Spark Plug poll

[randy]

Following the "hot" spark vs. weak spark thread, which category do you fit into:

I really don't care about all this...
I buy the correct plug and just put them in...
I want the best performance out of the bike, although I only use it to ride to Walmart to buy beef jerky and tube socks.

[Ivan]

You forgot the option:

"Whatever I had laying around the shop"

[tarzan]

I install what the book calls for.My opinion is a spark is a spark is a spark......until you have no spark.Keep plugs that are in good condition and make sure there is good spark to it.

[yamahansolo]

what???


i bought one step hotter for winter riding... that is my option but it wasn't there...

[DGXSER]

Unless someone can tell me that I will see more than .2 MPG improvement or shave more than .01 off the 1/4 mile, or some other meaningful performance improvement on a 30 year old engine with basically stock components, I do not see the point in buying platinum plugs or trying to get the gap that fine tuned or dialing in the direction of the opening...etc. Just my $2 worth (inflation you know).

[John]

I use the NGK BP6ES and I gap them at .35. A slightly wider gap is supposed to make the coil fire at a higher voltage to over come the the increase in compression the 1179cc kit gives you. Remember the GM electronic ignitions from the mid 70's? I had a 75 Cutlass (Gutlass) 350 4bbl 155 HP. The gap was .080, and the voltage required to fire that gap was, what 80K volts? Even thought the compression wasn't very high on those cars, they needed to start the flame as hot as possible to ignite as much fuel as possible, and try to burn it all to extract all the power possible. That is if I remember correctly

[TopCatGr58]

What can I say?

I didn't like even paying the modest $ for the NGK's, and have actually had good luck with CHAMPIONs, have run them for many years in many vehicles. Just standard plugs, or copper core, but no platinums. I have a new set of hi perf coils with the MikesXS ones and they fire just fine with 0.35" gap, but I might try going up to .40"!?

Now I know Tod rides much farther than just to Walmart. I'm the one that puts less than 1500 miles a year on mine!! So...I have been known to replace them every few years just because of possibility of RUST!!
T.C.

[skids]

railroading the plugs thread

Since we are on the subject of plugs, Do you think that cold rating plugs can ruin the caps quicker than hot plugs? (forget the affects of the weather for a moment.) Cold plugs are said to transfer heat quicker and they obviously have a bigger annode. The heat would more easily transfer into the caps wouldn't they? Higher temperature at the connectors mean faster rate of caps wear???

[prometheus578]

Skids,

Cold plugs are said to transfer heat quicker and they obviously have a bigger annode.

Anode(the tip) size is the same... the size/length of the insulator is different

Heat range has to do with the temp of the spark plug's tip and insulator cone.
The porcelain insulator must get hot enough to burn off carbon and self clean, but not too hot to melt or glaze.
This is done by having a large cone(surface) or a smaller cone.
Larger cone gets exposed to more combustion heat, hence is hotter.
Now then...
This insulator cone is connected to the spark plug metal body. The spark plug's metal case is screwed in the head.
(Many members here are also screwed in the head, but that's a topic for another day)
Now, what happens is...
Spark plugs heat up. (due to combustion chamber temps)
The heat of the tip and insulator cone is transferred to the plug body... which in turn, is dissipated by the metal mass of the head.
Which means...
A shorter cone transfers the heat away to the head quickly and is known as a colder running plug.
A longer cone, (meaning more exposed porcelain before connecting to the plug's metal body...) retains more heat, hence a hotter running plug.

The temp. difference between one rating of plug to the next is about 50 degrees F.
As most of the heat is dissipated by the head... I doubt that there would be much difference in temps at the end where the spark plug cap sits.
I could be wrong...
I would research this for you, but "Dancing with the Stars" is on right now...

And another thing...
If you're used to running Champions in your car... where a higher number means a hotter plug, remember that for Japanese plugs (NGK, etc) a higher number means a colder plug.
Another interesting thing...
Those weasles at Champion used the exact same photos on their site that are used on the NGK site.
Funny... reading about Champion spark plus... and the picture on their site shows a plug with NGK printed on it.
Another reason to not run Champion.

