decel popping and plug gap?
Road Warrior
Joined: Feb 2006
Posts: 1,281
Likes: 8
From:
RE: decel popping and plug gap?
ORIGINAL: nickpipe
Well here are my 2 cents worth on the plug gap. If your plugs are under gapped the ignition wont build the right amount of voltage to fully fire and burn the fuel in the cylinder. The closer gap requires less voltage for the spark to jump the air gap. When your plugs are gapped correctly the coils have to build a higher voltage charge to jump the air gap resulting in a hotter spark thereby burning the fuel better in the cylinder. The pop in your pipes on decel is caused by raw fuel being dumped into your pipes and ignighting from the heat of the pipes.
Just one man's opinion, Are there any Guru's that can shed more light on this
Nick
Well here are my 2 cents worth on the plug gap. If your plugs are under gapped the ignition wont build the right amount of voltage to fully fire and burn the fuel in the cylinder. The closer gap requires less voltage for the spark to jump the air gap. When your plugs are gapped correctly the coils have to build a higher voltage charge to jump the air gap resulting in a hotter spark thereby burning the fuel better in the cylinder. The pop in your pipes on decel is caused by raw fuel being dumped into your pipes and ignighting from the heat of the pipes.
Just one man's opinion, Are there any Guru's that can shed more light on this
Nick
Proper gap of .040 ( larger than .020) will result in a hotter spark bridging the electrode to ground and a more complete burn.
4th Gear
Joined: Sep 2006
Posts: 8
Likes: 0
From:
RE: decel popping and plug gap?
Maybe I am wrong but if the mixture is too rich it could run better with wider gaps
on the spark plug so the pops are gone, but if the mixtures was fine the gaps would be good enough.
So isn't this a wrong way to beat the problem and could cause this other problems,
maybe a overheated engine?
on the spark plug so the pops are gone, but if the mixtures was fine the gaps would be good enough.
So isn't this a wrong way to beat the problem and could cause this other problems,
maybe a overheated engine?
Cruiser
Joined: Jun 2006
Posts: 163
Likes: 0
From:
RE: decel popping and plug gap?
Excellent point! I was thinking the same thing as I read the first post on this thread. Spark plug gap would have been the last thing I would have thought to check for decel popping as 99% of the time it's due to fuel/air mix problems. Tweaking the gap in the plug to treat a fuel/air combo out of whack seems like bad methodology without first checking fuel richness/leanness.
Sure the gap needs to be set to spec, but it is just illogical to look at gap as a remedy unless all else is tackled first. With reports of bikes coming from the factory off spec though, I will definitely go take a gander at my new bike's plugs. Plus, closing the gap could cover up a lean-ness issue-no? As would widening cause the opposite? Gonna have to look into this further......just seems a lil fishy.
Thread Starter
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Road Captain
Joined: Jul 2006
Posts: 667
Likes: 8
From:
RE: decel popping and plug gap?
Hey Guys
Been watching the thread....seems to have helped someone, glad for that. Interesting points though about other issues. all I can report at the present is that the scoot is still running like a champ....popping is gone and the temp is still running the same. About 1200 miles into the change now, hey.....worked for me.
I have wondered though, if it could have been possible that one of the plugs I removed was bad, possibly due to the gap....and the new plugs with the correct gap cured the probelm....
I did discuss it with my dealer, and had a dyno done as well.....for free by the way....and they said that everything was well within specs. ......sorry, I didnt keep anything to post here. However, the tech that did my dyno told me that he had heard of one other bike that suffered the problem I was having, and when the plugs were replaced with the proper gap it stopped the probelm.
I guess engines being what they are, they will all run a little different even though the settings may be the same.....maybe I just got lucky. Either way, Im still wearing a BIG smile.
Been watching the thread....seems to have helped someone, glad for that. Interesting points though about other issues. all I can report at the present is that the scoot is still running like a champ....popping is gone and the temp is still running the same. About 1200 miles into the change now, hey.....worked for me.
I have wondered though, if it could have been possible that one of the plugs I removed was bad, possibly due to the gap....and the new plugs with the correct gap cured the probelm....
I did discuss it with my dealer, and had a dyno done as well.....for free by the way....and they said that everything was well within specs. ......sorry, I didnt keep anything to post here. However, the tech that did my dyno told me that he had heard of one other bike that suffered the problem I was having, and when the plugs were replaced with the proper gap it stopped the probelm.
I guess engines being what they are, they will all run a little different even though the settings may be the same.....maybe I just got lucky. Either way, Im still wearing a BIG smile.
Advanced
Joined: Sep 2006
Posts: 98
Likes: 1
From:
RE: decel popping and plug gap?
