Reading my plugs
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,070
Likes: 2,115
From: Ohio
Probaly everyone gets tired of hearing me harping about a AFR reader system but here is a 100+ hp front plug @ 14.0 idle 13.8-1 at cruise and 13.2-1 WOT, timing mark is in the center bend of the strap where it belongs, just posting it for referance. Sorry for being so repetative on my views of tuning.
Note: that is never seize on the threads that every plug manufacturer says not to use. Won't put them back in without it
Note: that is never seize on the threads that every plug manufacturer says not to use. Won't put them back in without it
Last edited by 1997bagger; Jan 26, 2019 at 11:57 PM.
Road Captain
Joined: Aug 2012
Posts: 625
Likes: 102
From: New Albany, Ms.
Curious
Probaly everyone gets tired of hearing me harping about a AFR reader system but here is a 100+ hp front plug @ 14.0 idle 13.8-1 at cruise and 13.2-1 WOT, timing mark is in the center bend of the strap where it belongs, just posting it for referance. Sorry for being so repetative on my views of tuning.
Note: that is never seize on the threads that every plug manufacturer says not to use. Won't put them back in without it
Note: that is never seize on the threads that every plug manufacturer says not to use. Won't put them back in without it
Ride safe,
Harold
Road Captain
Joined: Aug 2012
Posts: 625
Likes: 102
From: New Albany, Ms.
Ride safe,
Harold
Road Warrior
Joined: Mar 2007
Posts: 1,959
Likes: 2
From: Florida
How are these?
My bike has been running crappy lately, cuts out now and then, slow to start. Do these plugs call for a richer environment? The rear (right) is brown only on one side, other side is white. Thanks.
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,070
Likes: 2,115
From: Ohio
As close to the exhaust port of the head as possible with easy access to get a O2 sensor in and out. EFI needs needs 2 ports, carb needs one and the rear cylinder can run hotter because of air flow is slightly blocked, the plug shown in the pic is off the front cylinder
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,070
Likes: 2,115
From: Ohio
Use the plug picture chart that was provided earlier and some reading material in the attachment below helps in reading plugs
http://www.4secondsflat.com/Spark_plug_reading.html
http://www.4secondsflat.com/Spark_plug_reading.html
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Road Captain
Joined: Aug 2012
Posts: 625
Likes: 102
From: New Albany, Ms.
As close to the exhaust port of the head as possible with easy access to get a O2 sensor in and out. EFI needs needs 2 ports, carb needs one and the rear cylinder can run hotter because of air flow is slightly blocked, the plug shown in the pic is off the front cylinder
Ride safe,
Harold
( And I assume when you get the air, fuel mixture where you wan't it, you take the sensor out & plug the hole)
Last edited by LowriderHarold; Apr 1, 2013 at 10:40 PM.
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,070
Likes: 2,115
From: Ohio
So, you drilled a hole , welded the nut for the sensor to screw in, your exhaust pipe, close to the exhaust port of your head, if I'm understanding you correctly. In my case , with a carb, I only need to do one.
Ride safe,
Harold
( And I assume when you get the air, fuel mixture where you wan't it, you take the sensor out & plug the hole)
Ride safe,
Harold
( And I assume when you get the air, fuel mixture where you wan't it, you take the sensor out & plug the hole)