Hey guys...First off, thanks for all the great posts...Most helpful site/users ever...And sorry for popping so many questions into one post...If that's taboo, I'll just chalk it up to being a newbee... I just picked up a new 07 YZ450F (the white one) from LA Yamaha (Marina Del Rey) for $5600 OTD about a month ago...Been having a blast breaking it in (stock + ASV levers) at LEMX (Lake Elsinore Motocross Park)...Just bought a complete WB Aluminum Pro II kit today for $325 at Del Amo Motorsports blow out sale (couldn't pass on it being more than $300 bucks off)... My first question is, will I need to rejet due to the new pipe? And if so, what do you recommend? (Pretty much the only places this bike will be ridden is Glamis, Pismo, Ocotillo, Gorman, and SoCal MX tracks)...I was already considering sending the carb to Zip-Ty due to the numerous pops on decel...Should I just stick with that idea? Secondly, I almost purchased a DID O-ring chain, but was told that it wouldn't make sense since riding in the sand or loose dirt would contaminate the rings to where they aren't performing the way they should anyway...So which chain should I spring for? Well, I have a few more questions, but since I'm typing a novel, I'll leave it at these for now...Thanks in advance!