Honda didn't just have one specification of its all-new 2022 RCV prototype on track at this week's final MotoGP test of the year at Jerez, but two.

No expense has been spared as HRC uses the end of the Covid technical freeze to throw its engineering might behind transforming a bike that, despite two Marc Marquez victories, finished just fourth in the constructors' standings.

Each of the two prototypes, featuring a revised engine, then had different chassis and aerodynamic options to try.

"There are two prototypes, with two different engine setups," explained Pol Espargaro, back in action after withdrawing from the Valencia finale due to rib pain from a massive Saturday practice highside.

"The bikes are both very similar, there are technical things that I cannot tell you, but it's more on the engine side that changes quite a lot.

"Then also in the prototypes we are trying different chassis, and one of them is working really well, and also quite a lot of aerodynamics changes.

"The change is super super big compared to last year [2021], and the knowledge I had from this year is also helping a lot."

Marquez aside, Honda took just one other podium in the hands of team-mate Espargaro this season, compared with two 'non-#93' rostrums during his 2020 injury absence.

With the eight-time world champion sidelined once again, this time by double-vision problems, the need to raise the level of the RCV for all Honda's riders is back in the spotlight.

While Espargaro insisted the main change made to the 2022 prototype, more rear grip, had been a unanimous request and will make the bike 'safer', it's also especially vital for his preferred riding style.

"The potential of the new bike is high, we are generating more rear grip which is already something great," said Espargaro, who rode the 2021 bike on day one before trying the prototypes, eventually finishing the test fourth fastest and top Honda.

"All of the Honda riders, we were struggling with the rear grip. For me, rear grip on the corner entry is so important. Even more than the exit. All the riders were complaining about the exit, me as well, because the exit is about performance.

"But the entry is about safe mode. Now you can make a lot of laps, even with a used tyre, and avoid these highsides on entry. And also you can perform better, because you can stop more [with the rear] when the front is suffering.

"This will mean less crashes from the front, when the front is super stressed."

The Spaniard added: "I can start to ride in the way I like, using more rear brake which for me is super important, it's one of my riding style characters and something I [had] to do less and less this year.

"In KTM I was using the rear brake so much to make the bike turn, especially at the beginning of the project, because the bike was not turning so much. So I was helping so much to stop the bike but especially to make the bike turn, even with some throttle.

"But you know in Honda, we don't have the turning problem. But I still had this method of stopping the bike, especially in the last part with the rear brake, which allows the front to be suffering less. But the problem was I was suffering more from the rear locking on the entry of the corners.

"So this was a big problem, and at the end I had to take out the rear brake quite a lot, and this was killing me so much at the beginning of the year until I got used to not using it so much.

"So now I think we can come back a little and we can be more safe on the entry of the corners, avoiding the closing on the front, plus also more safer in the rear, because we don't lock the rear as much, even using the rear brake more. So this is nice."

Increasing grip at the rear means a new compromise now needs to be found for the front end.

"We still need to play a lot with the balance of the bike. When you gain more rear grip, it's obvious that you push the front tyre more," Espargaro confirmed. "We gain more rear grip, but also we have little bit more wheelie and this sort of things.

"Because as you gain more rear grip, there is more traction and the traction generates other problems.

"But just as we had problems at the beginning of this year with the old bike, and we could improve them throughout the year, I think we need to be good enough to do that again, but just with a very short pre-season with the new bike.

"I think it'll be very important to focus on having a better front grip, especially on the fast areas, to avoid the light feeling at the front."

With a season's worth of RCV experience under his belt, Espargaro feels he can be more effective in terms of feedback to help develop the 2022 bike.

"I'm much better, talking about Honda style, I can ride the bike straight away in a fast mode, without crashing, knowing where is the limit. I'm in another starting point now," he said.

"And this in that way I feel much stronger and also the team can trust me much more in my comments, and they are going to be much clearer, much truer."

And what is asking Honda for by the next test, at Sepang in February?

"Sure, the front needs to be better. As I said, when you gain rear grip, the front struggles a little bit.

"And also power, we are fighting with Ducati, they are going to have a lot of bikes on the grid next year, and if we want to fight with them, we need to overtake them. So we need power to face it.

"So this will be for me the main thing. Because the physical part of the bike is working well."

LCR Honda riders Takaaki Nakagami and Alex Marquez also swapped between the prototype bikes and current RCV during the test, Nakagami being fastest on day one and seventh on day two, when Marquez was tenth.

"We worked on the new bikes. Not like yesterday when we did many laps, we had to share the bikes with Pol and Alex," Nakagami said. "Anyway on lap 4 I was already in '37.6 without pushing really hard. After that we tried to improve the front feeling and it was good. Then after lunch we went back to this year's bike, because we didn't have new bikes. I'm happy!"

"The potential is there, the pace is there and it's nice to ride. This is the most important thing," Alex Marquez added. "I didn't have a lot of time with the prototype today and when I did it was the worst time fo the wind, but it looks like all the riders have the same comments."