Bambo, that's my idle adjuster.. It's from a Honda CRF450.. Works perfect with the WR.. just gotta cut a bit of the end off of it, then it fits good..
and the Bt003RS are pretty good.. Super soft, and hook up very well, haven't had it step out on my yet, and I push the bike pretty hard in the corners.. Not bad for wear either.. My current 150/60/17 rear has about 2000km on it and it looks new