Yamaha has finally issued official recall notifications to owners of 2015 R1 and R1M superbikes. The recall was issued over concerns of potential gearbox failure, leading to locking-up of the gears and causing a potentially fatal crash.

The notice states both second gear wheel and pinion gears in the transmission may break as a result of extremely high stress and improper shifting due to inadequate component strength and stress concentration at the gear teeth bottom land. In addition, the third and fourth wheel gears may be deformed or break as a result of excessive stress caused by hard usage.

Models affected are the 2015 YZF-R1, YFZ-R1C, YZF-R1MF, and YZF-R1MFC, and Yamaha is not allowed to sell any 2015 R1s in the US till affected bikes are rectified. The procedure calls for engine removal and the gearbox split apart to replace the main axle shaft.

Yamaha said the procedure will take an estimated 16 hours, and has denied that owners affected by the recall will have their bike’s engine replaced, or be given a new replacement motorcycle. 2016 R1s are not affected by this recall.