Scoot starts and runs fine but will not turn off by ignition

Hey Scoot, I need a little more info,, if you have removed the battery cables, you may have hooked something up wrong..Did you replace the battery?? ; hopefully with an exact match of the old one.. double check you connections and reply to me.

To do self diag on a pt u need to start with ignition off. Hold trip button in for the odometer keeping trip button held down turn ignition key to run then release trip. This will also run a self test on instrument cluster. Codes will be displayed in the odometer at the end of test

Definetly an air leak, I believe what is happening is where the inlet manifold joins the cylinder it has a poor joint which when cold is contracted and when engine heats up the joint expands with the heat,sealing the leak, ie causing the fuel/air mixture to become rich enough for scoot to run.

What make, model and year is it??

The internal combustion engine is quite simple. All you need for it to run is compression, fuel & a spark to ignite it. I'm not saying it'll do 40 MPH but it should start & run. If it doesn't then one of the 3 elements is missing.
You need the following - sounds stupid but it wont work if one of these is missing.
1. PETROL - fill the tank to be sure. If its a 4 stroke just petrol. If its a 2 stroke petrol & 2 stroke oil mixed or top up 2 stroke oil tank.
2. Fully charged BATTERY. Clean connectors on battery tops
3. a SPARK at spark plugs. Clean them while they are out. If no spark look for dodgy coils, plugs, HT leads, triggers.
Look for air leaks in fuel line - if bulb does not go hard you got an air leak. Does it smell of petrol? check for leaks in fuel line & around carbs, look for perished fuel line, loose clamps or if they are jubilee clips, they could be too tight, crushing the anti-syphon valves at the primer bulb. loosen them until squeezing the bulb scoots fuel out then re-tighten JUST enough to stop fuel leaking.
Does it turn over? - then battery ok & not seized
Does the choke operate? operate lever & confirm things turn properly on carbs.
Once its started you can fine tune it but it needs to start first!!

Your cold idle setting is wrong. You need to adjust that a bit higher. When your scoot warms up, it will drop back to your warm idle setting.
Go here and read
http://www.harley-heaven.com/M1105_idle_speed_MM.pdf

Semper Fi,
Z

probably the starter relay has a malfunction.
- Or the gears on the starter were once damaged when you pushed the starter button by mistake while the engine was already running?
Usually the engine starts on the second try - if the battery is really good then you better try to live with that.
Buy a Voltmeter to check the battery charge.



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Instructions

1.
The 2nd gear lockout is, a mechanical speed sensing mechanism. It doesn't care if the engine is running. You bypass it by scooting the bike forward, about 5-6 mph, while shifting the transmission into 2nd gear.
2

Stand on the left side of the bike, with the ignition "ON" and the transmission in neutral.
3 With your right foot on the ground, behind your left foot: place your left foot on the left foot peg, with your toe under the shifter; squeeze in the clutch.
*4.Scoot the bike forward about 5-6 mph, with your right foot, and shift the transmission into 2nd gear, with your left foot. If you accidentally go into 3rd, or some higher gear, you can easily shift back down into 2nd, without further movement of the bike.
5.To start the bike: Apply the choke if the engine is cold. Squeeze in the clutch and push the bike forward, both feet on the ground, about 8-12 mph. Release the clutch until the engine start
6
As soon as the engine starts: squeeze in the clutch and shift the bike into neutral.

sounds like the CDI module. I've had it go out on a couple scoots I've owned. Take it to a shop and have them check it