The National Highway Traffic Safety Administration has officially announced the recall on 2015 Yamaha YZF-R1 and YZF-R1M models to correct a problem with their transmissions. As we previously reported, the issue may cause the second, third and fourth gears to break under excessive stress. The recall affects 2,921 motorcycles in the U.S.
From a letter Yamaha released, we know the second gear wheel and pinion gears may break when put under high stress or from improper shifting because of inadequate component strength and stress concentration at the gear teeth bottom land. Meanwhile, the third and fourth wheel gears may deform or break under hard use due to inadequate component strength. Should any of these gears fail, the transmission could lock up, causing a loss of control and increasing the risk of a crash.
New documents released by NHTSA reveal Yamaha Motor Co. alerted its U.S. subsidiary about the problem on Nov. 13 after it was discovered during quality control testing. To correct the problem, Yamaha designed new gears with a different shape, size and material to improve durability. The new component was introduced to 2016 R1 and R1M models but dealers will need to replace the transmissions on all 2015 units. The process is quite complicated, requiring about 16 hours of work.