Join Date: Jan 2013
Location: Florida in Winter; Tennessee in Summer
OTOH, there may not be a thing wrong with it. It's possible that the previous owner de-baffled the mufflers and that the noise you are hearing on deceleration is simply the typical sound that de-baffled mufflers produce on deceleration.
If it runs good on acceleration and at constant speed, and it idles good, then I tend to think there's nothing wrong with the running of the bike.
As others have suggested though, it might be a good idea to change the fluids in the bike.
My Current Rides
2009 Vulcan 900 Classic LT
2005 Harley Electra Glide Classic