Question regarding new spark plug

Wrinkley

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I'm currently running this engine and I've seen that people recommend wwapping out the chinese spark plug with an NGK B6HS. Well I attempted to order one the other night after having a few drinks and I accidentally ordered a BP6HS. I realize that the P refers to a projected insulator, and after a little research people actually like utilizing them in their MB's. Prior to riding I made sure to turn the engine over by hand to ensure that the piston wasn't hitting the spark plug. It didn't seem to be, no real noticeable damage to the spark plug. I tried running it today though, and it would never actually get up and go. The engine just kind of lugged like it does when I'm first getting it started. Tested it with various choke positions, damn near identical outcome. I ended up letting the engine cool-down, took it out and took some pics of it. Seems to have some oil on it. Does this mean that it's running too rich and I need to adjust the carb?

Also, once the engine cooled down, I put in the original plug to isolate the issue and it ran just like it was when I was still using the original plug. Took it around the block and was it's normal old buzzing around self.

Lastly, I mentioned this in my last thread, my bike only runs when the choke is all the in the down position. If I lift it up, it will quickly die out. I'm assuming this is demonstrating a need to adjust the carb as well, correct?
 

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Chainlube

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I'm currently running this engine and I've seen that people recommend wwapping out the chinese spark plug with an NGK B6HS. Well I attempted to order one the other night after having a few drinks and I accidentally ordered a BP6HS. I realize that the P refers to a projected insulator, and after a little research people actually like utilizing them in their MB's. Prior to riding I made sure to turn the engine over by hand to ensure that the piston wasn't hitting the spark plug. It didn't seem to be, no real noticeable damage to the spark plug. I tried running it today though, and it would never actually get up and go. The engine just kind of lugged like it does when I'm first getting it started. Tested it with various choke positions, damn near identical outcome. I ended up letting the engine cool-down, took it out and took some pics of it. Seems to have some oil on it. Does this mean that it's running too rich and I need to adjust the carb?

Also, once the engine cooled down, I put in the original plug to isolate the issue and it ran just like it was when I was still using the original plug. Took it around the block and was it's normal old buzzing around self.

Lastly, I mentioned this in my last thread, my bike only runs when the choke is all the in the down position. If I lift it up, it will quickly die out. I'm assuming this is demonstrating a need to adjust the carb as well, correct?
The down position on the choke is the "off" position, take off your air filter and watch it work. When you lift up on the lever the little door will block the air flow. Carry on!
 

ImpulseRocket89

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The plug you put in and then took out (the pictures) has almost no plug gap. Looks to me like the piston tapped the plug just enough to close the gap off, and that is why your original plug made it run again - it's gap isn't shut.

Projected electrode plugs extend about 1mm further into the combustion chamber, which can be just enough to contact the piston on some engines. Even if turned over slowly and it seems ok, at high RPM the metal engine parts will actually expand and stretch just enough to close the gap that may have been there if it was extremely tight. I suggest going and getting the regular B6HS (I would suggest the NGK-BR6HS), or switching to a BPMR7A (or a 6), which does have a projected electrode, but is also physically shorter on both the insulator and threads (9.5mm vs 12.7mm) of the plug itself, so it won't hit the piston.
 

GW's Motorized

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You might try looking for one at your local auto parts store. You might be surprised at what parts they have that'll fit these. If you do decide to check the parts house, you might try an E3 spark plug, they burn really nice, and can boost your fuel efficiency if you tune the carb after.
 

DAMIEN1307

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You might try looking for one at your local auto parts store. You might be surprised at what parts they have that'll fit these. If you do decide to check the parts house, you might try an E3 spark plug, they burn really nice, and can boost your fuel efficiency if you tune the carb after.
Whenever you recommend the E3, you had best know what heat range number E3 that needs to be used...lol.
 

DAMIEN1307

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I tried one once for one hour and threw it out...I do exact gapping of my plugs and you cannot gap an E3 plug...Stick with the NGK-BR6HS and gap it to .025, (25 thousandths)
 

GW's Motorized

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The E3.32 is the plug you want if you go with E3...Most folks here have not found the E3-32 in their local parts store but that is the correct E3 plug for these China girls.
Ok, I had no idea there where different plugs. Now that I think about it I think I put a E3.32 in my 212 predator. LOL
 
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