Strange Noise (w/clutch engaged, transmission in gear)

There is a strange clicking/gurgling noise, relative to a coffee maker gurgle, but edgier. It is directly related to the clutch fluid as far as I can tell.

The noise only occurs when the clutch lever is pulled in and the trans is in gear. When squeezing the lever in more, the sound increases/starts, then goes away if held in place.

I assume I need to flush the clutch reservoir again. Has anyone else experienced this?

Thanks in advance!

 

This might just be the flapper valve solenoid; when the clutch switch gets a little dirty and makes intermittent contact, the solenoid can make electrical buzzing sounds from beneath the fuel tank. Try pulling the clutch switch wires off and see if the sound goes away. If it does then you could try spraying electrical contact cleaner into the switch.