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Nc700s whirring noise/cam chain tensioner query

Iyotanka

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Hi my nc700s has a strange whirring noise on load and deceleration (even in neutral). I've checked the valves (3 were slightly out of spec but tight not loose). After reading through the forums I've checked the cam chain and the tensioner, chain has no slack and the tensioner appears to be fine however the only thing I can't confirm is if its out of service spec.

The service manual says the wedge should only rise 6 mm however the wedge is out about 18-20mm from the top of the tensioner but there's also a black depressable wedge next to the metal wedge and the gap in height between the two wedges is under 6mm. Where am I supposed to be measuring from and which wedge is the one I measure as my manual doesn't show the same tensioner top (single wedge at the top mine appears to have 2)

The tensioner appears to be pushing the chain quite a bit that it's not an oval but more a crescent shape now which has me concerned that the chain is near limit too but want to confirm before I replace it all.

Anybody with detailed pictures/knowledge of where I'm supposed to be measuring from please advise
 
My limited understanding is that happens if you rotate the engine backwards (Clockwise= BAD!!). If it's truly broken I believe you'd hear some chain slap when the engine's decelerating. Here's a couple threads on it:

Looks like I'll go first -dammit
Cam Chain Tensioner Failure

Edit- Here's a service Manual's drawing of what you should be seeing:

Cam chain Tensioner.jpg
 
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My limited understanding is that happens if you rotate the engine backwards (Clockwise= BAD!!).

Not if you're rotating it by hand, because the force on the cam chain & tensioner is proportional to the speed of rotation. Rotating the engine when adjusting valves is much easier to do after removing sparkplugs, since you're not fighting compression. This also has the advantage of putting very little tension on the cam chain and making it easier to jog the engine to TDC.
 
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