UNINTENDED REAR WHEEL LOCKUP

What NHTSA is examining

Summary: on august 22, 2003 yamaha notified the agency that it was recalling certain model year2001 xv1600 ?road star? Model motorcycles to address transmission failure in those vehicles.according to the company, the transmission would fail due to excessive bushing wear on the 4th pinion gear.based on its analysis of failed transmissions from the field, the company found ?uneven contact between the engagement dogs on the 2nd/3rd pinion gear.when in 4th gear, these uneven surfaces caused uneven bushing wear in the 4th gear bushing.this wear would eventually cause the 4th gear retaining circlip to fail, leading to transmission failure.?this could result in both transmission and rear wheel lockup and yamaha concluded a safety recall should be conducted to address the problem.yamaha is limiting the recall?s scope to those motorcycles built between november 30, 2000 and january 24, 2001 based upon the following:1. Yamaha u.s. Reported field failures (involving bikes built in december, 2000) to yamaha japan.2.yamaha japan investigated and validated the cause described above.3.yamaha japan identified the problem was related to the engagement dog on the 2nd/3rd pinion gear.4. Yamaha japan records indicated that the jig used to produce the 2nd/3rd pinion gear was re-calibrated on january 13, 2001.5.parts produced before november 30,2000 and after january 13, 2001 were sampled and found to be within specification (the recall was extended beyond january 13 build as a precaution).with…

Vehicles under investigation