Where to start looking..??
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Joined: Oct 2007
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From: Decatur, Alabama
carl
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Joined: Jul 2014
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From: Cental, MI
tho I generally use Autolite
Champions are very best at recovering after Fouling.
in this case however
something other than fuel and air is contaminating that combustion chamber
Seasoned HDF Member
Joined: Mar 2010
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From: Poolville
Seriously no plug is going to change what's going on in that front cylinder period. you either have a bad valve guide or seal sucking too much oil in.. Or your rings or something going on there or a broken ringland. A leak down test will confirm the rings.. there's a lot of oil getting into that cylinder and it's possible that you're sucking it through the carburetor but that would normally do both cylinders not just one so I would think that it's related specifically to the front cylinder..
Seriously no plug is going to change what's going on in that front cylinder period. you either have a bad valve guide or seal sucking too much oil in.. Or your rings or something going on there or a broken ringland. A leak down test will confirm the rings.. there's a lot of oil getting into that cylinder and it's possible that you're sucking it through the carburetor but that would normally do both cylinders not just one so I would think that it's related specifically to the front cylinder..
This isn't about the plugs.
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Grand HDF Member
Joined: Aug 2008
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From: Florida's gorgeous East coast
Thanks guys. The comments about the valves are what I was afraid of. In my original posting, I was just trying to describe the issues I felt when riding and get some idea of where to look. I failed to mention that the Champion plugs were installed by my local Independent shop when they did a top end on the motor last June. Appreciate the recommendations 'cause I think we're closing in on what might be going on. After pulling those Champions, I installed a pair of Bosch Platinum plugs I've had good experience with in the past. I've also run NGK Iridiums and love them, but they can be hard to find in this little town I live in.
I'm going to run the Bosch for a while then look at them after 500 mi. as suggested. (I usually replace my plugs a 5,000 mi intervals.)
If the issue persists, It will be time to pull the head off the front cylinder before whatever it is gets any worse.
I'm going to run the Bosch for a while then look at them after 500 mi. as suggested. (I usually replace my plugs a 5,000 mi intervals.)
If the issue persists, It will be time to pull the head off the front cylinder before whatever it is gets any worse.
Seasoned HDF Member
Joined: Jul 2014
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From: Cental, MI
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From: Poolville
So obviously more information is required.. How many miles ago did you have the top and refreshed and what was the extent of that? Did you have the cylinders bored and new pistons and rings or did you just have it honed with new or oversized rings and what about the heads what did you have done.. All this is pertinent because it's possible it wasn't broken in correctly or it wasn't assembled correctly.. also where are your breathers routed?
Tourer
Joined: Sep 2017
Posts: 280
Likes: 96
From: DFW Texas
Agree with above, leakdown / compression check, check ignition module.
Guides and/or seals likely.
One more thing to consider, there could be a leak on the intake manifold on the front cylinder, unlikely but always throwing out the strange ones.
Straight off a spark plug company site
Possible Causes: Oil leaks, poor fuel quality.
Guides and/or seals likely.
One more thing to consider, there could be a leak on the intake manifold on the front cylinder, unlikely but always throwing out the strange ones.
Straight off a spark plug company site
Deposits
Appearance & Symptoms: The electrodes—center and ground—are covered in an ashy coating. As a result of this masking of the electrodes, your engine may experience a misfire. This build-up of combustion deposits can eventually (but not usually) fill in the space between the two electrodes.Possible Causes: Oil leaks, poor fuel quality.
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