strange spark plug color
Grand HDF Member
Joined: May 2008
Posts: 4,325
Likes: 3,573
From: Picayune, Ms.
I believe you mentioned that you are running dual fire system.
Is the proper spark plug wire connect to the correct spark plug?
Does the black appear to be glazed, powdery, wet, or oily?
The white appears to white, ie running lean. Is it glazed over? If it is then your problem could be an air leak in the rear cylinder, which is over compensated for at the carb(tuned rich) there fore making the front cylinder run rich.
Is the proper spark plug wire connect to the correct spark plug?
Does the black appear to be glazed, powdery, wet, or oily?
The white appears to white, ie running lean. Is it glazed over? If it is then your problem could be an air leak in the rear cylinder, which is over compensated for at the carb(tuned rich) there fore making the front cylinder run rich.
Thread Starter
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Tourer
Joined: Oct 2010
Posts: 310
Likes: 1
I gonna explain this the best I can about where the timing plate is .Now going off the graduated lines going from 7:00 to about 4:00 on the bottom of the plate.I marked the factory setting on the last line to the right with a scribed line in the nose cone so I know where it was.when I put it back together I used the same scribed line.If I was to turn the plate more adv. going clockwise like the arrow points I have about a 1/16 of travel left in the plate before its at full adv. measuring from my scribed line to the last line to the right on the graduated lines with the plate at full adv. .I don't know if I'm close or if the timing is way too adv.This the way the factory set it up or somebody tampered with it and re riveted the cover on the nose cone like factory.
Thread Starter
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Tourer
Joined: Oct 2010
Posts: 310
Likes: 1
I believe you mentioned that you are running dual fire system.
Is the proper spark plug wire connect to the correct spark plug?
Does the black appear to be glazed, powdery, wet, or oily?
The white appears to white, ie running lean. Is it glazed over? If it is then your problem could be an air leak in the rear cylinder, which is over compensated for at the carb(tuned rich) there fore making the front cylinder run rich.
Is the proper spark plug wire connect to the correct spark plug?
Does the black appear to be glazed, powdery, wet, or oily?
The white appears to white, ie running lean. Is it glazed over? If it is then your problem could be an air leak in the rear cylinder, which is over compensated for at the carb(tuned rich) there fore making the front cylinder run rich.
Thread Starter
|
Tourer
Joined: Oct 2010
Posts: 310
Likes: 1
With the ngk bpr5es 11 plugs I've been running the part where the arm comes out of the body I put a sharpie mark on the upper ceramic.The front is at 12:00 with the opening facing the primary and the rear is at 3:00 with the opening facing the intake valve.
with champion rn12yc plugs in it. the front is at 9:00 so the opening is facing the intake valve and the rear is at 11:00 so the opening is facing the primary.
with champion rn12yc plugs in it. the front is at 9:00 so the opening is facing the intake valve and the rear is at 11:00 so the opening is facing the primary.
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Seasoned HDF Member
Joined: Dec 2010
Posts: 7,736
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From: Coromandel Peninsula New Zealand
I keep asking if you have checked the ign timing yet....with a strobe? Your backplate position suggest that it might be a good idea....indexing the plug gap won't make heap of difference....
Grand HDF Member
Joined: May 2008
Posts: 4,325
Likes: 3,573
From: Picayune, Ms.
HD's normally run the other way round, rich rear cylinder, lean front cylinder.
I agree with Spanner, you need to check the timing. While you have the nose cone open check and make sure the trigger is indexed correctly and tight. Get another trigger and compare the two, or just try running a different trigger. I had one drilled off center once and it was a nite mare figuring that out.
Make sure that you are using the correct timing marks on the flywheel, HD had several different marks and used them in the same year engines.
Are pushrods adjustable?
Popping out of exhaust usually means rich condition, fuel is burning in the exhaust pipe, since both plugs fire at the same time the one firing on exhaust is igniting excessive fuel thus popping out the exhaust. This I believe to be the front cylinder.
When you accelerate the fuel is forced into the rear cylinder(Newton and all that), thus making it run normal, at cruse < 40 the fuel distribution is totally dependent on the carb/intake system to supply equal fuel to the cylinders. I believe this is where you will find the culprit. At 40mph you are still running on the idle circuit of the carb, you need somewhere around 60mph to get to the main jet fuel circuit.
What really worries me is the white/lean plug. You could actually start melting pistons if running hot. Beware of a silver metal flake looking insulator.
I agree with Spanner, you need to check the timing. While you have the nose cone open check and make sure the trigger is indexed correctly and tight. Get another trigger and compare the two, or just try running a different trigger. I had one drilled off center once and it was a nite mare figuring that out.
Make sure that you are using the correct timing marks on the flywheel, HD had several different marks and used them in the same year engines.
Are pushrods adjustable?
Popping out of exhaust usually means rich condition, fuel is burning in the exhaust pipe, since both plugs fire at the same time the one firing on exhaust is igniting excessive fuel thus popping out the exhaust. This I believe to be the front cylinder.
When you accelerate the fuel is forced into the rear cylinder(Newton and all that), thus making it run normal, at cruse < 40 the fuel distribution is totally dependent on the carb/intake system to supply equal fuel to the cylinders. I believe this is where you will find the culprit. At 40mph you are still running on the idle circuit of the carb, you need somewhere around 60mph to get to the main jet fuel circuit.
What really worries me is the white/lean plug. You could actually start melting pistons if running hot. Beware of a silver metal flake looking insulator.