Wildguzzi.com
General Category => General Discussion => Topic started by: adaven on October 02, 2022, 07:54:42 AM
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On my '73 Eldorado I heard pinging on acceleration.
When I inspected the plugs, they were white with carbon fouling on one side.
I replaced the springs on the advance.
I set the timing at the third mark from the left at about 2200 rpm. The pinging is gone and it runs great.
Now the plugs are slightly darker, but still carbon fouled towards the grounded electrode.
How do I read this?
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Without a picture, I would not put much stock in any advice you get from this post.
"White," Carbon fouling," and "slightly darker," are very subjective terms. It's like trying to describe the color blue without a picture.
This could rapidly turn into an "oil thread."
I've read a few articles (Kevin Cameron, Cook Neilson, etc, IIRC) over the years that the motorcycle manufacturers are very conservative in terms of putting spark plugs that are too cold in the bikes at the factory.
I've always had good results running plugs that are one, two, or even three "numbers" that are hotter than stock.
If the bike is running well, overthinking to find a "better solution" is often a self-inflicted punishment. The Justice of Physics!
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You're right I guess.
I'll take a spin out to the Slimey Crud today and see if I can get a picture to post.
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You're right I guess.
I'll take a spin out to the Slimey Crud today and see if I can get a picture to post.
:grin:
opinions vary tremendously.
Some say modern fuel additives make plug reading questionable. Then there is the variation in techniques, throttle chop, WFO, 3/4 throttle, 1/2 throttle, etc.
IMO, too hot and too cold are obvious. It all depends on what you are after. If you are going for the perfect tune, then... "Your bike will never run as well as Fred's bike!"
Phases of the moon, time of the month, etc. are all effects that come into play. :wink:
Always easier to change plug heat ranges than carb jetting, etc.
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Easy............... ....
(https://i.ibb.co/Bq57jwD/spark-plug-lean-rich-optimal-640x360.jpg) (https://ibb.co/Bq57jwD)
Paul B :boozing:
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(https://i.ibb.co/7Q5nypY/20221002-112644.jpg) (https://ibb.co/7Q5nypY)
Mine always seem to have this "shadow" on one side. I was under the assumption that it was cast by the center electrode and had something to do with either incoming fuel charge or flame wall propagation?
This image is V11. My T3 produces a similar shadow.
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[ I was under the assumption that it was cast by the center electrode and had something to do with either incoming fuel charge or flame wall propagation?
You're on the right track. Indexing the plug will help with that spot. Side ground electrode should face the intake valve. Open side towards exhaust valve. My$.02.
Paul B :boozing:
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IMO, it is always interesting to see where your brain goes first with limited information. No doubt due to the past experience of the individual.
Since I have no background information, when I hear pinging engine, my brain goes to fuel with too low an octane rating, before it goes to ignition timing that is too advanced.
Growing up in very rainy Upstate NY, engine misfiring or sputtering? My brain goes to water in the gas first. More than a couple of road trip have been saved by finding an auto parts store and dumping some dry gas into the tank.
Now that ignition systems are orders of magnitude better than they were in the 60's and 70's, it is easy to start thinking that the carb jetting needs changing when when the spark plugs looks too dark.
The following post from someone much smarter than me, a long time ago, in a galaxy far, far, away.... got me thinking about hotter than stock spark plugs. I'm glad I read it. I've been running hotter than stock plugs in a few engines ever since. I run CR7 plugs in the DR.
Today’s Dyno Project bike. Suzuki DR 650. Dead stock, 700 total miles. semi late model Suzuki DR 650 thing. Bad hesitation in lower RPMs but EGA says mixture is good, not perfect but completely safe, well on the rich side. Air cooled old farm implement engines like rich mixtures too. Guzzi Content -Ed
Engines pulls to redline well though. Clears its throat at about 5500 rpm and runs to the limiter up top.
Odd yes.
Remove spark plugs. Cross ND number with NGK number, since I actually know NGK coding very well.
10 heat range? That is a race cold plug...only really used in roadracing two strokes and some very hot high performance 4 cylinder bikes that see stupid rpm.
Installed a set of 8 range plugs, much hotter, much better for an air cooled, puss camshafted, low compression , low rpm somewhat rich running single cylinder engine...especially with dual C size 10mm spark plugs.
