Topic: 750 K7 Fuel tank - lid vibration (resonance)

[Erny]

I noticed during test ride that lid on tank is making strong annoying noice - vibrating within some RPM.
I was looking under it and it is obvious, there is metal-to-metal and it simply makes that noise. Did not at first view that something is missing there.

Just now I opened spare parts catalogue and I see there some O ring (position 23 on attached pic) that is not on my bike.
But I did not find place where it could be installed - can someone advice?

Thinking about to wrap it around item 19? This could explain shape displayed in SPC.

Here are also pics from my lid.

[Stev-o]

Try adjusting the spring up, part #16 on your fiche.

[madmtnmotors]

LOL! I have the same issue with my K8's and F2's. I have never found the o-ring shown in the parts fiche on any of the K7/K8 or F2 tanks I've laid hands on and for the life of me can not figure out where it would go. "Item 19" you refer to is the clip that holds the latch to the lid and I don't see where that would relieve anything. If you figure it out be sure to let us know!

As Steve mentioned, I too have had some limited success by bending the spring (item 16) up a little so that it exerts more pressure on the lid in the closed position.

[Erny]

If O-ring is shown there it must be there not? 

Hope someone else will comment/advice

[madmtnmotors]

Hope someone else will comment/advice

I hope so to. Between the six CB750 K8's, one CB750 F0, three CB750 F2's, and four more K7/K8/A2 fuel tanks I've laid hands on, none of them have had any kind of o-ring anywhere under the fuel door, and I have yet to find anybody that can explain where it might supposed to be. 

[Desert-SOHC]

My K8 used to resonate, but I got it to stop by adjusting (bending)the springs #16 & #5.  16 needs to put enough pressure on the door to stop the vibration.  I have to push the door down a bit to get it open, but its quite.