Piaggio Beverly 250ie 2007 noise


I just replaced the weights in my JC Costa variator; i have 20,000km on the clock and it makes a rattling sound, it made it before putting in the new weights too.

The rattling sound only happens when i am coasting, or in other words not accelerating or slowing down, it's as if something is loose in there but the mechanic said it seems to be mechanically sound, in Australia they are not too familiar with Piaggio.

Anyone else had this or similar problem and maybe knows the solution?

Thanks in advance,