2007 K9 BigDog won't start after warming up.

[Graffster]

My K9 will not restart again after its warmed up.
There seems to be no Spark at the plugs?
If I leave the bike to cool down for a while it will then start and run ok.
Before I go ahead a spend money on something that might not be the problem.
Has anyone else had this problem before? and what did you do to fix it?
I have checked the sequence of LEDs while starting and it seems to be all ok there. Could it be a faulty Coil?

 

[FrankBDPS]

Are you getting power to the coil while turning it over?

 

[Graffster]

I haven't got that far into it Yet but no spark at the plugs when it cranks over warmed up sort of tells me it's the coil or back from there?
The problem is I am normally out on the road when this happens! So when it does fire up I can not trace the problem. That's what makes me think the coil is breaking down on warm start up. But the bike runs ok once started.
My K9 is a Carburated 2007 Limited Edition.
Must be someone out there that has had a similar issue?

 

[Sven]

My coils (assuming) would breakup right before they take a shit.
My coils come back on line when my crank sensor cools down.
My coils need a trigger to cause spark.

So, here I am riding along with a wire dangling off the + side of the coils.
So, here I am off to the side of the road no spark.
So, here I am with key on, take the wire and ground it, with a spare plug sitting on the head with the plug lead showing me I have spark manually with the wire, but no spark with the starter rolling the engine over.

I now show my coil has integrity.
I now show my crank sensor is the other variable to no spark.
I now show myself if it's the C/S or the Coil.

Make sense?

 

[07bigdog]

My 2007 K9 would shut down once it would warm up. If you let it cool down for an hour or so, it would fire right up. As soon as it warmed up again it would shutdown. My whole charging system went out. I changed the stator and rotor, crank position sensor and voltage regulator and has been running great for a year now.

 

[blacktopper]

My K9 will not restart again after its warmed up.
There seems to be no Spark at the plugs?
If I leave the bike to cool down for a while it will then start and run ok.
Before I go ahead a spend money on something that might not be the problem.
Has anyone else had this problem before? and what did you do to fix it?
I have checked the sequence of LEDs while starting and it seems to be all ok there. Could it be a faulty Coil?

My 07 K9 had a similar issue. Turned out it was the red wire to the ignition module wasn't making a good contact in the JST connector(it had backed out a little). Does the red light on the ignition light come on when you hit the run button? If not check that connector.

 

[Graffster]

(07bigdog)The bike does not shut down, not until I shut it off, then it Just cranks over but will not fire?

(black topper)when I turn the ignition on there is a orange/yellow light and a flashing green light. When I push the run button the red light comes on. It fires up cold but will not warm!!

 

[blacktopper]

Does the red light come on when it's warm and doesn't start?

 

[Graffster]

I think so,but I'll take it for another ride and check that.

 

[Graffster]

Just rode it again and when I got home it wouldn't start???
And yes the Red light comes on when pushing the Run button but still no go!

 

[Marky-Marc]

Check your Cranksensor plug and wire...that's where I would start.

 

[bearman]

My vote would be crank sensor. Very easy to trouble shoot, you just have to be able to see the ignition module. I had to take off the left side panel to see mine ('06 Mastiff).

You should have three LED's on your ignition module. The red will light up when you hit the run button, the yellow and blue should blink alternately (and your red one might dim) when turning over. If your crank sensor is bad the yellow and blue LED's will not blink. If the red LED doesn't light up when the run button is pressed (after the key is turned on), then either your Ignition module is bad or you are not getting 12 volts to the ignition module.

When my crank sensor went out, I got a crank sensor for a Harley. Of course the plug wasn't the same so I cut off the plugs from both and soldered the old Big Dog plug on the new Harley sensor wires. But if you got some time, you could order one from the Kaptain.

 

[BigDogBro1]

Crank sensor. Mine has been acting up about 20 minutes into the ride consistently this year and once it cooled down it was fine.

 

[Graffster]

Thanks heaps for all the input guys. I think I'm getting closer to finding the problem.
Now that the bike has cooled down I have spark at the plugs again!
I done a visual check on the sensor and wiring and look ok on the outside!
Would the engine heat effect the crank sensor? I'll ride the bike again tomorrow and see if it starts again after that.

 

[bearman]

...Would the engine heat effect the crank sensor?....

Yes.

Absolutely.

Without a doubt.

And eventually it will not work at all, even after cooling off. So if you don't want to be stranded somewhere, do your warm up test at home.

When mine went bad, it would only quit when it was really hot, like when doing stoplight drag races to the next red-light , in stop-and-go traffic. And mine would quit when the RPMs dropped to idle, even with the key on.
I was on a group ride and after about the third time it died, I realized that it was dying at Idle. So after I let it cool and got it cranked, I raised the idle to about 1400 RPM and took it easy, and it ran till we stopped for lunch and I turned it off.

It would never start again on that crank senesor.

 

[Graffster]

Thanks for the advise bearman, got one coming DHL.
I have had and still own many Harley's and have never had this happen! that's why I was all confused.Lets hope this fixes it.
Drag racing between lights, never done that before lol haha

 

[bearman]

....Drag racing between lights, never done that before lol haha

Me either, especially on a 6-lane street (3 each way) with 2 Japanese cafe racers in the far right lane, 2 Harleys in the middle lane and a whole pack of Big Dogs stopped in the left lane when the light turned green.

I'm pretty sure neither one of the 2 K9s in the front row meant to hurt the feelings of them Harley riders or them rice burner riders (OK, maybe a little) but them other riders sure seemed surprised and generally unhappy when they finally caught up to us at another light about a mile down the road.

They didn't try to keep up anymore. :roll:

 

[Graffster]

Thanks for he info Mr bearman, sounds like similar symptoms I have, got a new crank sensor, plug leads and plugs, on the way. Drag racing between stop lights haha never done that lol yeah right.