All better. The 10's were just staying too cold on the insulator at low rpms to self clean at all! I sent the bike back home with the guy. $5.41 cents to solve a problem plaguing the bike from new. The 10's stayed clean enough to run when they got smoking hot at higher rpms...but wide open at low rpm, not a chance. This made a 1 bhp gain everywhere ironically.
The dyno chart showed an effectively a 10 bhp gain in the zone where trouble was bad and 1 bhp up top. I was proud of this diagnosis...about 15 minutes start to finish...sweet!
The truly proper heat range for this bike and the owner's riding style is a 6...maybe a 7 if he rides more aggressively than he says he does. Says it is strictly a put around town real slow sort of bike?
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Here's what the plugs looked like when I got back from Pine Bluff:
(https://i.ibb.co/X8MpHSq/Spark-plug-2.jpg) (https://ibb.co/X8MpHSq)
They look similar to n330j's V11
I would switch the descriptions for "lean" and "optimal" on RinkRat's photo.
I was hoping for a brazilian tan on the plugs, but have essentially a holstein heifer, if you know what I mean.
On the other hand, maybe I am looking for problems where there aren't any, and I should just relax, eh?
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I think the Brazilian tan complexion has gone the way of tetraethyl lead additive (or so I've been told by Vintage BMW guys).
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Here's what the plugs looked like when I got back from Pine Bluff:
(https://i.ibb.co/X8MpHSq/Spark-plug-2.jpg) (https://ibb.co/X8MpHSq)
They look similar to n330j's V11
I would switch the descriptions for "lean" and "optimal" on RinkRat's photo.
I was hoping for a brazilian tan on the plugs, but have essentially a holstein heifer, if you know what I mean.
On the other hand, maybe I am looking for problems where there aren't any, and I should just relax, eh?
kinda of an awkward photo angle to see the insulator color...... But the color that I can see looks pretty good.
I'd say good nuff, but then pull them again after another 50-200 miles just for my own recreation.
"Brazilian Tan" sounds like a highly desired bottle of local moonshine, or maybe some other form of contraband.
I've never seen the flame front shadow on a two stroke plug, or on a plug pulled from a four valve four stroke. Seems more prominent on the two valve four strokes.
IIRC, spark plug indexing advice was to aim the ground electode away from the intake valve.
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Maybe it isn't a flame front shadow then, but a function of the fuel charge inlet or exhaust?
Two strokes tend to dump the fuel charge in over a wide arc due to mulriple side porting. 4 valve 4 strokes dump the fuel in over a larger arc then a 2 valve 4 stroke. Same with exhaust porting.
So the shadow might be a result of this single point cylinder inlet and outlet that is unique to a two valve, four stroke engine.
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Easy............... ....
(https://i.ibb.co/Bq57jwD/spark-plug-lean-rich-optimal-640x360.jpg) (https://ibb.co/Bq57jwD)
Paul B :boozing:
Wait... Aren't the plugs for Lean and Optimal mixed up? :shocked:
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I would say lean,and optimal may be mixed up. Then again, have I been doing it wrong for all these years, or is the correct way to read a plug is by looking at the area of the center electrode down near the base?
Rick.
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Wait... Aren't the plugs for Lean and Optimal mixed up? :shocked:
You are correct!
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Nothing gets by us, eh?
Was that a test?
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Nothing gets by us, eh?
Was that a test?
It might have been a test.
When you're an Internet expert, you're only as good as your last post.
It's a Hell of a burden to bear.
Many don't last long........
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(https://i.ibb.co/2Nnqrw2/BD2158-EA-FDA0-410-E-9159-8-D6-BC045-D863.jpg) (https://ibb.co/2Nnqrw2)
(https://i.ibb.co/kJNqsnC/923-DFEDE-659-E-4323-8-B4-D-5-A5-CBD615383.jpg) (https://ibb.co/kJNqsnC)
korean car brand names (https://statewideinventory.org/korean-car-brands-the-list-of-korean-car-companies)
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I would have voted for 14, with 12 and 16 a tetch too hot. But I don't know nothin
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I think those images are all plugs run on leaded gasoline.
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IMO, it is always interesting to see where your brain goes first with limited information. No doubt due to the past experience of the individual.
