Yamaha has unveiled its much-anticipated V4-engined M1 MotoGP bike ahead of its competitive debut in the hands of test rider Augusto Fernandez at the San Marino Grand Prix this weekend.
The bike - unveiled with, unsurprisingly, wildly different aero to what is currently being run on the inline-four M1s - is widely expected to form the basis of what the factory team and satellite team Pramac take into battle next year, the final season of MotoGP's current regulations cycle.
It retains the YZR-M1 nomenclature as it stands, despite the change in engine configuration.
Here's everything you need to know about a significant moment for Yamaha, which also marks the end of an era in MotoGP.
How it got to this
Yamaha pivoted to inline-four engines with the debut of the four-stroke MotoGP regulations in 2002, and over the first two decades the inline-four-engined M1 bikes had always proven at least baseline competitive - propelling the likes of Valentino Rossi, Jorge Lorenzo and Fabio Quartararo to titles.
In the current manufacturer landscape, under the 990cc rules introduced in 2012, the Yamaha's reputation crystallised as that of a peak power-limited bike that will never dominate the speed traps - especially as Ducati's V4 and then KTM's V4 made it their forte - but will make up all the lost laptime and then some in superior cornering ability, while also being the most rider-friendly bike on the grid with which even a rookie could thrive immediately.
But a dramatic decline in competitiveness - one that first denied Quartararo a second title that had looked nailed-on in 2022, then relegated all the Yamaha riders to effectively also-rans in 2023 - prompted a push for drastic alternate solutions, one that eventually led to the development, and now the upcoming competitive debut, of Yamaha's V4 990cc bike.
The development process
In response to media reporting during 2024, Yamaha finally acquiesced and confirmed a V4 project was in parallel development with the current inline-four bike in September of that year.
Luca Marmorini, a former Ferrari Formula 1 engine chief, had been brought in as a consultant and was reported to have steered Yamaha this way - and during the 2025 season it began track testing the engine with a barebones placeholder chassis around it.
The bike has since developed, with testing duties carried out by new test team additions Augusto Fernandez and Andrea Dovizioso - who have superseded previous designated tester Cal Crutchlow after a lingering had injury kept the three-time MotoGP race winner on the sidelines for almost all of 2024.
Quartararo, Alex Rins and Jack Miller all sampled the bike for the first time last Monday in private testing at Barcelona, which was rain-disrupted.
MotoGP engine specifications are frozen through 2026, meaning by default manufacturers cannot introduce significant changes or performance upgrades in next year's spec relative to this year's.
However, Yamaha remains a Rank D MotoGP manufacturer under the current concession system. Only Rank D manufacturers are unbound by the engine freeze, and Yamaha has no immediate prospects of moving up to Rank C.
Yamaha has not committed to racing the V4 bike at the expense of the M1 in 2026, insisting publicly that the more competitive of the two bikes would be the chosen one. It reiterated this at Misano, where Yamaha managing director Paolo Pavesio insisted a decision could only be taken after a competitive debut.
However, the full-tilt change away from the inline-four in 2026 has been openly treated as both the stated aim and increasingly an inevitability by riders.
What it's supposed to fix
In theory, laptime is laptime, and even if the inline-four configuration is by pure physics less conducive to delivering straightline speed and more conducive to cornering, that shouldn't matter as long as the end result is competitive on the stopwatch.
But while that hasn't been the case for M1 since 2022, its riders have also grown more and more irritated through their perception that the inline-four left them unable to race other bikes - which, following Suzuki's withdrawal of its factory team (and its inline-four engine) at the end of 2022, are now all V4-engined.
Quartararo has lamented over and over again how the M1 would not allow him to punch out of slow corners well enough to set up a move under braking, nor even utilise the slipstream to pounce at the end of a long straight. He has also felt he's often unable to run his preferred lines through the corner because the V4 bike ahead of him will scrub off much more speed while blocking the corner, but then accelerate much better from the low speed.
Quartararo has not been alone in being frustrated with these dynamics - though he has been the most vocal about it.
The longer-term implications
The Yamaha V4 is a crucial trial run ahead of the 2027 rules reset, which each of Ducati's MotoGP rivals hopes will finally dent its current premier-class dominance.
The switch to 850cc designs means a new engine will have to be used, but it is widely expected that every manufacturer will race a V4 engine.
This is because breaking away from the trend for an inline-four design has been further disincentivised by the change to the aero rules: front aero will be required to be more compact in height and width, and as measurements are not taken relative to the edges of the bike design but are absolute in values, the wider inline-four is made more aero-restrictive, which no manufacturer wants to accept.
So while the current V4 project can only pay off directly in 2026, a season for which it would feel fanciful for Yamaha to target unseating Ducati, it is a crucial runway for the following year - and for convincing Quartararo to stick with Yamaha over other manufacturers with a lot more experience of exploiting and bettering V4 MotoGP engine designs.
The Misano expectations
The riders who tried the V4 in a private test after Barcelona were all barred from discussing the test on Thursday - with a request from Yamaha not to ask about it - while Fernandez was not put up in front of the media for a session like he normally is when making a wildcard appearance.
However, there were hints here and there that the test had been positive, in particular Rins's slightly roundabout suggestion that from what he saw of Fernandez testing the bike it "looks great!", and even floating the idea of Fernandez being a competitive threat this weekend.
"It would be, like, crazy - in a good sense of the word," if Fernandez beat some of the inline-four Yamahas, Rins claimed.
A lot of things to say, but a lot of things I can’t tell 🤐🤭 #PlanV #Yamaha #MotoGP #SanMarinoGP pic.twitter.com/cXKZcITOyW
— Alex Rins (@Rins42) September 11, 2025
But what is also clear is that the bike will not be campaigned by Yamaha regulars before the end of the season. While in theory the regulations would permit such a switch under Yamaha's Rank D status, the fact all the relevant riders have already used up their aero homologations for the year makes it a non-starter.
"It ain't happening. There's that [the aero homologations] and other parts. There's no chance," Miller said.
