Case saver failed. Clutch lever cocky smashed

5 replies to this topic
  • 288yz450

Posted October 20, 2015 - 10:47 AM


Hey guys I have a 2009 yz450. As I was practicing on my buddies private track I snapped a master link under full throttle. Case saver kind of worked but bent up and smashed into the clutch lever cock. Oil leaks now and I don't what I should do to fix it other than replace the case. I would prefer not to replace the case as I'm a cheap college student trying to make my bike last as long as I can.

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  • Goonyz400f

Posted October 20, 2015 - 11:47 AM


Weld it?

  • grayracer513

Posted October 20, 2015 - 11:49 AM


The case saver didn't fail, unless you bought one from the aftermarket that purported to be capable of such a thing.  It's a chain guide, not a case saver, and its job is to keep the top run of chain fed onto the top of the front sprocket when you're off the throttle.  


The chain will have broken for one of two reasons; either the master link was improperly installed, or the chain was too tight.  Review this post: 



As to the case, the only right way to repair that is to replace the complete pair of crankcases as a set.  The shaft bores are finished with the cases bolted together as a matched set.  You can mix them, but it's not advisable.  


Depending on the severity of the damage, which frankly doesn't look too bad, repairs might be possible also, but realize that in addition to the machined bore for the clutch release arm, a high pressure oil passage to the transmission passes through that bore.  Any welding will require re-machining the case to re-establish these features, so either way, it's gonna cost you. 

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  • 288yz450

Posted October 20, 2015 - 01:53 PM


This winter I planned on rebuilding it from the ground up besides the transmission this winter anyway. I guess more along the lines of what I'm getting at is what do you guys recommend for a short term fix. I live in Michigan so the race season ends next weekend. After that I'm tearing it all apart.

As far as short term my plan was to take release the clutch springs to free the shafts up so I can pull the clutch lever out. While apart still I was suggested to fill in the gap with an epoxy or take it to my buddies welding shop to add material back to the case enough that I can cram a seal back in it and add epoxy over the top to keep oil from spewing out. I just need another weekend out of it as of right now. If you don't think that's possible than I'm gonna hang it all up and call the season short sadly

  • grayracer513

Posted October 20, 2015 - 02:37 PM


I'm not particularly favorable to the epoxy idea because of the fact that you're dealing with oil system pressure there.  It might get your one race day in, but it doesn't take as long as you might think to blow off a quart of oil through a leak like that. 

  • Swapper265

Posted October 20, 2015 - 03:29 PM


If it were me, I'd be resigning to the fact that it's season over, albeit one week early, and fixing it properly.

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