After I did the rebuild on my bike it ran fine and i didnt run it hard for an hour or so. Well after i heat cycled it a couple of times and a couple of days later i let my friend ride it. He ran it pretty fast after it was hot and said the bike wasnt getting into its powerband. I checked this today by riding it and warming it up and letting it get hot then getting down on it and it seems to want to get into the powerband but then its got that kinda cold pinging sound like when you try to rev the crap out of a 2 stroke before its warm i've never tryed it but heard it. It's like that sound. The guy who had the bike before me ran 40:1 Gas/Oil and i switched over to 32:1 for the rebuild. I'm thinking when I added more oil didn't i lean out the fuel mixture? Should I try 40:1? I really want the powerband fixed. thanks guys.