Oil pump primary drive gear keeps snapping pictures included HELP

1 reply to this topic
  • cartwrna

Posted October 16, 2011 - 12:33 PM


I own a 2005 yz450F. While riding the other day it locked up the back tire and just died out of the blue. I tore into it and found that the oil pump primary gear had snapped in half came off and was all tangled up in everything. Upon falling off it left alot of metal flakings and cut into the case some. The preious owner said that the same thing had happened in the past and he had fixed it once already. Dont know why the gear would do it again and need help finding out why. I dont know if it was an installation mistake or what. If someone could help that would be great. Also can I just file down the metal shavings where it cut into the case and be okay as long as nothing can touch it? I will add the pictures in one minute.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • grayracer513

Posted October 16, 2011 - 01:04 PM


The oil pump gear is driven by the pump idler gear, which is driven by the kick starter gear on the back of the primary driven gear assembly (clutch basket). If this is a repeat failure, it's probable that the idler gear is damaged, having a malformed tooth that's breaking pump gears. There are a total of 5 gears in that train that mesh together, and they should all be checked.

Related Content


Should I buy this bike? help....... by Numsa Hul

Dirt Bike   General Dirt Bike Forums   What bike should I buy?
  • * * * * *
  • 10 replies

James Stewart back on a YZ450F by YamaLink

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies

05 yz450f not fast enough by RedeyeYZ

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • Hot  38 replies
WR Camshaft Swap Info - last post by jamesm113

WR Camshaft Swap Info

  • 0 replies

BIGBORE FOR YZ450F 2006? by Taattie94

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 5 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.