Spark Plugs
Thread Starter
|
Advanced
Joined: Jul 2009
Posts: 77
Likes: 1
From: ohio , 30% of the available sunshine state
Spark Plugs
Changed old plugs (screaming eagle ) with new plugs (screaming eagle) , bike runs like crap. Stumbling and throttle response is worst. Put old plugs back in and runs great. Repeat and same crappy results. Bought new plugs and same thing. Any ideas? Possible tune (fp3) is for old plugs lol? Gap for plugs looks to be same. Im baffled 
Grand HDF Member
Joined: Nov 2004
Posts: 3,917
Likes: 184
From:
Changed old plugs (screaming eagle ) with new plugs (screaming eagle) , bike runs like crap. Stumbling and throttle response is worst. Put old plugs back in and runs great. Repeat and same crappy results. Bought new plugs and same thing. Any ideas? Possible tune (fp3) is for old plugs lol? Gap for plugs looks to be same. Im baffled
Last edited by Tn.Heritage; Aug 15, 2018 at 02:17 PM.
Elite HDF Member
Joined: Jun 2007
Posts: 4,867
Likes: 268
From: People's Republic of Boulder Colorado
Changed old plugs (screaming eagle ) with new plugs (screaming eagle) , bike runs like crap. Stumbling and throttle response is worst. Put old plugs back in and runs great. Repeat and same crappy results. Bought new plugs and same thing. Any ideas? Possible tune (fp3) is for old plugs lol? Gap for plugs looks to be same. Im baffled
Last edited by jpooch00; Aug 16, 2018 at 07:16 AM.
Trending Topics
Elite HDF Member
Joined: May 2007
Posts: 4,452
Likes: 798
From: Bear Flag, lower end
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
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Road Warrior
Joined: Mar 2014
Posts: 1,973
Likes: 158
From: East Coast
Who would ever trust the gap out of the box, I am not saying the OP did, but you stated looks to be the same, gap them with a feely gauge.
If you hadn't tried a second pair of new plugs i'd thought it could have been cracked insulator or other plug issue.
First double check the gap.
If you hadn't tried a second pair of new plugs i'd thought it could have been cracked insulator or other plug issue.
First double check the gap.
Grand HDF Member
Joined: Aug 2014
Posts: 4,726
Likes: 1,787
From: Toledo ohio
You could ohm out the plugs, tip to tip. compare to the old ones, maybe the parts store got a bad batch. Where did you get the plugs from? If you got them from the internet, they could be knockoffs made on the Ho Chi Mihn trail .