Everyone shocked by yet another Yamaha V4 engine test. New non-working spare part makes Quartararo Brutal talk and go away.

The Valencia circuit, still humming from the echoes of the 2025 MotoGP finale, became the stage for yet another chapter in Yamaha’s turbulent V4 engine saga on November 28, 2025.

As the post-season test wrapped up its second day, whispers turned to outright shock when Fabio Quartararo, Yamaha’s beleaguered star, abruptly halted his session.

A faulty non-working spare part—rumored to be a critical crankshaft component—forced the 2021 world champion to park his bike and unleash a torrent of frustration that left the paddock reeling.

Eyewitnesses described the scene as tense from the outset. Quartararo had clocked a respectable 1:29.927 in the morning session, placing him 15th overall and just 0.554 seconds off Raul Fernandez’s benchmark. But as engineers scrambled to swap the offending part, the Frenchman’s patience snapped.

“This is unacceptable,” he reportedly snapped over team radio, his voice cutting through the static like a revving Desmosedici. By midday, he was done—not just for the day, but signaling a deeper rift with the Iwata squad.

The incident wasn’t isolated; it capped a series of disheartening V4 outings that have plagued Yamaha since their prototype debut in Barcelona back in September.

What began as a bold pivot from the outdated inline-four configuration—Yamaha’s stubborn holdout against the V4 dominance of Ducati, Aprilia, KTM, and Honda—has devolved into a parade of reliability gremlins and underwhelming performance.

The “non-working spare part” wasn’t just a mechanical hiccup; it symbolized Yamaha’s broader struggle to catch up in a grid where rivals have honed V4 tech for years.

Quartararo’s “brutal talk” didn’t mince words. In a hasty debrief with select media, the 26-year-old didn’t hold back: “We’re missing quite a lot—power delivery, rear grip, electronics.

And now this? A spare that doesn’t even function? It’s like they’re testing us more than the bike.” His candor, laced with exhaustion, echoed sentiments from earlier tests.

At Misano in mid-September, he was outright negative, calling the prototype “aggressive” and lacking the front-end confidence that defined his 2021 title run. Valencia offered glimmers—better braking stability, per teammate Alex Rins—but the spare part fiasco extinguished any optimism.

The paddock buzzed with speculation. Jack Miller, the veteran Aussie riding for Yamaha’s satellite Pramac team, tried to stem the tide, praising Quartararo’s morning laps as “impressive with limited power.” Yet even he admitted the V4’s electronics needed a complete overhaul.

Sources close to the team revealed the spare part issue stemmed from rushed prototyping: the crankshaft, essential for balancing the V4’s 90-degree cylinder bank, failed under simulated race loads, overheating and seizing after just 15 laps.

No backup was ready, stranding Quartararo mid-session and forcing a red-flag interlude that delayed the entire test by two hours.

Social media erupted, amplifying the shockwaves. On X, #YamahaV4Fail trended globally within minutes, with fans posting helmet-cam clips of Quartararo’s aborted run.

One viral thread from @crash_motogp read: “Yamaha’s new V4 must prove itself to Fabio at Sepang—Valencia just proved it won’t.” Replies poured in, blending sympathy for El Diablo with calls for his exit: “Time to jump ship to Aprilia or Ducati.

Yamaha’s killing his career.” Paddock insiders noted Quartararo’s post-test huddle with manager Eric Escoffier, fueling rumors of a 2026 contract clause allowing an early out if the V4 doesn’t podium by round three.

This isn’t Quartararo’s first rodeo with disappointment. His 2025 season was a grind: sixth in the standings with 50 points, a lone podium at Jerez, and consistent midfield battles against a Yamaha M1 that felt like pushing a relic.

The V4 switch, announced in April, was meant to be salvation—a “pivotal” move, as Quartararo himself urged, to match the V4’s superior torque and acceleration. Early European testing at Valencia in April showed promise, with test rider Augusto Fernandez logging clean laps.

But real-world application has been a nightmare: Barcelona’s private shakedown revealed chassis mismatches, Misano exposed grip deficits, and now Valencia’s spare part debacle has everyone questioning timelines.

Engineers at Yamaha Motor Racing are under siege. Massimo Meregalli, the team director, issued a measured statement: “We’re addressing the reliability issues head-on. The V4 has potential, but integration with the chassis and aero is complex.” Behind closed doors, the pressure mounts.

With homologation deadlines looming for 2026, every failed part risks concessions—extra testing days, but at the cost of development secrecy. Rivals like Ducati, fresh off Marc Marquez’s title charge, are already mocking the stumbles, with Gigi Dall’Igna quipping, “Yamaha’s V4? More like V-zero progress.”

Quartararo’s decision to “go away”—skipping the private Yamaha test day on November 29 and heading straight to offseason training in France—sends a clear message. “Sepang will be super important,” he told Crash.net en route to the airport.

The February 2026 winter tests in Malaysia loom as judgment day: if the V4 doesn’t deliver a top-five qualifying, whispers of a Ducati or Aprilia switch could turn to shouts. His manager has already fielded calls from multiple teams, per reports from Paddock GP.

The broader implications for MotoGP are seismic. Yamaha’s inline-four loyalty once defined innovation—lightweight, rev-happy engines that won eight titles from 2004-2015. But in the aero-dominated, concession-fueled era, it’s a relic. The V4 shift, while necessary, exposes Yamaha’s lag: they’re playing catch-up while Ducati iterates on year-five V4 refinements.

Fans and analysts alike are shocked not just by the test failure, but by how it humanizes Quartararo—a rider who’s sacrificed prime years for loyalty, only to face mechanical betrayal.

Yet, glimmers of hope persist. Rins, ever the optimist, noted “slight improvements” in Valencia, particularly in corner entry. Miller, eyeing a potential V4 wildcard at Motegi, volunteered to “forfeit results” for data gathering—a nod to his experience on Ducati’s V4 platform.

And Quartararo? His brutal honesty might just light the fire Yamaha needs. “Pain builds character,” he posted cryptically on Instagram, a photo of his scarred leathers captioned #NeverGiveUp.

As the off-season dawns, the shock lingers. Another V4 test, another setback— but perhaps this one’s the catalyst. Quartararo’s walkout isn’t defeat; it’s a demand for revolution. In a championship where engines win wars, Yamaha must deliver.

Sepang awaits, and with it, the verdict on whether El Diablo stays or flies. The grid holds its breath; the comeback—or collapse—starts now.