MotoGP engine list: Who used what during the 2021 season

Fortunately, there was no such drama for any of the manufacturers during the 2021 campaign, which saw a near-normal 18 rounds (albeit with repeat visits to four circuits) after the Covid reduced 14-rounds the previous year.

That also meant engine use returned to the usual seven changes per rider limit (rather than five in 2020) with up to nine changes - and design modifications - allowed for concession manufacturer Aprilia.

Unlike in 2020, where Yamaha's Maverick Vinales received a pit lane start at Valencia for needing an extra (sixth) engine, all manufacturers completed this season within the specified limits.

Repsol Honda were the only non-concession team not to run all 7 engines available, opening 6, but neither bike took part in the Valencia race due to injuries for Marc Marquez (who withdrew before the event and was not replaced) and then Pol Espargaro (absent after Friday practice).

Aprilia used 8 out of 9 engines available for the bike of Lorenzo Savadori and Maverick Vinales, but the machine missed three events due to injuries for Savadori (Austria/Silverstone) and then Vinales' COTA withdraw.

Riders with the most engines withdrawn this season were Johann Zarco (Pramac Ducati), Takaaki Nakagami (Honda), Miguel Oliveira (KTM) and Aleix Espargaro (Aprilia), who all 'lost' three engines.

Having engines withdrawn is only really a concern if it occurs well before the engine reaches its planned milage limit, or signals an inherent design fault that could also spell trouble for other engines.

The first riders to lose engines during the 2021 campaign were Alex Rins (Suzuki) and Franco Morbidelli (Petronas Yamaha), both in Germany, round 8.

Morbidelli's A-spec bike didn't lose another engine for the rest of the season as it was passed to Garrett Gerloff, Cal Crutchlow, Jake Dixon and finally Andrea Dovizioso.

But the situation looked more serious for Rins after he lost two engines during the course of the Sachsenring weekend.

One of those engines had seen plenty of action, being introduced in Qatar and enduring race accidents at Portimao, Jerez and Le Mans before a terminal issue on the main straight during FP3 in Germany.

However the other was only introduced at Mugello (round 6) and took part in just five track sessions before being withdrawn due to an unspecified technical issue, said to be related to a fault outside of the engine itself.

Rather than Suzuki opening new powerplants to compensate, Rins reverted to engines 1 and 2 (with which he began the season) for the German race and following Assen weekend.

Fortuantely experiencing no further engine issues, Rins then joined team-mate Joan Mir in opening engine '5' after the summer break in Styria.

The Avintia Ducati entry of Enea Bastianini, Monster Yamaha of Maverick Vinales/Cal Crutchlow/Franco Morbidelli and Petronas Yamaha of Valentino Rossi completed the season without having any engines withdrawn.

** Jorge Martin's Pramac Ducati was also used by Tito Rabat and Michele Pirro, while he was injured.

** The Factory-spec Monster Yamaha that Morbidelli finished the season with was previously used by Maverick Vinales and Cal Crutchlow. The bike did not participate in the Austrian GP.

** The A-Spec Petronas Yamaha that Dovizioso finished the season with was previously used by Morbidelli, Garrett Gerloff, Crutchlow and Jake Dixon.

** Alex Rins' Suzuki was not used in Catalunya, after his pre-event injury.

** The Repsol Honda of Marc Marquez was also used by test rider Stefan Bradl, while he was injured. Marquez's bike was not used at the Valencia finale, when team-mate Pol Espargaro also missed the race (and was not replaced) due to injury.

** The Aprilia RS-GP that Vinales finished the season with was previously used by Lorenzo Savadori. The bike was not used in Austria, Silverstone and COTA.