Here's a photo showing too much T-slot exposed at idle.

Bullit, either check this or confirm that it's A-OK before we do anything else. You've checked your timing and it's where it'll stay, so this is the next thing to do before changing anything else.

Your engine is small enough and mild enough that I don't expect this to be a problem in your case, but we can't assume it's correct. There's an old saying about what happens when wee assume...let's see, how does it go...hmmmm?