Since I have no background information, when I hear pinging engine, my brain goes to fuel with too low an octane rating, before it goes to ignition timing that is too advanced.
Growing up in very rainy Upstate NY, engine misfiring or sputtering? My brain goes to water in the gas first. More than a couple of road trip have been saved by finding an auto parts store and dumping some dry gas into the tank.
Now that ignition systems are orders of magnitude better than they were in the 60's and 70's, it is easy to start thinking that the carb jetting needs changing when when the spark plugs looks too dark.
The following post from someone much smarter than me, a long time ago, in a galaxy far, far, away.... got me thinking about hotter than stock spark plugs. I'm glad I read it. I've been running hotter than stock plugs in a few engines ever since. I run CR7 plugs in the DR.
Today’s Dyno Project bike. Suzuki DR 650. Dead stock, 700 total miles. semi late model Suzuki DR 650 thing. Bad hesitation in lower RPMs but EGA says mixture is good, not perfect but completely safe, well on the rich side. Air cooled old farm implement engines like rich mixtures too. Guzzi Content -Ed
Engines pulls to redline well though. Clears its throat at about 5500 rpm and runs to the limiter up top.
Odd yes.
Remove spark plugs. Cross ND number with NGK number, since I actually know NGK coding very well.
10 heat range? That is a race cold plug...only really used in roadracing two strokes and some very hot high performance 4 cylinder bikes that see stupid rpm.
Installed a set of 8 range plugs, much hotter, much better for an air cooled, puss camshafted, low compression , low rpm somewhat rich running single cylinder engine...especially with dual C size 10mm spark plugs.
All better. The 10's were just staying too cold on the insulator at low rpms to self clean at all! I sent the bike back home with the guy. $5.41 cents to solve a problem plaguing the bike from new. The 10's stayed clean enough to run when they got smoking hot at higher rpms...but wide open at low rpm, not a chance. This made a 1 bhp gain everywhere ironically.
The dyno chart showed an effectively a 10 bhp gain in the zone where trouble was bad and 1 bhp up top. I was proud of this diagnosis...about 15 minutes start to finish...sweet!
The truly proper heat range for this bike and the owner's riding style is a 6...maybe a 7 if he rides more aggressively than he says he does. Says it is strictly a put around town real slow sort of bike?
Thats some interesting information. My 02 Stone that I have fought with to get it running right since the day I got it has progressed to a point that its almost right.. Still feels a little lean at just above idle, [about 30-35 in 3rd gear.] but the plugs show rich.. I used to play with plugs 100 years ago in my drag racing days, but it totally slipped my mind on this bike. Maybe Ill try jumping up a heat range or two, and seeing how it likes it.
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I think those images are all plugs run on leaded gasoline.
That would be my suspicion too. Also, some octane boosters will leave a brownish red residue on the spark plugs.
Most of the well tuned engines that I've been around that are running unleaded fuel will have white or light grey insulators. Hopefully there are no specks on them from knock. Pulling plugs and trying to make tuning decisions based on a bunch of part throttle riding will probably send the tuner on a wild goose chase.
There are sites on facebook for spark plug reading. I signed up for it thinking it was a joke but there are some good contributions there and some good examples of what a spark plug should look like if the garbage gets ignored.
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Accurate plug reading is done on new plugs... Even if running leaded race fuel there will be a whitish insulator unless the the engine is run for a hundered miles....
Plugs from my 650 Triumph land speed racer after several run wide open down the 1-1/2 mile track using VP leaded race fuel..The plug show a very slight rich mixture. The mixture color is deep down on the insulator, threaded section my need to be cut away to have a look...I use an Octoscope....
Race bike plug
(https://i.ibb.co/Wsp62dL/83905-FFF-EAAA-437-F-98-E6-36-F2505-A39-B6.jpg) (https://ibb.co/Wsp62dL)
My 61 650 A10 BSA running a mixture of non ethanol pump gas and leaded race fuel..About 25 miles of fast riding onback roads
(https://i.ibb.co/gRRV6Vn/75-A15-FCC-E705-4-AEB-82-AA-01273621314-C.jpg) (https://ibb.co/gRRV6Vn)
79 Triumph 750 , non ethanol unleaded pump gas...
(https://i.ibb.co/zVWL4vf/C73547-F4-102-C-468-E-A1-DD-861071689562.jpg) (https://ibb.co/zVWL4vf)
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Accurate plug reading is done on new plugs... Even if running leaded race fuel there will be a whitish insulator unless the the engine is run for a hundered miles....
