New here, anyways I just put a new front sprocket (-1) and rear sprocket (+1) along with a new chain on the bike. Now when I cruise at about 6000rpm (in 3rd gear for example), I get this awful rubbing noise from the from sprocket area only when I engage the clutch lever and coast. I don't do this very often, but it gets really annoying when I am shifting down slowly.

Any ideas?

I didn't notice the problem before but then again my chain was horribly worn out which was most likely louder.

I might need to take a video.

 

I should also mention is sounds like constant chain on plastic.