I ride my '06 450 almost weekly and it recently started running like crap down low, it came on rather suddenly and is somewhat intermittent. It is very hard to start sometimes and when warm it wont idle at all. I replaced the pilot jet and cleaned the carb twice. Checked the valves and the exhaust looks good but 2 of the intake valves are on the tight side of spec but are in spec if Im doing it right. I have never had to adjust the valves but these are the tightest they have measured. My gut says it is carb but I am unsure. The choke has been bent for about a year but opens and closes good. Plug is black and new, should I adjust the valves to loosen then up a bit or try to clean the carb again or what? Thanks in advance for any advice you can give, thank goodness my nieghbor has a yz125 I can ride because Im jonesing xhard.