Hallo guys,i have a question,how do i use the timing chart to mod timing in a zenoah?the numbers shown in the list are mm's inches...lol,i just dont know.please i can port the cylinders pretty good,my problem is how much to take off at the intake and exhaust ports.i'm using a 0.05 mm gasket.raise..lower..how much,please help a noob from miami that wants to go fast..lol thanks