Black-dry plugs

[gekkechef]

Hello again,
I check my spare plugs yesterday, and they were black and dry, all 4 of them, #1 was less, lets say 1/2 way to normal (looking at the pictures on the haynes manual)
I read last night a lot about the topic in the forum, but before I start turning screws in the carbs, I would like to hear your suggestions, perhaps the ignition ??
Any ideas about how can I troubleshoot this??
My GS 1000 L does about 12 to 13 km with a liter and I use 98 octanes, I think she is very thirsty (like me...... ) I just use 5 octanes lager :-D
Thanks in advance guys

[Sprockets]

Same Problem here

Hello again,
I check my spare plugs yesterday, and they were black and dry, all 4 of them, #1 was less, lets say 1/2 way to normal (looking at the pictures on the haynes manual)
I read last night a lot about the topic in the forum, but before I start turning screws in the carbs, I would like to hear your suggestions, perhaps the ignition ??
Any ideas about how can I troubleshoot this??
My GS 1000 L does about 12 to 13 km with a liter and I use 98 octanes, I think she is very thirsty (like me...... ) I just use 5 octanes lager :-D
Thanks in advance guys

Hi gekkechef, I have the same problem with my bike, may be worst (the sparks plugs are black, and after some milles, some of them stop working.
I could solve it for a while, turning the front screws of the carbs that let you the black spark plugs clock counter wise. Also check with the specs of the bike if you are using the correct spark plugs (in 550 are NGK B8ES) and check if it performs better taking out the FM filters that are inside the spark plug connector (those are kinda fusibles, little tube-shaped stuff, you have to elongate the springs after removing them).
Also, check the air filter (change the foam if it is dirty).
Greetings
Emanuel

[gekkechef]

black dry plugs

Thanks emanuel for the sugestions.
I notice after cleaning the plugs yesterday, the cold start was this morning at 2c outside temperature instant.
Then I think the mix is too rich.
I am also from Baires, leaving in Holland for 18 years now.
Nice to see guys down there still loving the old stuff I use to wonder as a teenager.
greetzz

[flyingace]

Accoring to my math, you are getting 34-36 MPG. This is not too bad, depending on how hard you drive your bike. I get 38-40 on my unmodified 850.

The question is, which circuit(s) in your carbs are causing the black sooty plugs? Many forum members recommend 'plug chops', that is, running the bike at speed, then stopping and quickly shutting off the engine to look at the plugs. The idea is to let the bike idle as little as possible. Run the bike at 60-70 MPH for 5 minutes and look at the plugs. If they look tan and clean, your problem is in the idle or off-idle circuits. If they still look black/sooty, the issue is in the main circuits.

If you can determine which circuit is causing this, it will help other forum members fix the condition.

[gekkechef]

Accoring to my math, you are getting 34-36 MPG. This is not too bad, depending on how hard you drive your bike. I get 38-40 on my unmodified 850.

The question is, which circuit(s) in your carbs are causing the black sooty plugs? Many forum members recommend 'plug chops', that is, running the bike at speed, then stopping and quickly shutting off the engine to look at the plugs. The idea is to let the bike idle as little as possible. Run the bike at 60-70 MPH for 5 minutes and look at the plugs. If they look tan and clean, your problem is in the idle or off-idle circuits. If they still look black/sooty, the issue is in the main circuits.

If you can determine which circuit is causing this, it will help other forum members fix the condition.

Thanks for your clear troubleshooting advice.
I did not think about doing that.
Clever man.
I will certainly do so and tomorrow hope to post how it went

[flyingace]

I wish I could take credit - I'm just passing on what I've read here. It's amazing what you can learn reading these posts.