I have a taotao vip with 805 km I have broken it in properly and used only premium gas and changed the spark plug to an NGk iridium. It will idle really slowly like at 900 rpm then goto 3000 it cannot stay inbetween there. It runs perfect otherwise tho. Any ideas?
Don't know if it's the same problem as you're having, but on my 150cc Taotao it would idle at 1,800 rpm when cold and 2,800 rpm when warm, so when the engine was warm, it wanted to engage the clutch and made the bike jerk a little without touching the throttle. I dialed down the idle speed screw about 1/2 a turn. Here's the video of what I did although the CY50A is probably a bit different:
The only problem I have on my EVO with starting, is that when I fill the gas tank too high, the gas tank overflow goes through the vacuum lines into the carburetor, causing a rich mixture, and engine bogging/stalling when idling.
When the gas level is about 1 to 2 in below the top the overflow mainly sucks up gas vapors. These gas vapors actually make the air / fuel mixture richer, and cause a better explosion; (instead of fuel mist or damp, mixed with air, now they mix air with fuel fumes, which is way smaller drops than damp or mist).
My EVO does idle between 1200RPM and 1800RPM, between cold and hot.
Last Edit: Apr 5, 2013 23:33:43 GMT -5 by prodigit
Should idle high when its cold and slow down once warm , when its cold outside . My Ecxharm with EFI it is always the same from 17 degrees to 100 outside . If you idle speed is jumping up and down check for a leak at the intake which many are Teflon and will dry out , crack and get holes and check the vacuum lines too