Author Topic: Spark Plugs  (Read 5083 times)

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Sharc

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Spark Plugs
« on: August 19, 2003, 07:53:27 AM »
Anybody use BR9's...? The 2002 owners manual reccommends BR8EG. Somewhere I read Team Green reccommends BR9EG's....Anybody running those...?

 :twisted: Thanks :twisted:

Rick

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Spark Plugs
« Reply #1 on: August 19, 2003, 08:36:17 AM »
Nope.  I have run the BR8EVX for several years.  I did try an EG plug once, and it fouled.

Rick

Offline Paul

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« Reply #2 on: August 19, 2003, 09:13:52 AM »
I run the BR7EVX and it's been a first or second kick starter for 18 months. I have a spare in the airbox but haven't had to use it yet. Keep in mind the BR7EVX is a step hotter plug than the stocker.

Biggreenmonster

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Spark Plugs
« Reply #3 on: August 20, 2003, 12:26:38 AM »
I run the Split fire SF406C for over a year and its been a great plug.I can tell a little better throttle response from these plugs.Give one a try and you will see what i mean.I know alot of you run ngk but at the high price from my local dealer and not being able to get a the plug i want from a auto parts store i buy them in bulk from Dennis Kirk.A 4 pack is still in my tool box and i love them.Only my preference.

Sharc

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Spark Plugs
« Reply #4 on: August 20, 2003, 05:25:08 AM »
Speaking of hotter plugs, can someone please explain the hotter plug vs. colder....? Seems like the hotter the plug the hotter the spark the better the fuel burn, but I know its not that simple....

Thanks

Hogwylde

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Spark Plugs
« Reply #5 on: August 20, 2003, 10:29:17 AM »
A hotter or colder plug has nothing to do with how "hot" the spark is.  That is a function of your ignition system only.

Sparkplugs have the nose of the center electrode sticking out into the combustion chamber. How long this center electrode (and center insulator) are in relation to the outer shell determines how fast (or slow) it transfers the heat to the cylinder head.  With a long path for the heat to flow to the heat (hotter plug) it takes longer for the heat to transfer and the center electrode tends to run at a higher temperature.  With a short transfer path for the heat to the head (colder plug), the heat flows to the head quicker and runs cooler.

Now then....how do you know if you need a hotter or colder plug?  It's a matter of reading your plugs and a function of what kind of riding you do.  Sustained high speed riding puts LOTS of heat into your combustion chamber.  This MAY necessitate a cooler plug to avoid overheating the electrode and causing pre-ignition.  Running 1st, 2nd gears lugging thru woods and hardly ever getting on the pipe MAY necessitate a hotter plug to keep the electrode temp up high enough to burn off deposits and keep from fouling.

This is a very simplified explination.  Go to most major spark plug manufactures and you can get detailed drawings and explanations about spark plug heat ranges.

Sharc

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Spark Plugs
« Reply #6 on: August 21, 2003, 04:50:47 AM »
Thanks Hogwylde. Great info. I found this at NGK.com:

The term "spark plug heat range" refers to the speed with which the plug can transfer heat from the combustion chamber to the engine head. Whether the plug is to be installed in a boat, lawnmower, or racecar, it has been found the optimum combustion chamber temperature for gasoline engines is between 500?C?850?C. When it is within that range it is cool enough to avoid pre-ignition and plug tip overheating (which can cause engine damage), while still hot enough to burn off combustion deposits which cause fouling.

The spark plug can help maintain the optimum combustion chamber temperature. The primary method used to do this is by altering the internal length of the core nose, in addition, the alloy compositions in the electrodes can be changed. This means you may not be able to visually tell a difference between heat ranges. When a spark plug is referred to as a ?cold plug?, it is one that transfers heat rapidly from the firing tip into the engine head, which keeps the firing tip cooler. A ?hot plug? has a much slower rate of heat transfer, which keeps the firing tip hotter.

In identical spark plug types, the difference from one full heat range to the next is the ability to remove 70?C to 100?C from the combustion chamber. The heat range numbers used by spark plug manufacturers are not universal, by that we mean, a 10 heat range in Champion is not the same as a 10 heat range in NGK nor the same in Autolite. Some manufacturers numbering systems are opposite the other, for domestic manufacturers (Champion, Autolite, Splitfire), the higher the number, the hotter the plug. For Japanese manufacturers (NGK, Denso), the higher the number, the colder the plug. When making spark plug heat range changes, it is better to err on the side of too cold a plug. The worst thing that can happen from too cold a plug is a fouled spark plug, too hot a spark plug can cause severe engine damage

Also this about their Iridium spark plugs BR8EIX:

NGK iridium plugs represent the ultimate evolution of spark plug technology and performance. The iridium center electrode is both stronger and harder than platinum. This allows NGK engineers to design an ultra-fine (0.6mm) center electrode reducing the voltage requirement for spark. This allows for a brighter, stronger spark from your existing ignition system. The ground electrode has a tapered cut at the firing end which reduces quenching for better flame core growth and increased ignitability. The combination of fine wire center electrode and tapered cut ground will increase performance, improve acceleration, and fuel efficiency.

Too much info, but interesting.

Sharc :lol:

Rick

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Spark Plugs
« Reply #7 on: August 21, 2003, 05:48:24 AM »
I tested the BR8EIX in the same evironmental conditions (temperature, terrain, fuel, ratio, etc) and motor tuning as the BR8EVX, and found the Iridium more prone to fouling.  (Not sure why, as I am just a dumb accountant.)  As a result, I stayed with the BR8EVX plug in my bike, as I really did not want to start over and tuning for a different plug.

Just my $.02.

Rick

Offline Paul

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« Reply #8 on: August 23, 2003, 06:01:28 AM »

teamgreen500

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Spark Plugs
« Reply #9 on: September 06, 2003, 03:35:18 PM »
B9EVX is what The guys at Kawi put in my bikes for the Best in the Desert series. Actually, I've never had one fail on my trail bikes for that matter.

I've seen some plugs from NGK that just read E-9 or E-10 also used. The bikes don't seem to run any different.

Appaerantly the "R" plugs aren't a neccessity OR our ignitions aren't fragile like, oh, I don't know...maybe...HONDA's!

My motors are Pro-Circuit Top-end/split and I run P/C "MX500" and FMF "Fatty" pipes with stock silencers and/or bolt-on/add-on sparkys (motor doesn't seem to notice 'em).

I run Maxima "SuperM" @ 40:1 with "76" 110 and "76" pump premium 50:50 (Trail bikes...which are really just retired race bikes). At the races I run whatever the Kawi guys are runnin'.

I've NEVER fouled a plug, even when I'm puttin' all day with kids on 50's and 110's and all that goo is dripin' outta my KIPS and my pipe/silencer joint.

I'll find out what my jetting is...I really don't know...but it's spot on for out here in the West. I know it's a 39 w/ some kind of different slide and needle.

Well, that's my $.02...

Manny

Offline KXcam22

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« Reply #10 on: November 16, 2003, 05:15:40 PM »
'92 K5: I have been running a BP8ES for the last 6 seasons.  Yes that is the protruded electrode "the P" type.  They run clean, a plug last a season and they are dirt cheap.  Usually first or second kick starts.  I typically have to order the plugs from a auto parts store. I run stock main with a 58 pilot and needle clip at the top position.