I'm not sure about the black head, but I have the gold head Pixie. Which was the 3 port; the black head was a 5 port. My real head clearance with no shims was .64mm. At this clearance I can run 30% with no shims. I believe the head clearence is a little excessive with no shims. I replaced the original carb with an OS speed tune carb. The engine runs great on higher % nitro. It won't idle very well when running 16% even with a hot plug.


Pass you soon...