Sparkplug problems

That is the plug I use on my 74 850. Running Electronic Ignition and non-resistor plug caps.
 
Mine nye NGK BPR7ES tændrør bliver sodet til
This translate as sooty plugs.

You have given insufficient information.

What sort of ignition system? If electronic does it require either resister plugs or resister cap? But not both. Are you running wire filled and not carbon filled plug lead?

BP7ES or BPR7ES are both suitable plugs depending on the answers to the questions.

But actually sooty plugs probably means carburetor settings are wrong or the carb is worn out.

Or oil is entering the combustion chamber. Does the bike smoke and are the valve seals in good condition?
 
The first thing I would do to address sooty plugs is replace the needle jets in the carbs. The action of the needle wears on the jet. Use the same .106 size. No need to remove the carbs. Remove the float bowls and replace the needle jet. The main jet should be okay to reuse. The NGK 7 sparkplug is the correct heat range for a Commando, in fact some of us use the cooler NGK 8 with success.
 
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The first thing I would do to address sooty plugs is replace the needle jets in the carbs. The action of the needle wears on the jet. Use the same .106 size. No need to remove the carbs. Remove the float bowls and replace the needle jet. The main jet should be okay to reuse. The NGK 7 sparkplug is the correct heat range for a Commando, in fact some of us use the cooler NGK 8 with success.
I agree needle jets. And sometimes needles as well
 
The first thing I would do to address sooty plugs is replace the needle jets in the carbs. The action of the needle wears on the jet. Use the same .106 size. No need to remove the carbs. Remove the float bowls and replace the needle jet. The main jet should be okay to reuse. The NGK 7 sparkplug is the correct heat range for a Commando, in fact some of us use the cooler NGK 8 with success.
You developed that response to the 2 original posts!?!
Wow...most impressive.
 
You developed that response to the 2 original posts!?!
Wow...most impressive.
He said new plugs are getting covered in soot.

If the plugs are compatible with the ignition system. Which I asked but did not get a reply yet.

Then next best guess would be mixture or oil leaking.

If mixture then worn needle jets are a very likely cause.

As per John Healy's articles.
 
Give the man a chance. Maybe he decided to acquire a Commando just recently.

Jesper: Please translate your statements using Google Translate or similar services.

- Knut
The comment was because a similar post a few weeks ago did turn out to be an issue.
 
You developed that response to the 2 original posts!?!
Wow...most impressive.
He said new plugs are getting covered in soot.

If the plugs are compatible with the ignition system. Which I asked but did not get a reply yet.

Then next best guess would be mixture or oil leaking.

If mixture then worn needle jets are a very likely cause.

As per John Healy's articles.

He said new plugs are getting covered in soot.

If the plugs are compatible with the ignition system. Which I asked but did not get a reply yet.

Then next best guess would be mixture or oil leaking.

If mixture then worn needle jets are a very likely cause.

As per John Healy's articles.
My comment was one of question/caution considering the never before seen poster.

You offer a lot of ifs, best guess and maybes in your response toward my comment, pointed at a questionable poster not heard from in two days since original posting "spark plugs"
Thus my response.
Lots of scamming around, jesper can verify if they are viable.
As per my own observations.
 
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My comment was one of question/caution considering the never before seen poster.

You offer a lot of ifs, best guess and maybes in your response toward my comment, pointed at a questionable poster not heard from in two days since original posting "spark plugs"
Thus my response.
Lots of scamming around, jesper can verify if they are viable.
As per my own observations.
"You offer a lot of ifs, best guess and maybes in your response toward my comment "

Bit disapointing you feel that.

I tried to offer an investigation path. A decision tree of "if this then that. " - which is the normal way of tracing down a fault.

A logical approach of elimination is better in my experience than randomly throwing options at a problem.

While also recognising it was an unusual first post. Language issues perhaps.

But each to his own. if you don't like my posts then please feel very free to block me. Your definitely most welcome to do so. Have a nice day. 🌻🌻🌻
 
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Don't be too disappointed. Just offering an honest and factual observation.
Still no follow up from original poster.
Please know blocking applies both ways although I don't use the feature as I want to hear all opinions rather than assuming I will not agree with another.
You too be well.🙏
 
Don't be too disappointed. Just offering an honest and factual observation.
Still no follow up from original poster.
Please know blocking applies both ways although I don't use the feature as I want to hear all opinions rather than assuming I will not agree with another.
You too be well.🙏
All good. 👍

Let's see if the OP comes back with any useful information.
 


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