engine tune up & exhuast ports



Hi Guy's,

top website very intresting i have question,

1. How many turns do i need to turn out the mixture screw from fully close position on top of carby

2. How many turn do i need to adjust the idle screw on side of carby

Iam currently doing 46km on flat straight with 80cc chineese motor and short chrome pipe from grubee.

also what i noticed that the cylinder head has a square output flow where the gasket and muffler has round port which limits the exhuast flow limit

any view be appreciated



Hey, that sounds like the carb i have. The first screw you're talking about sounds like the screw to adjust the cable slack....but if i'm wrong, tell me. The idle screw: adjust it so that it idles good when you disengage the clutch. What i did when adjusting mine was look to see how much of a gap there was from the bottom of the barrel (thing that slides up and down in carb) to the bottom of the bore ( i'm not sure what to call it? the gap between the bottom of barrel to the lowest part of the bore going through the carb) i think that makes sense... do u have a picture of your carb? my engine also has a squarish shaped opening to the exhaust and intake, and both gaskets are round in the center.