Direct Bikes 50cc Not Idling Correctly

Direct Bikes Moped 4 Stroke. 2013 plate.

It will not idle correctly. The revs seem to go up and down as they wish. I can adjust the idle or air and fuel mixture and then the bike still goes up and down. If I adjust the mixture to idle correctly the bike may cut out because the revs have decided to go down. Or rev too fast and back wheel starts to turn because the revs have decided to go up.

Any ideas?

 

Check for air leaks on the inlet manifold/carb, diaphram, valve clearance.

 

Will do tomorrow and let you know.

 

Yeah sounds like an air leak

 

Okay this one is resolved.

I checked the automatic choke. One of the wires was hanging on by a thread and then snapped. So I changed the carburettor and put a new automatic choke on to it. Started up immediately and the idle was perfect!

So it seems it was a faulty automatic choke.