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Spark Plug Heat Ranges

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Old Jun 19, 2011 | 10:50 AM
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Navy UC Rider's Avatar
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Question Spark Plug Heat Ranges

Shipped my bike back to the states a couple months ago. Should be receiving it in another 3 weeks. Looking to change all my fluids and give a good going through before I get out to do some riding on some good American roads (assuming the bike shows up in one piece).

Spark plugs are on my list of things to change, I have been using the OEM plugs (slight pinging), but I was thinking about a plug in a colder heat range. I went down 2 steps on my Dodge Ram, seemed to make the pinging go away, would this work with our bikes also?

Thanks,
Cale
 
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Old Jun 19, 2011 | 11:44 AM
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So in Italy your bike pings? IMO, I would run HD plugs that is suggested & see what happens. Cale,thanks for your service.
 
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Old Jun 19, 2011 | 11:50 AM
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Spark plug types, heat ranges, manufacturers, stock vs gold, copper & platinum...etc, has been debated as much as which oil to use or which is better.

Generally, the "experts" agree that HD OEM plugs are too hot to start with & blaming EPA requirements seems to be the common reasoning. For an average stock to mildly modified HD street motor, a common practice is to go one range cooler & thats what I do. However, many will state differently & for various reasons & each will have valid points to support their reasoning.

It wont hurt anything to go 1-2 ranges cooler in a HD motor & in most cases there will be some improvement & others no noticeable improvement. In most cases only a comparative test on a dyno can see the difference, if there is one.

Heres a decent informative page to read: http://www.centuryperformance.com/sp...ch-spg-26.html

There are volumns of information on the net written on spark plugs.

Its best to be educated on heat ranges & decide for yourself.
 
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Old Jun 19, 2011 | 11:53 AM
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I switched to a NGK Iridium IX Plug purely on the recomendation from a guy who does a boat load of dyno work. I played around with plugs on an S&S 107" motor, NGK being one and not sure anything got any better. Actually ended up putting the standard Champions back in.

I'm going to run these Iridium plugs in this 2011 twin cam for a while and see if they make a difference over time, but if I've improved anything at all, at this time I'm not feeling it.
 
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Old Jun 19, 2011 | 12:03 PM
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Originally Posted by 103 sedona orange
So in Italy your bike pings? IMO, I would run HD plugs that is suggested & see what happens. Cale,thanks for your service.
Yeah, the bike pinged, mostly under load climbing through the mountains. Fuel Moto has been great over the last year or so, helping me out with MAPS. The fuel we run here is actually 95 octane (AGIP or ESSO), so it should be good to go. I have changed to the SE Plug Wires and the $3 HD Gold plugs. I really cannot complain about the back, had more problems with my Honda when I got here, then with the HD, so I am a happy camper.
 
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Old Jun 19, 2011 | 12:15 PM
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Originally Posted by Fast Aire
Spark plug types, heat ranges, manufacturers, stock vs gold, copper & platinum...etc, has been debated as much as which oil to use or which is better.

Generally, the "experts" agree that HD OEM plugs are too hot to start with & blaming EPA requirements seems to be the common reasoning. For an average stock to mildly modified HD street motor, a common practice is to go one range cooler & thats what I do. However, many will state differently & for various reasons & each will have valid points to support their reasoning.

It wont hurt anything to go 1-2 ranges cooler in a HD motor & in most cases there will be some improvement & others no noticeable improvement. In most cases only a comparative test on a dyno can see the difference, if there is one.

Heres a decent informative page to read: http://www.centuryperformance.com/sp...ch-spg-26.html

There are volumns of information on the net written on spark plugs.

Its best to be educated on heat ranges & decide for yourself.
Thanks, I searched HD Forums before asking, there was a lot of spark plug info, not really a lot on heat ranges. I am leery about using a non-OEM plug, because of the resistance being matched to the overall system (knock sensors, etc...). Like in my truck, I went to a 180 degree thermostat (not an option here) and a colder plug (could be an option), problem solved. Thanks for the link, I will be doing some reading.

Cale
 
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Old Jun 19, 2011 | 12:43 PM
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I'm currently doing a spark plug heat range experiment, no results to post yet. Using stock HD 6R12, colder Autolite 4163, and even colder VROD HD 10R12. I am considering a theory though; colder heat range plugs remove heat from plug tip faster to mitigate the hot spot and prevent preigntion, but the heat conducts out through the head, so does a colder plug actually raise CHTs and thereby oil temps? Will post something soon as I can.
 
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Old Jun 19, 2011 | 01:00 PM
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Originally Posted by fabrik8r
I'm currently doing a spark plug heat range experiment, no results to post yet. Using stock HD 6R12, colder Autolite 4163, and even colder VROD HD 10R12. I am considering a theory though; colder heat range plugs remove heat from plug tip faster to mitigate the hot spot and prevent preigntion, but the heat conducts out through the head, so does a colder plug actually raise CHTs and thereby oil temps? Will post something soon as I can.
I found a thread from 2007talking about cooler plugs. iClick said he is using the 4163, however he did not ping prior to his switching.

Another comment was that a bad tune is most likely one culprit. I have FM MAPS, I know every bike is not the same, but I feel confident I have a good tune.

I will wait for some info from you, plus I will ride the bike in the states for a little while. There could be a difference in formulation of the gas between Europe and the US.

Cale
 
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Old Jun 19, 2011 | 01:29 PM
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Originally Posted by Fast Aire
Spark plug types, heat ranges, manufacturers, stock vs gold, copper & platinum...etc, has been debated as much as which oil to use or which is better.

Generally, the "experts" agree that HD OEM plugs are too hot to start with & blaming EPA requirements seems to be the common reasoning. For an average stock to mildly modified HD street motor, a common practice is to go one range cooler & thats what I do. However, many will state differently & for various reasons & each will have valid points to support their reasoning.

It wont hurt anything to go 1-2 ranges cooler in a HD motor & in most cases there will be some improvement & others no noticeable improvement. In most cases only a comparative test on a dyno can see the difference, if there is one.

Heres a decent informative page to read: http://www.centuryperformance.com/sp...ch-spg-26.html

There are volumns of information on the net written on spark plugs.

Its best to be educated on heat ranges & decide for yourself.
Excellent article. Thanks
 
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Old Jun 19, 2011 | 01:40 PM
  #10  
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you would be trading one problem for another. the anti knock system is hooked into the values of OEM and equiv spark plugs.
 
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