Why V4 MotoGP bikes are better in battles

MotoGP

2020 Austrian MotoGP Insight Part 3: V4s have been the dominant force for years and not only because they make more power. Plus, has KTM built the perfect V4? And Honda’s toughest start in decades

Andrea Dovizioso Jack Miller and Joan Mir during the 2020 MotoGP Austrian Grand Prix at the Red Bull Ring

Two Ducati V4s versus a Suzuki inline-four last Sunday: Dovizioso, Miller and Mir

Ducati

Last weekend’s Austrian GP was the perfect illustration of the difficulties that riders of slower, better-handling inline-four MotoGP bikes face when they are fighting with rivals using faster, poorer-handling V4 machines.

V4 MotoGP bikes make more horsepower because a V4 engine has a stronger crankshaft, less vibration and fewer pumping losses, while inline-four MotoGP bikes are more user-friendly in corners because an inline-four engine has a longer crankshaft.

Some of Sunday’s race was a straight fight between two Suzuki GSX-RR inline-fours and two Ducati Desmosedici V4s. The V4s had the advantage on the straights, while the inline-fours had more speed through the corners, if they had the room to use it.

Yamaha was in a much worse state than Suzuki at Red Bull Ring. While the GSX-RR reached 193.8mph on the run into Turn Two, just 1.6mph slower than the Ducati, the YZR-M1 was 3.7mph slower. These might seem like tiny differences, but MotoGP is so close now that any deficit in any area of performance is a big problem.

Two Yamaha riders qualified on the front row, because M1 riders can cut super-fast qualifying laps on a clear track. But when they get boxed in by faster V4s in a race they’re in trouble.

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What happened to Franco Morbidelli on Sunday was an extreme example of this. Johann Zarco used his Ducati’s superior speed to pass Morbidelli, then blocked his line. And not necessarily on purpose, because by taking a tighter line through the kink his bike naturally drifted to the right.

(It’s also worth adding here that braking in someone’s slipstream is a nightmare. Just as the vacuum created by the leading motorcycle helps the chasing motorcycle accelerate faster, so the lack of wind resistance makes the chasing bike decelerate slower. This is one reason why riders using a slipstream on a straight always move to the left or right of the leading bike when they brake.)

Anyway, back to the story. There are numbers that prove that inline-fours work better alone than in a battle: in the 50 races prior to this season inline-fours fared much better in qualifying than they did in races, taking 17 pole positions against six race victories.

In race situations the superior straight-line speed of V4s isn’t the only problem for inline-fours. V4 machines don’t like corners so much, so their riders use more acute V-shaped lines, braking to the apex, aggressively turning the bike in the middle of the corner and accelerating out. Inline-fours are at their best in the corners, so riders use U-shaped lines, sweeping through in a graceful arc to build as much corner speed as possible.

The V4 rider’s V line allows him to brake deeper, so it’s easier for him to out-brake an inline-four rider than the other way around. And once the V4 is in front, the inline-four can’t use its superior corner speed. And it’s the same leaving the corner – the inline-four rider has lost his corner speed so he can’t commence his corner exit properly.

Basically, inline-fours can be faster than V4s around most racetracks, if they have the track to themselves. But V4s are better fighting bikes. And these days very few MotoGP races are won without a fight.

Joan Mir cornering during the 2020 MotoGP Austrian Grand Prix

Suzuki’s Mir couldn’t use his corner-speed advantage when he had a Ducati in front

Suzuki

On Sunday Álex Rins used his GSX-RR’s corner-speed advantage to take the lead from winner Andrea Dovizioso at half-distance, but he had to push so hard in the only part of the track where corner speed really matters that he lost the front and crashed.

Suzuki team-mate Joan Mir took up the fight. He was all over Jack Miller’s Ducati during the closing stages, visibly faster through the corners, but couldn’t attack, because it was impossible to better the Ducati’s superior straight-line speed and acute corner entries, at least until the penultimate corner.

