I just bought a 98 wr400. And I am going to get it street legal. I'll be riding it to school and work in Rexburg, ID. I am looking at the Maxxis M6006. Read some great reviews on the tire. I am wondering can I run a 140/80-18 on the rear? It has a 120/90-18 on it right now. Is that two wide for a stock swing arm? Will my chain eat the side of it?