that annoying rattle

[tmykool2]

the metal tubing from the oil sending unit is tapping the motor bc the O ring has disinegrated or out of position, gets louder when down shifting.

 

[one2dmax]

What? Any pictures when you open it up would be handy. This is a new one.

 

[tmykool2]

 

[MaxMidnight]

The only issue I have read of is with displaced orange 'O' rings but never that they cause an audible rattle.
As they are inside the crankcase I'm surprised that you would hear any rattle emanating from there.

Are you sure that it isn't coming from the front header due to the inner and outer tubes separating?

 

[one2dmax]

I am still not seeing the issue? If the oring is displaced or gone then it won't hold solid in place. Your picture shows it has been removed or at least not bolted in place currently.