I have a problem with my 2006 WR450F that has been driving me crazy and I'm out of ideas If the bike has been sitting for more than a week it is an absolute biotch to start. If I ran it yesterday, it fires right up. It has always had this problem since I bought the thing, but it seems worse as of late. My first suspicion was that the fuel cock was leaking a tiny bit over time and ever so slowly flooding it. I replaced the fuel cock and when I had the carb out replaced the float needle and seat. I have tried starting it with fuel cock off, no choke and throttle at WOT (like starting a flooded engine)......nothing. When it is difficult to start I do not smell gas, it does not seem to be flooded When I spray some starting fluid at the air filter it does not seem to have any effect (every other engine I have ever put starting fluid to lights right up) I suspect, but I am not 100% sure, I actually have a lean condition and not flooding I just recently had the shop shim the valves it is running the stock 65 starter jet and I have a dynojet kit in it that uses an O-ring to make the accel pump come on earlier and easier I have al the other jetting info if that is needed or relevant (otherwise it runs beautiful) .......Any ideas?