Credit to Mir for not giving up. Rather than settle for a safe first MotoGP podium he kept the pressure on Miller, which had the Australian take a too-defensive line into Turn Nine, which sent him wide and allowed the Spaniard to squeeze past. Miller wasn’t helped by his choice of a soft front tyre, which was his only choice because he had used up all his medium fronts.

 

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“We have to play our cards because we know our bike isn’t the fastest on the grid but we have a good pace through corner speed and I feel great in braking,” said Mir in Austria. “I can make a couple of metres on the brakes, but it is in the first metres of the exit where you can gain more. Every rider in the top ten knows how to brake late, so it’s more about how you use the bike for the exit, because there’s not many people who do this well. But if we start fighting with the Ducatis it becomes really difficult.”

Fabio Quartararo won the first two races of the year in the only way that really seems to work for an inline-four – get out front as soon as you can and don’t let the V4s get close enough to interfere with your corner speed.

This was how Jorge Lorenzo won the last inline-four championship: bolting from lights-out and running his own race, leading from the first lap to the last in all of his seven victories. It’s significant that this happened in 2015, when Ducati weren’t up to speed and Honda had got its engine spec wrong, causing Marc Márquez problems throughout the year.

There is little doubt that the inline-fours are being helped by Michelin’s 2020 rear slick. Mir crossed the line 1.4 seconds behind Dovizioso on Sunday. Previously the best result by an inline-four at Red Bull Ring had been Lorenzo’s third-place finish in 2016, 3.4 seconds behind winner Andrea Iannone.

Dovizioso wasn’t only happy about his first win of the year, he was also happy that he had reduced his braking issues, caused by the new rear slick, by adapting his riding technique. Not surprisingly, he wouldn’t tell anyone what he is doing differently.

Surely 80 points is an insurmountable gap for Márquez, but these days, who knows?

Meanwhile team-mate Danilo Petrucci struggled to seventh, still struggling with the new rear tyre.

“We are trying to ride with less and less and less engine-braking, to be less dependent on the electronics, because they are not working really good,” said Petrucci. “I always like to ride with a lot of weight on the rear and with a lot of engine-braking, to help me stop the bike. This was, let’s say, my secret when I was fast last year. But this is not possible anymore, because of the construction of the rear tyre, so I have to brake more with the front brake.”

Dovizioso goes into this weekend’s Styrian GP 11 points behind Fabio Quartararo, with the chance to take the championship lead on Sunday. Then it’s back-to-back races at Misano, where the inline-fours should have a much better chance.

And then there’s Marc Márquez. Assuming he returns at the first Misano race he will enter the arena perhaps 80 points behind Dovizioso or Quartararo, with nine races remaining. Surely that’s an insurmountable gap, but these days, who knows?

 

Has KTM found the perfect mix of V4/i4 performance?

Pol Espargaro leads the 2020 MotoGP Austrian Grand Prix at the Red Bull ring

Espargaro and KTM lead the race before the red flags came out

Red Bull

KTM’s 2017, 2018 and 2019 RC16 V4 behaved like most V4 MotoGP bikes – fast into corners, fast out of corners, but a bit of a nightmare in the middle. That’s what horrified Johann Zarco about the bike – trying to get it turned.

This year’s RC16 is nothing like that. “It’s like another world,” says Brad Binder. Either Binder or Pol Espargaró had winning pace at each of the first four races of 2020: at both Jerez rounds, where Binder’s speed was blinding, at Brno, where he won, and at Red Bull Ring, where Espargaró led the race until it was red-flagged. The Spaniard might have done the same in the restart, but he had used up his allocation of his preferred medium rear slicks, so he had to use a soft, which didn’t give the grip he wanted.

The 2020 RC16’s secret is V4-type speed – the machine was the second quickest MotoGP bike on Sunday, at 194.8mph, just 0.6mph down on the Ducati – and much-improved corner speed, similar to the inline-fours.

