Break In Phantom 85 “pop” and then died and won’t start on first ride

Chris117

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After much help from the useful moderators on this forum I was finally able to get my phantom 85 build firing up, only problem is on my first REAL test ride at about 5 miles in while I was giving it low throttle it made a sudden “pop” and then died and I couldn’t get it to start anymore. I was running the engine a little lean so when I got home I adjusted the “C” clip into the middle but it won’t fire up anymore. After a while I’ll try agian and I’ll the the occasion “pop” “pop” but no real acceleration or consistent combustion and then it stops and just turns over. I’ve rechecked my electrical components and they read OK. I’ve also noticed a few leaks at the base gasket and noticed a tear on the Exhaust gasket but I wouldn’t think it would be enough of an air leak for a no start. This was the clearest photo I could take of the tear. I’ve taken the cylinder head off and no damage to piston or cylinder. I don’t think my kit came with 2 gaskets as everybody seems to say they’ve received. But there’s no clear sound of an air leak like some I’ve heard my head nuts are torqued to 12 ft pounds like y’all have suggested.
 

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Tighten the plug and head bolts to start with. 144 inch lbs on the head bolts and just snug on the sparker.
 
just snug on the sparker.
More than that, leakage from spark plug shows it is not sealing properly...If that is the crappy Chinese Z series spark plug, throw it away and replace with a NGK-BR6HS spark plug gapped at .025 (thousandths).

I’ve heard my head nuts are torqued to 12 ft pounds like y’all have suggested.
Also known as 144 INCH pounds if you are using a 1/4 inch drive, INCH pound torque wrench.
 
More than that, leakage from spark plug shows it is not sealing properly...If that is the crappy Chinese Z series spark plug, throw it away and replace with a NGK-BR6HS spark plug gapped at .025 (thousandths).


Also known as 144 INCH pounds if you are using a 1/4 inch drive, INCH pound torque wrench.
I have a E3-32 plug, I bought a NGK B6hs but the threads are too long and the piston would hit it, I did notice that there’s one with some sort of protection and the other does not. I’m returning it.
Edit: the tear is about 11mm
 
That's why you need the NGK Bpmr7a
Now tell him why he needs that plug Gordy...lol.

Chris117 has only one bottom base gasket and not the two that are supposed to be on the Phantom and that is why the usual NGK-BR6HS seems to be too long...lol.

The NGK-BPMR7A plug has a shorter reach therefore will not have the piston hitting it because of the only one gasket on the bottom end...lol.
 
Now tell him why he needs that plug Gordy...lol.

Chris117 has only one bottom base gasket and not the two that are supposed to be on the Phantom and that is why the usual NGK-BR6HS seems to be too long...lol.

The NGK-BPMR7A plug has a shorter reach therefore will not have the piston hitting it because of the only one gasket on the bottom end...lol.
Well I would if you didn't tell him for me lol
 
Now tell him why he needs that plug Gordy...lol.

Chris117 has only one bottom base gasket and not the two that are supposed to be on the Phantom and that is why the usual NGK-BR6HS seems to be too long...lol.

The NGK-BPMR7A plug has a shorter reach therefore will not have the piston hitting it because of the only one gasket on the bottom end...lol.
That one looks like it has a tapered seat, it will work but from this chart you would want a BPR7L or BPRS7

 
More than that, leakage from spark plug shows it is not sealing properly...If that is the crappy Chinese Z series spark plug, throw it away and replace with a NGK-BR6HS spark plug gapped at .025 (thousandths).


Also known as 144 INCH pounds if you are using a 1/4 inch drive, INCH pound torque wrench.
After taking the head off and inspecting I have found that the oil and gas was not seeping through the base gasket and that I in fact do have 2 gaskets installed and the gas and oil is leaking through the exhaust gasket. I also know there’s power to my spark plug because I held on to it while I peddled and is zapped the hell out of me.
 
Also there’s like extra metal bur in my engine body should I file that off?
 

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