I keep replacing spark plugs?
Thread Starter
|
5th Gear
Joined: Jun 2020
Posts: 9
Likes: 1
From: Newcastle
I keep replacing spark plugs?
After a 1000 mile ride a year back, i parked up my 82 FLT and didnt ride it for a while for various reasons. When I did start it up, there was much backfiring and general rough running, definartely not ridable. So i initially put it down to bad fuel, so I pulled the Super E fuel bowl and cleaned jets, accelerater pump etc in my Ultarsonic Cleaner. All good, reassembled, but running just the same, so I changed out to a pre gapped new set of HD 5R6A plugs. Once done, all was sweet, running much better. I did a tune as best as I could on the carb, and went off for a 100 mile ride, no drama. I parked up for 24 Hours and returned home. Starts great, idles great, needed to idle for 10 min in a traffic jam straight up, and then she started running rough again. So I decided to change plugs on the side of the road, and all good again, rode home just fine.
So the plugs were pulled when i got home, and they looked the same as the others, pretty black, not oily. So rich, i guess. I cleaned up the previously replaced plugs and put them back in and they were chit, ran like a bitch, backfiring again.
So any clues as to why the plugs have been toasted? I get it that it may have been runing rich, but why are the plugs then unusable?
Dave
So the plugs were pulled when i got home, and they looked the same as the others, pretty black, not oily. So rich, i guess. I cleaned up the previously replaced plugs and put them back in and they were chit, ran like a bitch, backfiring again.
So any clues as to why the plugs have been toasted? I get it that it may have been runing rich, but why are the plugs then unusable?
Dave
Seasoned HDF Member
Joined: Aug 2006
Posts: 24,526
Likes: 30,842
From: Pennsylvania
Harley OEM Plugs for an 82 Shovel is 5RL, 5R6AG, or 5R6APP may want to try a different plug than 5R6A. See Chart: http://www.harley-performance.com/ha...park-plug.html
Grand HDF Member
Joined: Aug 2018
Posts: 4,126
Likes: 2,117
From: W. MI.
Did you change jets in the carb? Any motor mods at all? For me, I threw HD plugs away a long time ago. I went to Autolites and have never had an issue. My shovel runs best on them. I've also found that my bikes run best at a plug gap of .041. To each their own, you have some good advice above.
Cruiser
Joined: May 2017
Posts: 240
Likes: 90
From: Pittsburgh
Trending Topics
Thread Starter
|
5th Gear
Joined: Jun 2020
Posts: 9
Likes: 1
From: Newcastle
Ok, thanks fellas, I have some Autolites on the way. Though I still dont understand why if I clean up the previously fouled plugs, why they are now useless?
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
Seasoned HDF Member
Joined: Nov 2006
Posts: 12,878
Likes: 5,449
From: la la land jerzey
Because they dont make things to work forever anymore
you did not post what jets you were using a 70 main and 295 intermediate is what we would expect to find in it
while a agree that the acc pump could be rich and over squirting the engine - i tend to see this as a over rich jetting issue - coming if a trip and having a fouled plug unless it was stop and go
you did not post what jets you were using a 70 main and 295 intermediate is what we would expect to find in it
while a agree that the acc pump could be rich and over squirting the engine - i tend to see this as a over rich jetting issue - coming if a trip and having a fouled plug unless it was stop and go
Tourer
Joined: Sep 2020
Posts: 487
Likes: 289
From: Northern MN
He road a thousand miles last year and the bike is fouled up this year.
So I surmise it’s not the plugs that are the cause. The plugs are the effect of another cause. If it were my bike, I would kick it. Then I would watch a YouTube video about the carb. Setting the fuel ratio, and all of that.
I’m not an expert but I did rebuild my carb last year and treated it as a new carb.
I don’t think your plugs are the problem. Too much fuel, timing. Something is fouling the plugs.
Tom
So I surmise it’s not the plugs that are the cause. The plugs are the effect of another cause. If it were my bike, I would kick it. Then I would watch a YouTube video about the carb. Setting the fuel ratio, and all of that.
I’m not an expert but I did rebuild my carb last year and treated it as a new carb.
I don’t think your plugs are the problem. Too much fuel, timing. Something is fouling the plugs.
Tom