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Discussion Starter · #1 ·
Hey guys, I’m in desperate need of some help in choosing which spark plug to run in my machine. I have stage 3 cams, 13:1 high compression piston, FCI intake, PC5, and auto tune, my quad runs perfectly fine tell the plug gets to hot. then it bog’s down and then won’t start tell it cold, when it’s cold it runs perfectly and then it will continue to do that, so I’m trying to figure out which plug to purchase that runs way hotter then the Stock plug, I’ve tried both that kawi recommends and it doesn’t fix the problem, so I need a different one, any suggestions?
 

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Hey guys, I’m in desperate need of some help in choosing which spark plug to run in my machine. I have stage 3 cams, 13:1 high compression piston, FCI intake, PC5, and auto tune, my quad runs perfectly fine tell the plug gets to hot. then it bog’s down and then won’t start tell it cold, when it’s cold it runs perfectly and then it will continue to do that, so I’m trying to figure out which plug to purchase that runs way hotter then the Stock plug, I’ve tried both that kawi recommends and it doesn’t fix the problem, so I need a different one, any suggestions?
The stock plug is all that’s needed.

sounds like your valves are in need of adjustment.

Or or or failing coil, failing fuel pump, bad tune
 

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Discussion Starter · #3 ·
The stock plug is all that’s needed.

sounds like your valves are in need of adjustment.

Or or or failing coil, failing fuel pump, bad tune
It’s at the shop now and I’ve spend $2500 CAD for them to go over the whole thing and replace what doesn’t check out, after a few replaced parts, everything checks out now but it’s still bogging when its hot, like it starts and runs amazing cold but half way down the trail it Bogs and then I shut it off and it won’t start tell it’s cold, my buddy has a kfx 450r as well and we have swapped ecu’s, turners, and injector and fuel tanks and his quad ran great and mine had the same issue as before, any other suggestions?
 

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Discussion Starter · #4 ·
It’s at the shop now and I’ve spend $2500 CAD for them to go over the whole thing and replace what doesn’t check out, after a few replaced parts, everything checks out now but it’s still bogging when its hot, like it starts and runs amazing cold but half way down the trail it Bogs and then I shut it off and it won’t start tell it’s cold, my buddy has a kfx 450r as well and we have swapped ecu’s, turners, and injector and his quad ran great and mine had the same issue as before, any other suggestions?
it has had that valves adjusted and everything set top dead center, the timing is correct to the best of my knowledge, like I’ve tried everything except an engine swap really, The dealership pulled the wiring harness apart and checked for corrosion and there is no corrosion everything seems to be A-OK except they cannot figure out what is going on when it heats up, and this is the second dealership it’s been too
 

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it has had that valves adjusted and everything set top dead center, the timing is correct to the best of my knowledge, like I’ve tried everything except an engine swap really, The dealership pulled the wiring harness apart and checked for corrosion and there is no corrosion everything seems to be A-OK except they cannot figure out what is going on when it heats up, and this is the second dealership it’s been too
what about tps/coil?

How does it run on the stock ecu no tuner
 

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Discussion Starter · #6 ·
what about tps/coil?

How does it run on the stock ecu no tuner
It does the same thing on the stock ecu, and the tps is within spec and the coil was replaced, I’m getting so frustrated with this issue, and when I swapped tanks with my buddy his quad ran good and my quad with his tank still bogged when hot, so I would assume fuel pressure is good or his quad with my tank would have caused his machine to bog, any other ideas? Has anyone else ever had this issue?
 

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I had a similar issue. Turned out to be the coil wires had started to corrode inside the insulation. It actually turned to dust. When it was first started, it would be fine then as the wires heated up, it would kill the spark. Took me a year to find the problem…
 
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