Yz426 piston seized?Please help

42 replies to this topic
  • grayracer513

Posted May 07, 2013 - 10:16 AM


If you replace the rod, you need to replace the bearing. It is also considered unwise to reuse the crank pin, but you could if it's in excellent condition.

But the thing is that you will then be buying a bottom end, dismantling it, and paying to rebuild the crank. That doesn't seem to me to be a good idea when you could as easily rebuild your own and still have a pure 426 for the same price, less what you would have spent on the 400 bottom end.

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  • NitrousR1

Posted May 11, 2013 - 05:56 AM


I would stay away from that 400 bottom end. Chances are theres a problem with it. You'd be spending $10 to save $1. I would get a new crankshaft, OEM Wiseco or Hotrods. You are taking a chance having your used 426 crank rebuild. There are plenty of good shops who can rebuild it, but your taking a chance. If you go that route replace the bearing and rod. Bottom ends get expensive but money spent here is necessary.

  • mpmoto

Posted May 11, 2013 - 06:37 AM


post up a pic of the cam journals and the journals in the head.

if those ccaps were loose I'd almost guarantee that it has cause damaged to the head. if the journals are scored badly from being loose then it will bind up

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