Checking the Timing

ELECTRONIC – INTERNAL ROTOR

There are two reasons that the Motoplat ignition does not create a spark.  First, for some unknown reason an internal short occurs and it just quits.  The second is the more likely and that is what I will address.  There is no way that the ignition can be damaged for the spark to be lost by removing the flywheel and stator unless there is physical damage inflicted on the unit by carelessness with tools.  Knocking it off with a hammer would be one of these.  Removal with a proper puller of the flywheel and removal of the stator with a common screwdriver is not.  There is a greater amount of heat and vibration occurring during engine operation then proper removal and assembly can afflict.  These are the things to look for:

1. Check and reset the timing if needed. 
2. The ignition coil on the frame must have the metal mounting tab in contact with the metal surface of the frame. 
3. Check all wiring for any breaks.  This is easily done with your volt-ohm meter on the ohm test mode.
4. The only way you can check for spark is to have the top end assembled and all of the electrical components hooked up.  Install a new spark plug into the coil cap of the high-tension wire, ground it against the engine, and rotate the engine rapidly.  This type of ignition needs to be spun faster than the external flywheel type because it has magnet proximity of lesser radius and the magnetic flux occurs with the passing of a magnet past the core to the primary coil windings.  If the kick-starter is unable to spin the engine fast enough then elevate the rear wheel, select top gear, and spin the engine using the rear tire. Note: These electronic ignitions can short in the stator if the components are connected and the sparkplug isn’t grounded when the engine is turned over. This is not a common problem but it never hurts to take precautions.
5. Disconnect the kill button and try again.  Some kill buttons will short.  The ones I use are an aftermarket copy of the two-wire Yamaha kill button.  I have not found any failure of this unit.
6. If these steps do not provide a solution then you can send it to Motoplat USA and they can test it.  It takes special equipment to do this.  The typical way a home mechanic tests the stator is to replace it with a stator on an engine that has proven spark.  Note:  You might think that the rotor may have lost its magnetism.  These are permanent magnets not provided by Lucas.  I have not found any to have lost any magnetism.  This may be a test performed by Motoplat USA.  Loss of magnetism is a rare ocurrente.

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