Spark Plugs, is there a difference?
Seasoned HDF Member
Joined: Mar 2010
Posts: 38,593
Likes: 6,435
From: Honah Lee
Cross reference
Cross reference. Also not sure if ECM would measure resistance of a spark plug. How a Knock Sensor Work.
It detects the slightest noise in the engine and picks up on the "knock" of pre-ignition and sends the information to the ECM (Electronic Control Module). This ping is caused when the mixture of air and gas does not burn smoothly. This sensor is usually mounted on the cylinder and is connected to the ECM. When knocking or pinging is detected, the sensor sends a signal to the ECM, and this in turn retards the engine spark timing at two degree intervals until it has corrected the issue. The sensor's microphone is so sensitive it picks up the knocking when the human ear cannot detect it. It will hear the slightest ping even when the engine is at its top speed. A floating valve or bad lifter can trigger it.
Last edited by Jackie Paper; Sep 14, 2018 at 10:27 AM.
Seasoned HDF Member
Joined: Oct 2006
Posts: 5,977
Likes: 85
From: Nevada
I agree that Autolite plugs are very good.
Tourer
Joined: Aug 2008
Posts: 270
Likes: 1
6th Gear
Joined: Aug 2020
Posts: 11
Likes: 2
From: Chitown
There is a difference in material and in some applications certain plugs work better than others. The job of your plugs, wires, coil is to eliminate misfires. The only reason to run iridium, unobtainium, etc is they last longer. Run a fine wire gold tip in the proper heat range and index them and your bike will perform better.
Stellar HDF Member
Joined: Jun 2019
Posts: 3,269
Likes: 3,715
From: oxford, pa
There is a difference in material and in some applications certain plugs work better than others. The job of your plugs, wires, coil is to eliminate misfires. The only reason to run iridium, unobtainium, etc is they last longer. Run a fine wire gold tip in the proper heat range and index them and your bike will perform better.
Road Warrior
Joined: Feb 2017
Posts: 1,528
Likes: 647
From: Saint Charles, Missouri
Now, if they made a 2 amp coil for HD's you would have all the spark energy that you could use and you couldn't develop enough cylinder pressure to blow out the spark. It could also seriously hurt you.
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
