Most perplexing for the Frenchman was that he again struggled to make a step forward during the second weekend at the same track.
Quartararo had the speed to be on pole position for the opening Aragon round, only to plummet to 18th in the race due to soaring front tyre pressure, but qualified just sixth for the follow-up event and finished the race in eighth.
Meanwhile, Petronas Yamaha team-mate Franco Morbidelli won Sunday’s race, using the same medium-medium tyre combination as Quartararo.
“Franco won and made an amazing race with the medium/medium. So the tyre choice was good,” Quartararo said. “And the tyre pressure looks like it was okay.
“The problem was I wanted to do exactly what I did in FP4, make ‘48.4, ‘48.5, but I was losing the grip so aggressively.
“This is why I’m not really happy, because in the warm-up I was so happy about the time that we did.
“I finished with 25 laps on the tyre, doing ‘49.5, ‘49.4. So I was quite confident, but the feeling I had in the race was totally different. No feeling, no grip, no traction. I have no idea why, but it is strange.”
All of which meant Morbidelli, on the A-spec rather than Factory-spec bike, crossed the finish line a massive 14.7s ahead of Quartararo.
“We have more or less the same bike, with the same tyre compounds, so for sure it’s about the riding style but [Morbidelli] did really great. We will need to see why we went that slow in the race,” Quartararo said.
Quartararo wasn’t the only M1 rider to struggle more for speed during the second weekend, with Monster Yamaha’s Maverick Vinales – who fought for a podium at the first race – finishing just ahead of the #20 on Sunday.
“Even in the first week Franco was so consistent, and then he made an improvement. But we made [no] improvement from the first week to the second, and we had no consistency,” Quartararo said.
“Also Maverick, the first week he was so fast. He was the man to beat, but finally he did fourth place and now he finished just a half-a-second in front of me.
“So it’s difficult to understand because, apart from Franco that actually improved a lot, for us whenever there is a double race we [didn’t].”
Quartararo, of course, took victory in both of the season-opening Jerez races, but his winning time was almost identical.
“It looks like in the double races we struggle more because everybody makes a big step and we are just stuck. We are just not doing a step forward,” Quartararo explained.
“Looks like everybody can make more changes and improve but usually when we arrive, apart from here, from FP1, FP2 the bike is already done.
“Like in Barcelona, FP1 was almost already the pace that we had for the race. So this is why we can’t really make step forward. Don’t know exactly why.
“I’m happy to leave Aragon because it was two weeks that we struggled every day.”
With the championship battle nearing its climax, the next venue will also be a double-header, at Valencia, which will begin with Mir, Quartararo, Vinales and Morbidelli all covered by 25 points.
“The positive things is that we didn’t make the same result [18th] as last week, or we would be 40 points behind. Okay, [14 points] is a lot, but there are still three races to go,” he said.
“Now we have double race in Valencia and I’m sure Valencia is a better track for us, with less consumption on the tyre. Because it looks like when we have a lot of consumption, I’m struggling more than the others with the drop.
“So I think that we will be fast and consistent, not like here.
“Then it’s Portimao, which in the past was my favourite track. So I’m really looking forward to seeing the feeling I have with the MotoGP bike.”
Team principal Razlan Razali said: “We need to analyse Fabio’s race and see how we can improve, but other riders also had the same problems that we did. We need to all sit down and see how we can make it better.”