i have a 150cc quad i dont know wont make it is it has not got a kick start just electric start but it will not start there is no spark and i have put a new coil on it and still no spark and i tested on old one and it work fine plz help thanks  

The first thing to do is check the easy stuff:

1) Double and triple check the kill switch (or switches).  My quad has three - one on the left handle bar, the ignition switch, and the a tether strap dead man switch.  If any of these switches are closed (terminals shorted together) you can crank all day and get no spark.

2) Check for loose connections at the CDI, coil, and two bullet connecters between the stator and the cdi.

After that you need a voltmeter.



While cranking measure both the DC and AC voltages on the kill switch connection at the CDI.  One lead goes to the kill switch pin and the other goes to engine ground.  Use a straight pin to probe through the insulation of the wire directly into the inner copper if you can't get past the seals on the back of the CDI connector.  There should be high voltage on this line - DC pulses going up to over +100 volts peak so mind your fingers while doing this.

Next measure the AC voltage from the Ignition Power winding from the stator.  You must disconnect the CDI while making this measurement to get any meaningfull results.  With the CDI disconnected measure from the connector wire to engine ground.  You should get about 85 volts AC while cranking.

Report back your measurements and we can go from there.

Also,  Do you have a wiring diagram?  I have one for my quad which I can post if you need it.  I had to trace out the entire quad since nothing was available from the dealer.  It is probably very similar to your wiring.  

ye can you post the wiring diagram plzzz  

jonny_g:
ye can you post the wiring diagram plzzz

The following two jpeg pictures show my 150cc quad wiring diagram.

To see the whole picture you will have to use the horizontal scroll bar underneath the second picture, else you can right click on each pic and select "save image as" to your hard disk and then look at it with your favorite image viewer program.



 

thanks alot