rattling noise off throttle???

[spkrboxx]

I have a 2001 honda elite S, right now it has;
Taiwan 50mm kit
V8 pipe
stock carb with new jet

I am getting a higher frequency rattle from what sounds like the fan side of the motor when I come off the throttle and am slowing down.
Any ideas? The only thing strange with the scoot I found since I bought it was the lower piston ring was missing when I pulled the jug off. But I am not sure if the stock bore had a ring there, and I never found any pieces of it.

[indetrucks]

Sounds like piston slap to me...

If the piston has a spot for a lower ring and it isn't there, I would stick one on.
Some run one ring as they feel it will produce more power (less friction). But you can run the risk of excessive wear on the one ring.

Does it sound like this?
Go to :45 seconds in
http://www.youtube.com/watch?v=nofjqxJgjvM

Even my gutless Spree has two rings.