Hi all been having a problem with my 03 250 pro loosing it's spark, I started a while ago now where it might cut out half way round a trial it would loose spark for a few mins and then go again it's got to the stage now where it will run for about 10 mins then loose spark for about 10mins before going again and so on. I have changed plug kill switch, checked all wiring and connectors etc even moved it all around while bikes running but have no joy finding problem. It only ever cuts out on low revs and feels although I've stalled it. Does anyone know of if it could be stator, ignition coil or cdi and how to check these accurately. Thanks Jon

it could be the wotsit on the thingy ,try getting a good sparky that could check it for you boy ,

It sounds like the stator. when the bike warms up the heat affects the insulation on the windings of the coil and you lose spark. You will find wiring diagrams with resistance values for your bike here

Could be coil, too.

When they go tits-up, they generally work until they get warm and cut out.

I suppose you could run it until it quits, then take a reading between the LT and HT terminals.

Hi John,

If your bike has Kokusan ignition, then it is likely to be an earthing problem, perhaps the voltage regulator under the headstock, if it is a Ducati ign system, then it is likely to be the aluminium electronic box under the tank. Substitute this for another to confirm. If not this, then it will be the stator.

Bye, PeterB.