Jack Miller Plays Down Yamaha Sepang Test Disruption

MotoGP, Sportrik Media - Jack Miller has downplayed the significance of Yamaha’s absence on day two of the official Sepang MotoGP test, insisting the technical “hiccup” that halted V4 running was a normal part of developing a brand-new machine.

The Prima Pramac Racing rider had previously put Yamaha’s V4 at the top of the timesheets for the first time during day two of the Shakedown, before opening the official test in 14th position, 1.406 seconds behind reigning world champion Marc Marquez. However, Yamaha’s plan to shift focus from testing new components to establishing a base set-up was interrupted after technical issues affecting Fabio Quartararo and Toprak Razgatlioglu on day one prompted the manufacturer to stop all track activity on day two.

Following overnight investigations involving Yamaha engineers in Japan and Italy, the manufacturer received clearance to resume running on the final day of the test, albeit with a reduced programme.

“It’s a hiccup, but it is what it is,” Miller said.
“You’d be extremely naive to think you could build a bike in nine months to race against the best in the world and not have a day like we had yesterday. It’s par for the course.”

Miller highlighted the scale of the response from Yamaha’s global technical operation in resolving the issue.

“The boys busted their arse last night to find a solution and get us back on track,” he added.
“Not only the guys here, but the guys in Japan, Europe, everywhere.”

“As I said, it’s inevitable with something like this, and it’s better to have it now than at the Buriram race or something like that.”

On the final day of running, Miller completed 32 laps and set the 17th-fastest time, finishing 1.754 seconds off the pace. He admitted he was unable to extract maximum performance from the package under those conditions, but stressed the limitation was not the bike itself.

“I wasn’t able to extract what I wanted out of the bike, but it wasn’t the bike’s fault,” Miller explained.
“It was just me. I need time on it, the same sort of bike every time I exit pit lane.”

He noted that Yamaha’s test programme had so far been heavily focused on evaluation rather than consolidation.

“We’ve been really busy swapping parts, chassis and so on,” Miller said.
“We’ve tried to understand the good, the bad and the ugly from each part over the last couple of days.”

According to Miller, Yamaha is now approaching a critical phase in its V4 development process.

“We’re at the point where we’ve got to start riding the same thing, make it very familiar, work a bit more on electronics, find some horsepower, and we’ll be alright,” he said.

From a performance standpoint, Miller’s average top speed on the final day was 327.8 km/h, approximately 10 km/h slower than the factory Ducati of Fabio di Giannantonio. However, longer-run data provided encouraging signs.

Miller was the only Yamaha rider to complete a Sprint race simulation, albeit during the morning session rather than the afternoon, as most rivals did. Notably, his opening lap of the Sprint simulation was quicker than his previous low-fuel time-attack laps.

“I was happy enough with it,” Miller said.
“I had two cracks at a time this morning, then went for the Sprint sim and went eight-tenths quicker than I did on the time attack.”

“I was really happy with the bike in the latter stages of the Sprint sim,” he added.
“Especially when the surface temperature gets hot and the bike starts moving. It stayed true to itself and did what it should do.”

Miller’s ten-lap Sprint simulation was completed 13.957 seconds slower than the best afternoon Sprint time set by Alex Marquez on the Gresini Ducati. For context, that gap would have placed Miller ninth in last October’s Sprint race at Sepang, where he finished 14th and 17.601 seconds behind on Yamaha’s former inline-four machine.

Later in the afternoon session, Miller recorded his fastest lap of the entire test, though it was only 0.010 seconds quicker than his opening Sprint simulation lap.

With Quartararo ruled out of the remaining test days due to a finger injury, Alex Rins emerged as the fastest Yamaha rider overall in 12th position, 1.178 seconds behind Alex Marquez.

Yamaha’s concession status at level D allows the manufacturer to make engine design changes if required to address unresolved issues, as well as conduct additional private testing with its race riders to compensate for lost track time.

The final MotoGP pre-season test ahead of the 2026 season will take place at Buriram on February 21–22.