> Take some good clear pics of piston position (head off) in cylinder with
> relation to deck at tdc and exhaust/transfer ports at bdc with your
> current base gasket installed to visualize what’s going on in there.
> Might begin helping point to reasons for your carbon buildup.
Okay I finally got around to taking some photos. I’m running a 1mm base gasket, treats 70cc cylinder, & hi hi head with a 0.4mm head gasket