siezed 450f

5 replies to this topic
  • hondanut147

Posted December 29, 2011 - 01:34 PM


I am putting in a piston in a 06 450, and when i pulled the cams out, the cups for the shims are busted and jammed down in there slots.... just wandering if anyone has run into the same delemma?? How i should proceed with this.. I normally work on hondas, and have never seen this, so any advise would be greatly appreciated..

  • 2grimjim

Posted December 29, 2011 - 03:14 PM


Piston contacted the valves. Could be caused by broken or worn camchain, or overreving. Probably looking at a new head. Generally caused by lack of proper maintainence or abuse.

Not something seen very often on Yamahas.

  • hondanut147

Posted December 29, 2011 - 03:35 PM


YA im working on this for a friend he didnt let it warm up before i was thinking cold seize... Also i only drained bout half cup of anti freeze out of it... i was also thinking it came in contact with the piston though. a violent enough of a seize with it tdc could do that...

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  • grayracer513

Posted December 29, 2011 - 04:59 PM


Contact Engine Dynamics about a repair. You'd be surprised what they can fix and what they charge for it.

  • hondanut147

Posted December 30, 2011 - 11:28 AM


Got permission to dig deeper into the bike after i discovered the vavles were stuck open.. Took the head off then the cyclinder and discover a whole heap of shit. The piston shattered off the rod. Fragments all over the place down in the case and the rod snaped and went into the cylinder wall cracked it open. The head looks good so far gonna take it into the local dealership and find out for sure and make sure it isnt warped or anything but thanks for the help fellers....

  • hondanut147

Posted January 02, 2012 - 11:01 AM


looking for a complete motor for this bike 2006-2009.. he wants to fix it so also will be willing to look for a head that is in good shape so could rebuild if anyone knows where to find part please let me know

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