Autolite AP3923 Spark Plugs replaced with E3.64 Spark Plugs
 

Some of you may already be familiar with E3 Spark Plugs. I was tipped off by a Riding Buddy who put a pair in his Moto Guzzi Stone. He kept saying how much better the Goose runs with them. I asked specifically how well it starts in colder temps...he said there is a definite improvement in cold weather starting using the E3 Spark Plugs.

Well that was enough of a testimony for me to give them a try. I removed the Autolite AP3923 Spark Plugs during my Spring Tune-up and replaced them with new E3.64 Spark Plugs. I must confess that the shape of the Ground Electrode has a very strong "Snake Oilish" look to it. I bought the pair at O’Reilly Auto Parts for $12.94 including tax.

You can review the "Scientific Proof" on their website here (E3 Spark Plugs).

My experince is at a total of 87 miles now and includes a low ambient temp of ~33°F and high ambient temp of ~65°F. The engine starts well, doesn't miss a beat at low idle. In general I want to say it runs really well with the E3s but I'm leary of any seat of the pants "feel" versus a dyno run - which I do not plan to do.

A couple of concerns:

1) The Gap on these Plugs is much wider at 0.049” (1.245mm) versus stock setting of 0.032” (0.8128mm) and can’t be adjusted.

2) The Ground Electrode extends into the cylinder ~1.2mm deeper than the Autolite AP3923. Piston contact was a scary thought!:eek:

Here's a couple pics:
http://forums.pelicanparts.com/uploa...1271635882.jpg

http://forums.pelicanparts.com/uploa...1271635909.jpg

New E3.64 and old Autolite AP3923 Spark Plugs:
http://forums.pelicanparts.com/uploa...1271635954.jpg

subscribing

Pretty Buck Rogers looking, let us know how they last after 10k hard miles.

Different plugs are a cheap, easy mod to make and it's interesting to see the different concepts.
There seems to be two basic approaches: Multi-grounds or precious metal electrodes although sometimes they're combined. There have been numerous threads on the topic but I don't think you can alter the fact that by introducing more metal (multi-electrodes), especially with higher compression, you run the risk of pinging or detonation when runnning hard and/or less than ideal fuel out on the road. Conversely, precious metal plugs, like iridiums with a single electrode, can provide longer life through the inate hardness of the material and as a result, the electrodes can be made smaller which means less resistance and improved ignition.

Dang....I understand everything you said so maybe there's hope after all! :D



And it makes sense which is why I've pretty much stuck to single electrode precious metal.

Did Ken just say "bigger may not be better"? And, there should be more resistance to buying this new fishing lure.

Hey! Turn that computer off. Don't you have somewhere to go? :D:D

You could use another washer on the plug to get the same reach. I'll stick with the 3923.

Bigger gap means the high voltage system has to work at a higher voltage and that can lead to leakage and conducting paths forming. Bad idea. There might be a tiny additional spark discharge delay and that might feel smoother like any spark retard.

There's only one spark and adding all that metal shroud adds nothing to the spark.

More snake-oil.

Thanks for your lengthy reply Roger.:D

I'll be honest with you. Multi-ground, multiple surface grounds, etc. are more marketing than fact. Someone previously mentioned that a plug only produces one spark per cycle. That's 100% correct whether you have 1, 2, 3, 4 or 3 sided grounds. The impact of additonal grounding surfaces is dubious at best and snake oil at worst. Conversely, the lower resistance of smaller (.6mm to .4mm) precious metal electrodes is proven. Youz make ur' choice and payz ur' money.

Well alrighty then
 

since I'm about to do the 30,000 mile service on my R12S, which plugs should I use? Ken? Got a precious metal single electrode recommendation for both plugs?

There's lot's of good iridiums available, Autolite, ND (Nippon Denso) but my personal favorite is NGK Iridiums-great value and great life, nice quality plating and IMO, improved idle and starting:
http://forums.pelicanparts.com/uploa...1271727757.jpg

Oh, and on the R12S, all 4 plugs are the same:

NGK Iridium DCPR8EIX

Got it.
Thanks.

After a nice trip to Missouri and Arkansas last month and I gotta say the E3 Spark Plugs have sold me. There's something going on with the hole in the bottom of the ground electrode and it's positive effect on Flame Front Propagation - well that's my theory anyway.

Hard/aggressive riding up and down those hills and around all those curves...she ran strong the whole time in the upper 90s temps - never a pinging sound either. She also starts up real fast and idles like a purring kitten.

I got just under 44 MPG over the 1600 mile trip which is 2 MPG better than my worst consumption rate using Autolite 3923 Plugs. Total miles since the change to E3.64 Plugs is now 2851.

Here's a few pics from our trip.

Here's our Waitress at the "Little Cafe" next the the BIG GUN SHOP in Arcadia, MO:
http://forums.pelicanparts.com/uploa...1278556068.jpg

Here we are after one of our Guys low-sided his 650 V-Strom on a sharp left - fortunately his riding gear held him in good stead:
http://forums.pelicanparts.com/uploa...1278556259.jpg

After recovering from the low-side and a bite to eat in Norfork AR, we went onto AR-341 South - lotta fun that road!:
http://forums.pelicanparts.com/uploa...1278556393.jpg

A day later our Guy on the Bandit 1200 had a rear wheel bearing failure - took us half a day to chase down a new Bearing and Tools to fix it with:
http://forums.pelicanparts.com/uploa...1278556533.jpg

Oh and by the way, don't test ride your Buddy's FJR1300 - just don't I'm saying!
http://forums.pelicanparts.com/uploa...1278556890.jpg

E3.64 Spark Plug after 6,529 miles
 

I pulled out the E3.64 Spark Plugs from my '99 R1100S Single Spark after 6,529 miles and they look very good. I'm going to put them back in for some more miles.

http://forums.pelicanparts.com/uploa...1306620648.jpg

plugs do give an spark for fuel to ignite, different plugs... dont believe they can make so much of a difference as how much ignite fuel?
The only reason I personally go for Iridiums (NGK) is that they last forever, have less of contact surface for potential flooding. My other bike is turning my 30k on them- checked, looked at, wire (soft) brushed two(of 4)- put back in and dont believe will be getting them out soon

You never gave closure to your transmission thread Dan.