title says itself. sudden strange licking/knocking/ rattling in my engine or at least when its running. revving the engine up sort of stops the sound but ive never heard this before. sounds like a piston ring is broken and flying around in there.
I had a customers bike do the very same thing today!
I added a extra head gasket to lower the compression a little & it cleared up the rattling noise about 70%. I didn't want to add a third gasket becausae I was concerned with it lowering the performance.