I will try to set this up the best I can.... I bought an 07 YZ450F last month and absolutely love it. Great looks and runs as good as it looks. I had it jetted and dyno'd last week, 155m, 45p, and 3rd clip on the needle. I live in the Rocky Mountain region of Montana and ride at or above 3000'. After jetting, my bike runs better than with the stock setting, which ran rich, but I am still noticing what sounds to me like the engine is pinging at low rpms. I have been running pump gas through it and not sure if this is the problem or if it may be something else. Any ideas as to what I should do next?????