile in recent years. That is until recently when - after landing a DTM test for Audi - he competed in the European Le Mans Series last year.

This season sees him make a very long awaited Le Mans 24 Hours debut aged 31 with the DragonSpeed team alongside Felix Rosenqvist, another driver seeking a shot at the big time having impressed in Formula 3.

Even the amateurs are rapid

Le Mans may be known for its 'gentlemen' racers mixing it with the bonafide professionals, but this year's GTE Am class is slowly blurring the lines between those that do this for a living and those that, well, don't.

The ultra-experienced Pedro Lamy - a two-time overall podium winner at Le Mans - continues in this class driving the 'orange numbered' Aston Martin alongside 'amateurs' Paul Dalla Lana and Mathias Lauda, the nephew of F1 champion Niki getting his chance in the car after having his classification demoted to 'bronze' despite previously raced in DTM and GP2.

Another to watch out for Fernando Rees, who was one of the quickest drivers in the GTE Pro class driving an Aston Martin before joining the Larbre Competition team driving an 'Am' Corvette. In fact, with its lurid 'graffiti' style Art Car livery, you can't miss him anyway.

Finally, Will Stevens - who raced with Manor in F1 as recently as 2015 - drives the JMW Ferrari 488 GTE having made his Le Mans debut a year ago driving a Manor Oreca LMP2. It is also worth pointing out his team-mate Dries Vanthoor, whose brother Laurens was being tipped for a move into the Audi LMP1 line-up before its withdrawal having won the Blancpain Sportscar series.