I have a 07 deluxe with loud snaping / clatter on decel. Also ran leaner and hotter each time noise would appear. Drivabillity was deteriating yet intermitant.some times turning off the ignition and back on would make it reset and run better - some times worse. Found the noise was the fuel injectors were being hammerd by improper signal from ecm. Replaced ecm and runs great and no more noise!

 

It might be your shift linkage rattling. Bike runs great otherwise right?

I get the same thing on my RKC. It was so bad yesterday I thought I might have to do something about it but today it's hardly clattering at all.

 

Hi I think its worth checking the electronic controle module. My bike did the same (a hit and miss at the start) but as the the miles added up on the bike, the noise came more regular. It ended up knocking out 3 sets of injectors before I realized it was improper signals from the ecm causing the whole problem. ( the noise was the injectors reacting to the mixed signals)
drivability was slowly getting worse and had head temp topping over 490 deg. Exhaust pipes even glowed red! NASTY HOT! My dealer was not much help, sorry to say, and told me thats normal. I did replace the module with a Thunder Max and it runs great and never again made the noise. Head temp now around 220 deg.