06-300 not running
 

My 300 is sick. It fires up runs for a bit than dies. Pulled the plug and checked for spark - none. Waited five minutes checked again have spark now put plug back in and it starts only to die again in a couple minutes. This same routine went on 3 or4 times. About two weeks ago I tore the little black box off the coil. Parts finder calls it a regulator/ alternator. I kept riding the last two weeks without it even did a race and it ran fine. Could I have fried the coil I assumed the little box was just for lighting. Any ideas?
Dave

Yes, the little black box is for the lighting output (yellow wire). If you don't need lights, my suggestion would be to make an ignition only loom. Get rid of the handlebar switch and replace it with a simple engine stop switch. Less to go wrong. Study the wiring diagram in the manual and it's fairly easy to work out. Also check under the ignition cover. If there's any sign of dirt in there, you're going to need to pull the flywheel and remove the plate and clean everything. The '06 cases can let in water, and when dirt carried in the water gets onto the crank, it can wear out the main bearing seal, and then the main bearing.

300 sick
 

Okay, so running without the little black box won't hurt the coil. I don't have a light switch on the bars just a kill switch. I check under my ignition cover quite frequently and it's clean. I'm still thinking coil though, how can I test it?
Dave

have you tryed a new plug, could be buggered :)

Sick300
 

Have tried three different plugs. Same thing. Now I have no spark at all. Starting to think it could be a broken wire in my harness. I'll strip the tape off and start checking. Just to rule it out is there a way to check the coil?
Dave

I reckon you could check the resistence of the coil, but what reading to look for, I don't know. What is the join between the coil and the HT lead like ? - that can get loose over time. The wiring loom is probably the element most prone to damage and time spent checking through that would be well spent.

Make sure you have good earth point(s) also as caravan monster suggests go through the loom.
Buy a new coil & HT lead

It could also be a faulty kill switch

i dont know how to check a coil to be honest

i think you have got to check the loom over to see if there is a problem and as savage said the earth on the coil. i would clean and WD40 all the connections (connectors) oh savage bought up another good one about the kill switch just disconnect it and check for spark. has it got a ignition barrel.

what i would do is start at one end say the stator plate working up after checking a section try and see if there is any change, sorry i cant be more help :)

300-happy
 

I think I have it sorted out. Took apart the HV coil lead , it was loose clipped the ends and installed a fresh cap. Also found a loose connection at the CDI , cleaned up all wires and connections. Bike fired up and I took it for a good blast around the farm, no problems. Tommorow I'll give it a good run on my home track which is some of the most disgusting real estate in the pacific northwest.
Anyway thanks everyone for your help and suggestions .
Dave

I have an 06 300 and very similar problem as well, my remedy was the spark plug boto itself had zero resistance, $ 2.95 later it was fine for three weeks of hard single track. last night it just did on me after 30 seconds of riding...have a weak spark, might throw a new coil in.