New standards will apply to the leathers which MotoGP riders wear next year, after multiple instances of unzipping while on-track.

Fabio Quartararo was issued a three-second penalty after last year’s Catalan Grand Prix when he finished the race with his leathers open and had tossed away his chest protector.

He revealed at a later round that Alpinestars had subsequently bolstered the velcro fastenings, notwithstanding that its initial investigation is said to have found that what the Monster Energy Yamaha rider wore in the Catalunya race was “in normal working order”.

However, Quartararo’s leathers came open again at Aragon in the most recent September, when he shunted Marc Marquez after the Repsol Honda pilot’s error on the opening lap around the MotorLand.

Alpinestars would explain to media that a combination of factors, including the deployment of the airbag (consistent with design), friction from the track surface, and then being struck by his own bike, caused the teeth on the Frenchman’s zipper to fail.

A new rule has now been agreed by the Grand Prix Commission (GPC), following its meeting at the Valencia MotoGP round.

“Following incidents where riders’ leathers have become unzipped whilst on track, a new system of positive fastening has been agreed with the manufacturers,” the GPC advised.

“Use of leathers with this closing system is henceforth mandatory.”

That is one of several technical regulations which have taken effect for the 2023 season (including, technically, the post-season test held two days after the 2022 finale at Valencia’s Circuit Ricardo Tormo).

Fuel tank capacity for the new sprint races has been confirmed as 12 litres, although teams have the options of a purpose-built tank or “an alternative method of reducing capacity in the formal tank.”

Swingarm spoon ground clearance has been raised from 15mm to 35mm after a bike broke one on a kerb at this year’s San Marino Grand Prix.

Rules around materials for brake disc carriers and fuel tanks have also been confirmed.