Seems valid enough for me in some applications. Good luck
http://www.ngkntk.co.uk/technicaltips/sparkpluggap.asp
Firing End
Resistor Plugs
Spark Plug Gap
Tightening Torque
Corona Stain
Fouling Range
Pre-ignition range
Multi-ground
electrode
Always check that the spark plug gap is compatible with the engine manufacturers specification. A gap that is too small means that the spark duration will be very quick and the spark will be thin and weak. The consequences of this may be bad starting and high exhaust emission levels. This will result in an increase in fuel consumption. If the gap is set too large, the ignition system will not be able to cope with the demands and a misfire situation will occur. Some wide gap spark plugs have a longer ground electrode to accommodate a wide gap setting. These must be used where specified, as opening up a standard plug to a wider gap setting may result in the electrodes not running parallel to each other. This could result in abnormal and premature electrode wear.
http://www.ngkntk.co.uk/technicaltips/sparkpluggap.asp
Firing End
Resistor Plugs
Spark Plug Gap
Tightening Torque
Corona Stain
Fouling Range
Pre-ignition range
Multi-ground
electrode
Always check that the spark plug gap is compatible with the engine manufacturers specification. A gap that is too small means that the spark duration will be very quick and the spark will be thin and weak. The consequences of this may be bad starting and high exhaust emission levels. This will result in an increase in fuel consumption. If the gap is set too large, the ignition system will not be able to cope with the demands and a misfire situation will occur. Some wide gap spark plugs have a longer ground electrode to accommodate a wide gap setting. These must be used where specified, as opening up a standard plug to a wider gap setting may result in the electrodes not running parallel to each other. This could result in abnormal and premature electrode wear.
4th Gear
Joined: Sep 2006
Posts: 8
Likes: 0
From:
RE: decel popping and plug gap?
Just what I thought, you're curing the problem with the pops but maybe in some cases
this could do damage. If not it's an excelent and easy way to speed up the engine;
just use a richer mixture and widen those gaps till 1.00 LOL
PS do at own risk...
this could do damage. If not it's an excelent and easy way to speed up the engine;
just use a richer mixture and widen those gaps till 1.00 LOL
PS do at own risk...
Road Master
Joined: Mar 2005
Posts: 878
Likes: 0
From: Cistern,Tx
RE: decel popping and plug gap?
Last week I was talking to George at Dobeck Perf. I have a DFO on and had it setup where it was running great, getting good mpg, no popping. I put Fullsac true dual pipe on and now it started popping on decel. Talked to George and I think the first thing he asked me about was if the plugs were gapped right. I did the 10000 on it and had put new plugs in. DUH it did not dawn on me when he asked me that. He told me some settings to try and it has improved the popping but not elimanted it so I am getting off my **** and go check the gap on the plugs.
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Joe Kucinski
Cruiser
Joined: Apr 2006
Posts: 182
Likes: 0
From:
RE: decel popping and plug gap?
Good points guys,but per the first qoute,he is setting the gaps at the manuf.'s specified gap so no chance of doing any harm.
ORIGINAL: glide
Sounds like a winner to me
Proper gap of .040 ( larger than .020) will result in a hotter spark bridging the electrode to ground and a more complete burn.
ORIGINAL: nickpipe
Well here are my 2 cents worth on the plug gap. If your plugs are under gapped the ignition wont build the right amount of voltage to fully fire and burn the fuel in the cylinder. The closer gap requires less voltage for the spark to jump the air gap. When your plugs are gapped correctly the coils have to build a higher voltage charge to jump the air gap resulting in a hotter spark thereby burning the fuel better in the cylinder. The pop in your pipes on decel is caused by raw fuel being dumped into your pipes and ignighting from the heat of the pipes.
Just one man's opinion, Are there any Guru's that can shed more light on this
Nick
Well here are my 2 cents worth on the plug gap. If your plugs are under gapped the ignition wont build the right amount of voltage to fully fire and burn the fuel in the cylinder. The closer gap requires less voltage for the spark to jump the air gap. When your plugs are gapped correctly the coils have to build a higher voltage charge to jump the air gap resulting in a hotter spark thereby burning the fuel better in the cylinder. The pop in your pipes on decel is caused by raw fuel being dumped into your pipes and ignighting from the heat of the pipes.
Just one man's opinion, Are there any Guru's that can shed more light on this
Nick
Proper gap of .040 ( larger than .020) will result in a hotter spark bridging the electrode to ground and a more complete burn.
Tourer
Joined: May 2006
Posts: 319
Likes: 0
From: Cape Coral, FL
RE: decel popping and plug gap?
It is nomal to have a small range for spark gap (Like .038-.042). I have always gapped towad the smaller side (.038) knowing with some miles and normal wear on the electrode, the gap will soon widen.