yamaha wr 426 de comp fell out engine

3 replies to this topic
  • yamzwr426

Posted December 27, 2015 - 09:43 AM


Hi there I washed my bike today fired it up and all of a sudden it starts bogging out when letting off the throttle came home oil was coming out the engine where the de comp is, well the de comp lever was hanging out!! I don't have a lever on the handle bars as it has hot cams. Just wa Ted to know what I do next does it just slot back in and that's it ? I'll upload a photo

  • yamzwr426

Posted December 27, 2015 - 09:49 AM



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  • yamzwr426

Posted December 27, 2015 - 09:54 AM



  • grayracer513

Posted December 27, 2015 - 10:41 PM


Since you didn't get pics uploaded, I'm guessing, but on the right side of the head, just back of the decomp lever, there is a bolt either missing or extremely loose.  Be sure that gets tightened, but also be aware it's a special bolt that has a short dowel extension on the nose.  The extension fits into the groove in the lever shaft to retain it. It's an easy bolt to strip if you aren't careful to align it with the slot in the shaft.  If the bolt is missing, you'll have to get another of the correct part, or make one.  Be very sure you get the spring back on the lever, too. 


You can leave the lever out and plug the holes.  Use any bolt that fits in the shaft retainer bolt hole, and for the front, remove the radiator for access, pry the seal out, and drive in an 18mm cup plug from an auto parts house. 



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