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This is interesting. I would like to know also if there is another spark plug that is one step colder than the oem ngk spark plug.

From what I know ngk is one step colder than denso spark plugs. So it's a good thing we have ngk as oem spark plug. :)
 

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You guys do know that "hot" or "cold" on a spark plug is just a matter of the insulator shape and it's join to the metal body, right? A "cold" plug transmits more acquired combustion chamber heat to the cylinder head. A "hot" spark plug has more exposed insulator (acquires more heat) and less ceramic insulator material connected to the metal body so it sheds less acquired heat into the head and stays hotter.

A spark plug has to be "hot" enough to resist fouling at low engine temperatures and speeds. It also has to be "cold" enough to avoid detonation at high engine temp/speed. Higher-performance engines, generating hotter combustion-chamber temps, need a colder spark plug to keep the plug tip within the ideal operating range.

Now that I'm thinking about it, I wonder if my bike (143cc BBK and V2 race head) could benefit from a plug colder than stock.
 

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You guys do know that "hot" or "cold" on a spark plug is just a matter of the insulator shape and it's join to the metal body, right? A "cold" plug transmits more acquired combustion chamber heat to the cylinder head. A "hot" spark plug has more exposed insulator (acquires more heat) and less ceramic insulator material connected to the metal body so it sheds less acquired heat into the head and stays hotter.

A spark plug has to be "hot" enough to resist fouling at low engine temperatures and speeds. It also has to be "cold" enough to avoid detonation at high engine temp/speed. Higher-performance engines, generating hotter combustion-chamber temps, need a colder spark plug to keep the plug tip within the ideal operating range.

Now that I'm thinking about it, I wonder if my bike (143cc BBK and V2 race head) could benefit from a plug colder than stock.
That's what I'm wondering.. I have 143, v2, 32mm throttle body, and full port work, intake exhaust, blah blah blah lol.. grabbed a "one step colder" plug but not sure if I'd benefit putting it on.. I know I have higher compression now, but I don't want to run to cold of a plug either..
 

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...but I don't want to run to cold of a plug either..
Isn't the risk of running too cold of a plug simply premature plug fouling and misfires? Seems worth trying if you already have the plug on hand.

Someone please correct my misinformation if this would actually put his engine at risk.
 

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Ok, good deal. My tuner got back with me and just said that sometimes they don't start as easy if the plug is too cold so that he just puts his in when it gets hot outside. I'm just going to throw it in and if it starts just fine now while it's freezing outside, then leave it. Thanks for the info guys
 

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I finally put my Iridium/IX plug NGKCR6HIX/7274 in last week and after 5-6 cold starts now it definitely helps start my bike 30 to 50% faster anything under 50 degrees
 

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