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Discussion Starter · #1 ·
This started with bike backfire when starting and has not ran since. After checking everything I could brought bike to Honda they told me internal engine problem out of timing. I tore engine down found cam chain and tensioner in perfect condition. When i try to line up T mark with piston at tdc it does not line up. piston is at bottom of stroke. Does this mean crank damage. Honda told me they could not quote for repair with out removing head to determine what repairs needed. If crank would need replacing total rebuild approx cost $3000. bike is 2007 rancher 420 any advice would be appreciated.
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Post some pictures and show we're the mark is on tdc compression stroke might need to rotate it 360 deg


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You are not going to believe this happened. Seriously. I repaired my neighbor's 2008 420 with the same symptoms as yours but the gear on his camshaft spun a little over 90 degrees out of timing. I have no idea how or why this happened but it bent a valve doing it.

And the ONLY THING that saved me from bending another valve after it all got put back together was that I DID NOT HIT THE STARTER BUTTON. I hand cranked the motor through and it would not make it all the way through a complete rotation. This then started the hunt for why and discovery of the spun gear on the camshaft. At that point, we bought a new camshaft from Honda rather than try to spin that gear back into proper timing.

See . . . I told you it would be unbelievable.

Rick
 
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Discussion Starter · #5 ·
I found woodruff key sheared that hold flywheel in place on crank shaft. do not understand how or what would cause this. Have not pulled valves out of head. I don't see any marks on piston or valves. How did you determine your gear moved on the cam shaft.
 
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