Knocking from the Clock

Hi everybody, I ride VFR 800 5th Gen, red one and I am charmed!

I have the following ask: When I press the clutch handle and start to release it a strange knock is heard from the clock. Or when I hold the handle in middle position this knock is getting frequent. Sounds like a relay .. but I found nothing in the manual. Ideas?

 

Hi Bard... playing with the clutch will cause the variable air valve {or flapper valve} to open and close on top of the airbox. Sounds a bit like a ping pong ball inside the airbox.

I sometimes hear mine when slowly releasing the clutch before a green light... pop pop, rumble rumble.

Search for flapper valve for more info.

Oh and welcome to VFRWorld.

 

I hear it from the clock, not under the tank. And it happens only in gear.

I'll check this valve in the manual.

 

It's definitely the airbox intake flapper valve then.. You just provided the last piece of evidence I needed to be 100% sure.

You see, the flapper is only active while the bike if in gear. It is not actuated in neutral.

The noise sounds like it is coming from the clock because the actuator is under the tank towards the front. The noise is projected forward and reflects off of the instruments.

-Stephan

 

Ok, Thank you very much.

In the manual is written that this valve is open above 5500 rpm, and under 5000 is closed. What is my situation? Something to worry about?

 

You were right. It is airbox intake flapper. I left the tank and turn on the engine and saw the flapper.

Do I have to worry ?

 

Nothing to worry about.. all systems operating within parameters.