Burning plastic ?

Since your bike is somewhat new I wonder if its the exhaust sytem maybe the CAT meterial "burning" in. Just a suggestion ( im pretty sure I pulled that one out of my arse!!!)

mutt
I vaguely remember such a plastic like smell in th early daze. And it burned off.
 
i had that too...i reckon it was the cush drive wearing itself in to the back hub, smelt more rubbery to me