Plugs from my 650 Triumph land speed racer after several run wide open down the 1-1/2 mile track using VP leaded race fuel..The plug show a very slight rich mixture. The mixture color is deep down on the insulator, threaded section my need to be cut away to have a look...I use an Octoscope....
Race bike plug
(https://i.ibb.co/Wsp62dL/83905-FFF-EAAA-437-F-98-E6-36-F2505-A39-B6.jpg) (https://ibb.co/Wsp62dL)
My 61 650 A10 BSA running a mixture of non ethanol pump gas and leaded race fuel..About 25 miles of fast riding onback roads
(https://i.ibb.co/gRRV6Vn/75-A15-FCC-E705-4-AEB-82-AA-01273621314-C.jpg) (https://ibb.co/gRRV6Vn)
79 Triumph 750 , non ethanol unleaded pump gas...
(https://i.ibb.co/zVWL4vf/C73547-F4-102-C-468-E-A1-DD-861071689562.jpg) (https://ibb.co/zVWL4vf)
Wish all my bikes' plugs looked like those! :thumb:
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(https://i.ibb.co/TK7Th1m/C73547-F4-102-C-468-E-A1-DD-861071689562.jpg) (https://ibb.co/TK7Th1m)
Liked this image best.
One article I read discussed selecting proper heat range. They mentioned that a heat discoloration of the shell first two or three threads from the end and plating being cooked off the shell electrode out to the 90 degree bend indicated that you were running the plug at the proper heat.
The plug in the picture indicates both these conditions excellently.
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(https://i.ibb.co/2Nnqrw2/BD2158-EA-FDA0-410-E-9159-8-D6-BC045-D863.jpg) (https://ibb.co/2Nnqrw2)
(https://i.ibb.co/kJNqsnC/923-DFEDE-659-E-4323-8-B4-D-5-A5-CBD615383.jpg) (https://ibb.co/kJNqsnC)
korean car brand names (https://statewideinventory.org/korean-car-brands-the-list-of-korean-car-companies)
a picture is worth 1,000 words!
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Thats some interesting information. My 02 Stone that I have fought with to get it running right since the day I got it has progressed to a point that its almost right.. Still feels a little lean at just above idle, [about 30-35 in 3rd gear.] but the plugs show rich.. I used to play with plugs 100 years ago in my drag racing days, but it totally slipped my mind on this bike. Maybe Ill try jumping up a heat range or two, and seeing how it likes it.
Yeah, until I read it, I would have chased the idea of a better running bike with adjusting only the jetting. Kudos to the Guru who did the diagnosis. The Air-Fuel meter is a tool that is much easier to read.
"Low compression, puss camshafted......... Air cooled old farm implement engines like rich mixtures too." This guy has been around the block a few times! :wink:
The experts agree with Road Rocket. Plug reading should only be done on new plugs.
I've read more than a few articles on the correct technique/throttle chop/etc. to perform an accurate plug reading.
I'm sure Erv Kanemoto or Kev Carruthers can read a new plug well, but anytime I've tried to read a new plug, they have always looked great if the bike ran at all.
So I have little confidence in reading a new plug to tell me anything about jetting, timing, plug heat range, etc.
Oddly enough, even it is advised to read only new plugs, none of the spark plugs shown in the images of the spark plug reading tutorials I've seen look like they have less than several hundred miles on them.
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I'm in the process of replacing my plugs . The originals have 24,653 miles on them and are still working just fine ... but ... I had them out checking the valves so I'm getting new ones now. I came across this chart in my quest for maybe getting a different heat range to help with better mpg. But I'm staying with the same heat range but going to Iridium if I can find some. Here's the chart.
My question was : does the heat go up or down with the numbers ?
(https://i.ibb.co/s341Mn1/NGK-Spark-Plugs.jpg) (https://ibb.co/s341Mn1)
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Cool chart…lower the number hotter the plug
(https://i.ibb.co/B3k5xxy/67-FB1-E30-9523-46-CB-9348-9996-A0790477.jpg) (https://ibb.co/B3k5xxy)
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Yes, completely opposite from Champion.
kk