“Normally with this kind of engine the bike can make less corner speed,” said Espargaró at the weekend. “So we used more of a V-style corner: going to the apex, picking up the bike and using the power to exit fast. But now we have a very good feeling with the front, which allows us to release the brake a bit earlier than we used to, stop the bike where we need to and then carry on for more corner speed. It’s super-nice.”

If the RC16 continues to allow its riders to use more corner speed at upcoming races then we’ll have to assume that KTM has managed to solve the riddle that so far escaped Ducati and Honda. This won’t only be a chassis thing. As usual it will be a combination of factors: getting the chassis right, but also the engine’s off-throttle dynamics and engine-braking strategies, so that riders can roll into corners with extra speed.

Expect to see a lot of Ducati and Honda engineers examining every facet of the RC16’s performance out on track at the next few races, trying to work out what the Austrians have done.

 

Honda’s toughest MotoGP start since 1981

Honda riders Alex Marquez and Stefan Bradl at the 2020 MotoGP Austrian Grand Prix

RC213V riders Alex Márquez and Stefan Bradl together in Austria

Repsol Honda

Honda has endured its toughest start to a grand prix season since the days of the oval-piston NR500 way back in 1981. It all went wrong on day one of the new racing season, when the factory’s top two riders got injured: Cal Crutchlow broke his left scaphoid in warm-up and Marc Márquez fractured his right humerus in the race.

Any factory will be in trouble when it loses its top two riders. “The reality is that we don’t have a top rider… you can’t expect to be always on top,” Repsol Honda boss Alberto Puig told Simon Crafar at Red Bull Ring.

Like Ducati, Honda is struggling with Michelin’s 2020 rear slick, but without one fully fit and fast rider to help adapt its RC213V to the tyre.

Last year Honda had corner-entry issues – remember Marc Márquez crashing out at COTA – which were soon solved. This year’s RC213V seems to have similar issues, most likely exacerbated by the combination of the new rear tyre and possibly extra inertia from the 2020 engine.

“If you can’t brake and then you’re floating in the middle of the corner then it’s always going to be a long race.”

“The inertia is pushing us all the time,” says LCR Honda rider Cal Crutchlow. “It feels like we have a lot of inertia, which is pushing the bike in corner entry, so you have to hold the [front] brake a long time, which makes the rear tyre lose full contact with the road.

“We sort of solved that last year with the 2019 bike, so maybe Taka [Nakagami, who rides 2019-spec Hondas] isn’t having the same problems we are having now.

“It’s all in the deceleration phase, then when you turn the bike and open the throttle you’re on the wrong piece of tarmac, because you haven’t stopped well enough and you haven’t made the corner in a good way. So it’s a vicious circle with braking, turning and exiting the corner.

“With the Honda we can usually gain time in braking, but when we have to brake earlier we lose a second a lap, because making time in the braking zone is the only way to go fast with our bike.

“Whether our problems are due to this year’s rear tyre pushing a lot more [into corners] we don’t know, but I also feel a lot of floating from the rear tyre in the middle of the corner. We need to improve this because it’s a big thing – if you can’t brake and then you’re floating in the middle of the corner then it’s always going to be a long race.”

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No doubt Honda’s problems will largely disappear when Marc Márquez returns to action at Misano next month, because that’s the magic of the man. Give him a problem and he will ride around it, like the rest of us ride around roundabouts.

Márquez was the fastest rider in the season-opening Spanish GP, despite those rear-tyre issues. “The tyre has better grip,” he said during Spanish GP practice. “More grip on corner exits is good, but for us the tyre makes the front push more in corner entry.”

The reigning champion’s ability to manhandle his way around that problem during the race was astonishing, even if it all went awry a few laps before the finish. And who knows if his crash was caused by the rear tyre pushing him into Turn Three? Some pitlane engineers commented at Jerez that the push-in problem was even worse in the ultra-hot conditions, because the front lost grip sooner than the rear, multiplying the problem as the race went on.

On a positive note, whatever KTM has done to its RC16 this year, Pol Espargaro will be able to reveal all to HRC engineers three months from now.