I was helping my cousin with a motorcycle teardown a while back (planning for a café racer build) and was puzzled by something on his '07 Karizma.
The red arrow in the picture above points to a hollow plastic container with a single opening that twists into a hole on the air intake piping.
I'm puzzled as to why Hero Honda went to the trouble of attaching this extra component to the motorcycle. It looks like the effective volume of the intake is increased as a result of this component.
Does it have any impact on the motorcycle's performance ? My hunch is it has something to do with increasing the effective pressure at the engine inlet but can't be sure.