2001? Yzf 426 stroked complete resto

63 replies to this topic
  • eatbraapdestroy

Posted February 07, 2016 - 08:37 PM


How is the bike? Any progress made?

  • Nick H

Posted April 11, 2016 - 07:02 PM


Well guys another riding season is upon us and I have decided to give this motor another shot at figuring out that tapping noise.The bike has sat in storage since last year when I gave up on the project temporarily.pulled the valve cover today and started checking everything over with a fresh mind. One of my intake valves has excessive clearance (can't remember what it was off hand will post specs tomorrow when I grab the paper I wrote them on from work) and the shim is stuck in the valve. Just read a thread in which grayracer layed out a method of tapping on the top of the valve lightly with a magnet handy.I will be trying that tomorrow. Will keep you guys posted on progress.

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  • Nick H

Posted April 15, 2016 - 08:00 PM


Well I have an update for you guys. Dropped the bike off at the local shop.they ran the bike and blew a piston.Apparently one of the intake valves was hitting the piston but I don't see any evidence of that on the valve just on the piston. I have a spare used head that I will be shipping to mongoose cylinder works on Monday to have rebuilt.amazingly the crank and cylinder came out completely unscathed. I cannot believe a valve was causing all that noise and yet the bike would start first kick.Heres some pics let me know what you guys think.ImageUploadedByThumper Talk1460779226.711330.jpg ImageUploadedByThumper Talk1460779239.246788.jpg

  • grayracer513

Posted April 17, 2016 - 07:04 AM


What exactly happened to the piston (other than the missing chunk of ring land)?  It looks to me as if it's been hitting the head squish area for a while.  If I were you, I'd double check the rod bearing clearance.


Solvent test the valves.  If any leak, pull them and chuck the stems in a lathe or even a drill and check them for being bent. 

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