Defect Investigation Detail

YAMAHA / ROAD STAR WARRIOR / 2003

Components - Details
NHTSA Action Number: PE03038 Vehicale/Equipment Name: YAMAHA
Vehicale/Equipment Model: ROAD STAR WARRIOR Vehicale/Equipment Year: 2003
Component Name: POWER TRAIN:MANUAL TRANSMISSION Manufacturer's Name: Yamaha Motor Corporation, USA
Date Opened: Aug, 11 2003 Date Closed: Nov, 06 2003
Subject: UNINTENDED REAR WHEEL LOCKUP Summary: 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.