Platinum and Iridium plugs will have a slightly better wear factor than copper core plugs will and they may light a little easier because of the finer electrodes and better conductivity.

"OHMS LAW" is tough to violate (path of least resistance)

Lets say the E3 plugs have 5 ground electrodes,the path is going to pick one(the easiest one to arc to).

Much better to make sure the ignition system is in good shape and the timing is correct.

Spark plug heat range is correct for the engine (fuel mix and compression enter into this) is important.

High ouput coils on a street bike are worthless unless the engine borders on a race engine,the coil only makes what the engine needs to light the plugs.

If the engine is lean it takes a little more if the engine is rich it takes a little less to start the fire,either way the power will be off

I happen to use NGK DCPR8EIX plugs but the DCPR7E plugs should work fine.

 

nope....

 

All this is great however, different plugs will produce a different output off the same ignition system, which can be read in KVA output on a scope. Just to play around a bit we took all sorts of plugs and put them into a Camaro Z28 when I was working for Chevrolet. The car required an AC R45TS plug but other manufacturers had there own plugs for that application. When we fired the engine it was quite clear not all plugs were the same and the AC plug far and away put out more on the KVA than the others. Nothing in the stock GM electronic ignition was changed, only the plugs.

I'm running 48/190 on an 04 1200 R model with a high flow and a Cycle Shack full system but I am -1 on the counter. The inner pipes stay a nice honeycomb and the SE triple platinum have been flawless in the last 3 years.

 

Each to their own, but I'm perfectly happy with my cheap HD 6R12 or Champion RA8HC (810's)..

Never had a problem with them on any of my Harley's, Spring, Summer, Fall, or Winter... They burn clean, don't carbon up, inside of the pipes is a nice light grey color, etc...

Used them for years and years, but what works for me might not be best for others.

 

The only advantage I can see that is supposed to be from the multi-gap plugs is when the gap of the least resistance gets carboned up or becomes more resistive for whatever reason, the spark will go to another gap. But, If the plug is getting carboned up, aren't all of the gaps getting carboned up at the same time? I think that shoots that theory...

 

Dont see the plugs making much difference all things being the same.
Heat Range,Plug Type and GAP.

Resistor vs Standard now thats a maybe
Gap also a maybe.


But to say the Delco R45TS will out KVA say a Champion RBL13Y or an NGK BPR5FS is iffy at best
Make it intertesting and throw in the Autolite 15

Put 2 in 1-2
2 in 3-4
2 in 5-6
2 in 7-8
Then look at the scope

 

I would agree with this entirely. There will be a nominal difference in KVA from plug to plug, even if same brand,heat range, and gap.
Id like to chime in here..being a Certified master tech for Diamler-Chrysler for 20 years, Ive picked up a thing or two about plugs...lol

I believe hollywood is buying into the platinum hype seen on sunday morning morothead shows. When a plug fires, there is a nominal exchange of metal between the electrode and strap. every time it fires. Although the exchange of metal is minimal, eventually over time the gap increases due to metal loss. This is more rapidly occurred with ferrous (iron based) and copper metals.
Platinum, on the other hand is non ferrous. When the plug fires, there is a minimal exchange or breakdown of metal and/or gap. This is the hype with the platinum plugs. An extended service interval is achieved, however, performance generally remains the same...
So if your looking for the longer service interval hollywood, yes...there are better plugs on the market. BUT...due to the ease of spark plug change in your twin, Its time beneficial to just utilize a copper core plug, Like the OE that came in your sled...

BTW, glad to be here guys...you all are inspirational and have given me wild ideas of my rides...

 

If anybody thinks this is a bunch of folks that don't understand all the physics and working of internal combustion engines, and HD motorcycles, you haven't read much here. Just that most of us don't see a big difference in plugs.

Even people that I know that build "Stock" race cars, will say all the crap about this plug and that plug is ..... well, just marketing crap. Just like the $500 HD tire air.

 

Hey guys, I've been searching threads on here for several hours and looks like you all could help. My bikes been running like crap, so here's the scoop on the scoot:
2008 Fatboy Stage 1 download w/ V&H bigshots and K&N filter.
8500 miles currently
The rear plug looks VERY light grey and the front looks OK in color but deposits on the base of the ground electrode. Exhaust is about the same in color. No pop on decel. Sluggish on accel, smooths out about mid throttle but seems to run hot. I run ethanol free 93 consistently.

So should I:
Be concerned i might have debri somewhere in the line since I painted the bike over the winter?
Consider a tune (if that is your thoughts, I will not bother you with it on this forum)?
Buy new plugs and not worry about it if it's running fine?
Go to the dealer and use my best tool - the checkbook.

Thanks.

 

I doubt you'll see any performance increase out of a nice plug with high KVA... Unless you've put a few grand into the motor and you've worked the heads to the extreme to promote close-to-perfect fuel atomization and even flame propigation then a higher KVA isn't going to burn much more fuel. Cylinder geometry can be everything for efficiency of fuel burn. And, on top of that, lots of Dyno time to work out a great fuel map (or perfect jetting for carb's) and getting the timing just right would be required too... Besides, we're talking standard Harley motors here - definitley not the most efficient engine on the planet... anyone that's ridin behind a buddy that hops on the throttle and catches the sweet smell of fuel he leaves behind can attest.

As for maintenance intervals, you should see longer life from the better plugs - platinum or iridium, so if you wanna spend the money, then go for it for that reason.

I say save the money for a couple of beers and sit back, stare at the chrome, relive the great memories on the bike, and plan the ones to come...