Originally Posted by rslavicek
Is there any trick to getting an 80 cc engine to idle. I'm still at the start of my break-in period and I've played with the idle screw, but it dosen't seem to make much difference, as soon as my hand is off the throttle the engine dies. It's not much of a problem since the motor will restart after a couple of pedal strokes. Would adjusting the throttle linkage help or will the problem go away after the engine is broken in?
This is a Manic Mechanic "How To"
The Idle screw is not for the conventional, Air/fuel, mixture adjustment that you may be accustomed to! It is actually a stop for the carb slide. These carbs do not have a high/low circuit.
DO NOT attempt to make this adjustment with the engine OFF...You may create a burr on the Carb slide!
DO NOT turn the idle screw without cracking the throttle open...("the righthand-side twist handle that was provided in your kit for the throttle").
It is difficult to describe how to do this, but it is so easy to do!
Ideally a helper will hold the clutch lever. If a helper is available...simply keep the engine running, (Rev the engine!), and turn the screw clockwise as though you were looking at it head-on. At some point you will be able to return the throttle to idle and the engine will not die. If the idle is too high, back the screw off counterclockwise until the idle is correct...done.
Simply ride the bike cracking the throttle at a low cruise speed and turn the screw clockwise as though you were actually looking at it head-on.
Turn the screw in half-turn increments and return the throttle to idle. When you get to the point that a return to idle keeps the engine running, pull in the clutch and stop. The idle will likely be high...back the screw off, (counterclockwise), until it idles normally.