Unintended rear wheel lockup

An NHTSA Preliminary Evaluation into Yamaha vehicles. Closed 6 November 2003.

Investigation
PE03038
Type
Preliminary Evaluation
Opened
11 August 2003
Closed
6 November 2003

What NHTSA investigated

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 yamaha?s recall, we are closing this investigation but will continue to monitor the field performance of all road star model motorcycles to assess the performance of those bikes not covered by the recall.should the facts warrant additional investigation, we will proceed accordingly.

Recalls that followed

  1. Yamaha — Power Train: Manual Transmission06V39700017 October 200620,000 vehicles
  2. Yamaha — Power Train: Manual Transmission03V30900026 August 200329,139 vehicles

Vehicles covered

MakeModelModel years
YamahaROAD STAR1999–2003
YamahaROAD STAR WARRIOR2002–2003

Source

From NHTSA’s investigation file, rebuilt daily. To report a problem with your own vehicle, go to nhtsa.gov/report-a-safety-problem. All open investigations.