[TADracer]

I voted the middle selection on the poll. BUT, having said all that I have made the determination (at least in my case) through some trial and error that the manufacturer's recommended type and heat range plug is best suited to my machine. Doesnt matter if NGK, champion or Joe's Special as long as the heat range is right the plugs work fine. Now, I do run my gap at .035" but I have Dynacoils and Accel 8.8mm wires which can easily handle that gap.

Platinum or other exotic metal types do not give me any noticable increase in performance or mileage but they do last longer. But then they cost twice as much. The standard NGK plugs last about 10,000 miles for me.

Concerning heat range, a colder plug does not mean it has a colder or weaker spark. It means it will transfer heat away from the combustion chamber faster and can be used to keep the combustion temperature at the correct level for good fuel mixture burn (which should be around 1,200 degrees). I ride year around and have found that switching one range hotter in the winter helps maintain the combustion temp when the outside air over the cooling fins is cold.

[madmax-im]

Normally just the reccommended plugs are in there...the last change was when I was at TC's this summer and we couldnt find the NGKs' so we went with the Champions....no issues whatsoever.On the Maxim total mileage is only 21621 over the past 26 years...so I prolly avg less miles per year on it than TC does on his bike

[Dan Hodges]

Platinum Spark Plugs

Platinum spark plugs will last longer than a conventional plug but they will not make any more horsepower. In the context of this discussion we are talking about a 4 cycle engine on pump gas, a two cycle engine or a 4 cycle engine on alcohol, nitrus, nitro/methane or spook gas would be different. Both NGK and Champion plugs are equally good as long as you use the correct plug and you can cross reference one to the other. The piston dome and combustion chamber design are the primary factors that determine what the length of the plugs nose should be and the compression, type of operation and ignition system capacity will determine the gap. The stock ignition system (coils) of the Eleven are more than sufficient for a 9,000 rpm motor with 10 to 1 compression however if you have a high compression motor you need more voltage at the plugs to light the fire. In a 13 to 1 compression race motor on gas you will need 40,000 volts with about 160 Millijoules/spark of energy output. In a stock motor more voltage (hotter coils) won't hurt but the more voltage you have the more prone to leakage the plug wires become and then you will need plug wires with better insulation. Spark plug wire design is a science into itself with MSD and Moroso making some of the best. Actually all of this stuff is academic because the bottom line is, on a stock motor the stock plugs with the factory recommended gap is the plan. If your jetting (AF-ratio) is screwed up you can compensate some for it by changing the heat range of the plugs but this is not kosher for several reasons. If you are doing high speed riding in the summer time, one step colder on the center two plugs won't hurt. The correct plug for the XS is a NGK BP6ES which has a 14mm shell, a 3/4" reach, a 13/16" hex and a projected type gap. The Champion equivelent is an N-10Y, N-9Y or N-8Y, an Autolite would be a #53 or #54 and an Accel plug would be a # 114 or 115. Plugs come in a multitude of sizes and heat ranges with the following gap styles, regular type, regular v-type, special v-type, retracted type, projected v-type and our's, the projected type which is offered in heat ranges from BP5ES to BP9ES with the smaller number being hotter. Oh yes, if you use a 39 mm intake valve in the XS head for increased flow you will be using a plug with a regular type gap..........why didn't Yamaha use a 12mm plug that would have afforded more room and made life easier and less complicated for fools such as myself who can't leave well enough alone. So much for spark plugs, I quit.

[Ivan]

(Many members here are also screwed in the head, but that's a topic for another day)

closely followed by:

but "Dancing with the Stars" is on right now...

hmmmm......

[Dan Hodges]

Who Knows

closely followed by:



hmmmm......

I'm not screwed up in the head, at least I don't think so

and I don't dance, on the ceiling or in the stars, as a matter of fact I don't even drink or smoke and so I must admit I'm at a loss on this one.

[Ivan]

Actually, Prom was the one I quoted there, sorry for the misunderstanding.

I just thought it was funny for someone to talk about people being screwed up in the head, and then saying they were going to watch dancing with the stars.

Once again my sense of humor is only funny to me. Maybe I should join Prom in watching DWTS.