Question for all - Rebuilding 09 YZ450F bottom

8 replies to this topic
  • Sauberc12

Posted November 14, 2012 - 07:52 AM


Hi all, chain snapped and gashed my case, need to rebuild it. Getting the case (both sides) piston, rings, new clutch (basket maybe), top/bottom gasket kit, and the question is bearings and seals on the case. Besides the main crank bearings (2), what other bearings are needed? When I google the cases, they have several bearings on each side, but I am not sure which they are to order. Same with seals, the manual just says "seal" for all of them, no specific detail as to the name/part number etc. isn't much help, as the case pic's don't include the bearings.

Any help is apprciated

  • Geoffit

Posted November 16, 2012 - 08:13 PM


The bearing #s are in the parts list they are shown with the part they go with. I.E. the transmission bearings are with the transmission the balancer bearings with the balancer and so on. If the engine is in good shape otherwise and you are care full you can remove and reuse many of the bearings .


Posted November 17, 2012 - 02:34 AM


If it was me I would replace the bearings if your doing a rebuild

  • Kaw_04_250f

Posted November 17, 2012 - 04:40 AM


You might want to check out an aftermarket complete gasket and seal kit. I have used a Pro X before and it saved some $ over buying gaskets and seals individually. Other than the positive reviews on the website where I purchased them, that is my only experience with them.

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

Posted November 17, 2012 - 08:04 AM


You can get the Yamaha bottom end kit for $65 and it comes with all the seals and gaskets.
And if you want a good billet clutch basket you can get a performance engineering basket for $129.

Edited by trandyd, November 17, 2012 - 08:08 AM.

  • Kride

Posted December 15, 2012 - 06:53 PM


On my 2006 YZ450 F I had to replace the case halves, the biggest expense was the counter shaft bearings, OEM $55.00 each, after that I replaced all bearings, seals which I got from a local bearing house and gaskets came from Ebay. Good luck

  • srfdwg2

Posted December 16, 2012 - 11:24 AM


I have parts you need. Mint bottom end under 20 hours. Shoot me a pm.

  • FinchFan194

Posted December 16, 2012 - 04:14 PM


Would that plastic case save from TM Designworks stop a chain from breaking the clutch actuator arm?

  • grayracer513

Posted December 17, 2012 - 07:00 AM


I kind of doubt it, but if it came off gracefully enough, it might help. Better to use a real quality chain and adjust it right. People tend to run the chain tight on YZ's because they look loose when correctly set.

Related Content


The "going back to the other darkside" adventure... by Monk

Dirt Bike   Make / Model Specific   KTM   250/350/450/505 SX-F & XC-F (4-Strokes)
  • Hot  91 replies

Yamaha YZ450F 2017 by Chris.GVS

Yamaha YZ450F 2017
  • - - - - -
  • 0 reviews

2016 YZ450 by CaptainKnobby

Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  59 replies

Michigan Motocross Tires by 288yz450

Dirt Bike   Dirt Bike Regional Discussion   North
  • 1 reply

Snake pit oct 30th by The Anvil

Dirt Bike   Dirt Bike Regional Discussion   California
  • Hot  293 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.