What was the problem with the 2003 Yamaha WR450?
Yamaha fixed the problem with the introduction of the 2004 WR450F. They changed the design of the idler gear assy and incorporated a free wheeling feature that allowed the force from a backfire to spin the idler gear backwards without engaging the starter motor gear.
Is the 2003 WR450F gear cover flat?
The 2003 original gear cover is flat, the 2004 and newer WR450F has a chamfered bulge in the cover to accommodate the longer axle on the updated gear assy. The starter motors for 2003, 2004, and 2005 all have the same part number, don’t know about 2006, so they are all identical. The starter was never the cause of the sheared woodruff key probem.
Are there any problems with the WR450F starter?
The starter on the WR450F does have its little problems though. The starters don’t spin the engine fast enough when the weather is cold and often you have to kick start the bike the first thing in the morning, after that the bike starts on the electric starter without any problem. Jetting may contribute to this situation.
How to tell if a WR450F has an updated torque limiter?
You can tell if a WR450F has the updated Torque Limiter Assy by looking at the cover over the idler gear. The 2003 original gear cover is flat, the 2004 and newer WR450F has a chamfered bulge in the cover to accommodate the longer axle on the updated gear assy.
Yamaha fixed the problem with the introduction of the 2004 WR450F. They changed the design of the idler gear assy and incorporated a free wheeling feature that allowed the force from a backfire to spin the idler gear backwards without engaging the starter motor gear.
The 2003 original gear cover is flat, the 2004 and newer WR450F has a chamfered bulge in the cover to accommodate the longer axle on the updated gear assy. The starter motors for 2003, 2004, and 2005 all have the same part number, don’t know about 2006, so they are all identical. The starter was never the cause of the sheared woodruff key probem.
The starter on the WR450F does have its little problems though. The starters don’t spin the engine fast enough when the weather is cold and often you have to kick start the bike the first thing in the morning, after that the bike starts on the electric starter without any problem. Jetting may contribute to this situation.
You can tell if a WR450F has the updated Torque Limiter Assy by looking at the cover over the idler gear. The 2003 original gear cover is flat, the 2004 and newer WR450F has a chamfered bulge in the cover to accommodate the longer axle on the updated gear assy.