Cheif,
This is Adam from Zipper's. I just wanted to chime in to tell you that 360 is WAY too hot, that is in the danger zone. You are at the heat treat temperature of the head castings, if you go much beyond that, or do not correct the current issue, something WILL fail. Let me repeat this to show the significance of your findings, 360 is DANGEROUSLY hot.
2 quick questions for you:
What EFI management system are you using?
Does your engine have any problems reaching 6000 RPM, or does it fall on its face at 4000 RPM? I'm simply curious if the problem is in the EFI management, tuning, or internal in the engine.
We at Zipper's have seen and read the thread called "Best AFR", and we are not ignoring the request for us to respond FYI. This is a Very tricky question because the truth to the matter is that there is no perfect AFR for these air cooled engines. We are having an internal meeting of the minds tonight and we're going to answer the question as best as we can. We did not want to jump in and say the first thing that came to mind, we have been evaluating this very topic on our dyno for quite some time now, coupled with road testing for rideability, throttle response, and heat during Actual riding. Please stay tuned for a much more detailed response on the AFR subject, either later today or tomorrow morning.
Thanks!
Adam