Scratchy tapping noise during engine braking

[yuckhil]

For the past few hundred km now, I hear this tapping noise whenever I roll off the throttle with the clutch engaged.  To describe, it sounds like a free bolt hitting a numberplate - regular (tap tap tap), metallic and scratchy.  I also hear a single tap sometimes when I shift up into 3rd gear.  Any idea what this could be?  Thanks.

I usually don't use engine braking, especially not down through the gears.  However, I often roll off the throttle a bit, e.g. riding down slopes, through turns, etc.  I hear the noise only during the deceleration and not thereafter.  I've started pulling in the clutch lever to coax her through to the 36,000 km service.

[pmackie]

Check your chain for wear and adjustment. On decell, the top of the chain is free to slap, and may be contacting something.

[yuckhil]

Wow, you're good!  That fixed it.

Huge relief that it wasn't something broken in the transmission!