GP 175 12v. Only done 500 miles since rebuild with new loom, ignition etc. Can't find any loose wires, horn and lights work and scooter running perfect. Just won't switch off, have to stall it! MOT due this week too! Help!
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Scoot won't turn off!
- coaster
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If you look at the CDI you will see 2 greens plugged in together (they are connected together via the CDI) , one comes up from the stator and the other goes into the loom with its other end in the headset. In order to kill the engine that headset green gets connected to earth through the ignition switch when you turn it to the off position. It is possible that the earth to the switch has fallen off or the green is nor connected at one end or the other. It's also possible that the switch is faulty.
Hope that helps
Hope that helps

- garry inglis
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as coaster spot on
- scooterslag
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Had a similar problem with a PK125XL years ago, I'd go for a ride, try and cut the ignition and it wouldn't work, turned out to be a over jetted carb and too hot a grade spark plug , correct jetting and plug installed and problem solved
The mack daddy on the left!
But it's run fine from being built! Checked all wires, cdi etc. Guess I'll check again! Thanks for your help guys
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- coaster
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Remove the green from the CDI that goes into the loom. Now connect a wire between the CDI Green terminal and earth and try to start it. It should be imposible to start, Disconnect the wire fro the earth and the engine should now run but touching the wire to earth should kill it. If that all works then you KNOW that the fault is in the headset or the wire between it and the CDI.Spider wrote:But it's run fine from being built! Checked all wires, cdi etc. Guess I'll check again! Thanks for your help guys
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Good luck

- Toddy
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coaster wrote:Remove the green from the CDI that goes into the loom. Now connect a wire between the CDI Green terminal and earth and try to start it. It should be imposible to start, Disconnect the wire fro the earth and the engine should now run but touching the wire to earth should kill it. If that all works then you KNOW that the fault is in the headset or the wire between it and the CDI.Spider wrote:But it's run fine from being built! Checked all wires, cdi etc. Guess I'll check again! Thanks for your help guys
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Good luck
^ + 1, Same Check i would do
As my Dad used to say "Each to their own lad"
The earth being yellow on the CDI? Sorry, I'm useless I know!
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- HxPaul
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Connected to the CDI you have a white,red and two green wires.Dis-connect the green that goes down the main loom,now plug a piece of wire onto this terminal,start the scooter and with the scooter running touch the engine with the other end of the wire that you have just connected to the CDI,the scooter should stop,if it does the fault is at the kill button/ignition switch end,or a break in the wire in the loom.