spark plug
Unfortunately many people who post about plugs here do not understand the ION sense feature. I have seen people in this thread making posts in other places of the forum that basically any plug can be used, are just spreading bad information. In automotive and motorcycle applications that use the plug as part of the ION Sense circuit, plug and wire resistance are critical to the ECM making decisions. With that said, as in my posts #2 & #4, some cross reference plugs will work, and some will throw codes and cause all kinds of other problems such as the ECM pulling massive amounts of timing due to being confused about the ION sense feature. The average paerson doesn't have the ability to scan data, so they never know what's up.
To tell people "plugs are plugs" and to use whatever brand they want that the cross reference says will fit shows inexperience. Perfect example anyone can go to the store and see. Husqvarna string trimmers require a resistor type plug. Go down to Lowes, Home Depot, wherever and look at the E3 plug. Says it fits. But, it's not a resistor - look on the back of the package at the top corner in little print. When installed in small equipment like that, many times the ignition module freaks out from EMI and the things don't run, stall, won't rpm, etc. Then it comes in for repair, and it's because someone naively believed the cross reference. I could go on and on with real world examples from Harley and automotive where someone put in plugs that the cross reference says "fits" but they come in with performance issues and computer codes.
To tell people "plugs are plugs" and to use whatever brand they want that the cross reference says will fit shows inexperience. Perfect example anyone can go to the store and see. Husqvarna string trimmers require a resistor type plug. Go down to Lowes, Home Depot, wherever and look at the E3 plug. Says it fits. But, it's not a resistor - look on the back of the package at the top corner in little print. When installed in small equipment like that, many times the ignition module freaks out from EMI and the things don't run, stall, won't rpm, etc. Then it comes in for repair, and it's because someone naively believed the cross reference. I could go on and on with real world examples from Harley and automotive where someone put in plugs that the cross reference says "fits" but they come in with performance issues and computer codes.
Grand HDF Member
Joined: Sep 2017
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From: Dubuque, IA
You apparently missed the conversation I posted here from a Delphi tech/rep that put that nonsense about having to use the stock plugs or the ion sense would freak out to bed. It's designed to work across a wide range of resistance and I know you didn't just call me inexperienced, son. 
Every time someone says anything about running NGKs I hear the same thing. Nevermind there's probably as many running NGKs as there are the stock champions and have been for many moons.
Every time someone says anything about running NGKs I hear the same thing. Nevermind there's probably as many running NGKs as there are the stock champions and have been for many moons.
Last edited by 60Gunner; Oct 1, 2020 at 10:07 AM.
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Joined: May 2008
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From: South Carolina
Last edited by Dan89FLSTC; Oct 1, 2020 at 10:15 AM.
You apparently missed the conversation I posted here from a Delphi tech/rep that put that nonsense about having to use the stock plugs or the ion sense would freak out to bed. It's designed to work across a wide range of resistance and I know you didn't just call me inexperienced, son.
The information I am presenting is not to have an argument, it is to get factual information out there to people. The problem is that there is so much mis-information that gets reposted (many times unknowingly) that is persists.
Very recently I had a forum member with a shop in Florida contact me regarding bad results and erratic readings while mapping a bike on the dyno. Going to the basics we got to plugs. Turned out there were aftermarket plugs that an interchange said "fits" that were wreaking havoc with the ION sense.
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From: NorCal
Copy that!!!!! The indy I used 3 years ago talked me into NGK plug dcpr7e with out any problems... When installing new harley 6r12 plugs today, the NGK no.1 plug idle ring had sooty gas left behind on it, you could smell it.... Replaced plugs with 6r12's and when for a 4 mile jaunt...acceleration was smooth but idle was different... shot front cylinder intake with brake kleen and it killed the motor....Off to HD tomorrow for flanges and seals...Thanks for getting back to me....much appreciated...... Have a good night......And by the way, I researched using brake cleaner to find intake leak...not a good idea....I guess the burned fumes from the cleaner out the exhaust can be deadly....Live and learn
The resistor’s biggest job is to help provide a sharp, clean ‘pulse’ type spark. If the spark ‘dribbles’ across the gap in the beginning, it doesn’t light the fuel/air charge properly. If it dribbles at the end of the spark, it eats away at the spark plug electrodes and other ‘arc gap’ components in the ignition, shortening their useful life. The lowest spark plug resistance that seems to perform the task of chopping off the front and back “tails” of the spark is about 500 - 600 ohms. Fortunately, excessively low resistance is almost never a problem.
i hate champion with a passion, seen brand new out the box plugs not work. if they are mfg for hd, probably to hd spec's per application.
i hate champion with a passion, seen brand new out the box plugs not work. if they are mfg for hd, probably to hd spec's per application.
Last edited by Ed Ramberger; Oct 1, 2020 at 12:04 PM. Reason: Add RFI
Seasoned HDF Member
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champion is shinola! i am an industrial mechanic and when you have an engine down, oil companies do not like excuses, period.
i'll just throw two examples
1> waukesha 7042 not running right, altronic ignition monitor points to worn out plugs. install out the box 12 new 55 dollar a piece plugs and engine would not start much less run. did 12 plugs get dropped, hummmm, don't think so. put back old plugs, started and ran till we could get some more sent over. this time stitt's.
2> pulling a camper to florida, did a major tune up on the tow vehicle including new champions. well, made to florida but coming back, vehicle ran like shinola! the fuel mileage went down big time, at first thought it was bad gasoline. the plugs had 1500 miles on them. i made it back and started troubleshooting, absolutely nothing showed up. so for grins and giggles changed the plugs, low and behold, ran like a brand new machine.
only two examples out of many. i haven't bought a champion plug in probably 30 years, and guess what, never had a plug issue since then either.
champion has a history of shinola coming out the door when they have labor issues, probably why they are china made now.
that is very true mr. ed, but emf or rfi was not the issue brought up, it was resistance. the resistance is there to suppress ringing in the strike, if it wasn't for that, a coat hanger could be used.
all i said was that the low ohmage could be a design parameter since it does not take a high amount to help clean up the strike.
i'll just throw two examples
1> waukesha 7042 not running right, altronic ignition monitor points to worn out plugs. install out the box 12 new 55 dollar a piece plugs and engine would not start much less run. did 12 plugs get dropped, hummmm, don't think so. put back old plugs, started and ran till we could get some more sent over. this time stitt's.
2> pulling a camper to florida, did a major tune up on the tow vehicle including new champions. well, made to florida but coming back, vehicle ran like shinola! the fuel mileage went down big time, at first thought it was bad gasoline. the plugs had 1500 miles on them. i made it back and started troubleshooting, absolutely nothing showed up. so for grins and giggles changed the plugs, low and behold, ran like a brand new machine.
only two examples out of many. i haven't bought a champion plug in probably 30 years, and guess what, never had a plug issue since then either.
champion has a history of shinola coming out the door when they have labor issues, probably why they are china made now.
that is very true mr. ed, but emf or rfi was not the issue brought up, it was resistance. the resistance is there to suppress ringing in the strike, if it wasn't for that, a coat hanger could be used.
all i said was that the low ohmage could be a design parameter since it does not take a high amount to help clean up the strike.
Last edited by bustert; Oct 1, 2020 at 11:53 AM.
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Seasoned HDF Member
Joined: Aug 2008
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yep, industrial plugs can easily go over 100 bucks each, the very reason why champion was used. but if you have an engine down and production shut in, what will it be
1. high dollar plugs
2. thousands of dollars in lost production
not to mention pissed consumers because their gasoline price went up!
1. high dollar plugs
2. thousands of dollars in lost production
not to mention pissed consumers because their gasoline price went up!