Plugs carbonned up

[ccs]

Hi Guys;

I recently bought an 82 GS850G. The bike runs very well, but I recently pulled the plugs and saw that they were carbonned (sp?) up somewhat.

I cleaned them with a brass wire brush and am wondering whether I can use a hotter/cooler running plug or need to make some changes to the carbs (I bought the bike used about 2 months ago and have put 1500 miles on it since).

TIA.

Charles...

[GSstiny]

Black gunk=running rich. Does the intake or exhaust have any mods? Pods, 4-1, etc? It may just need adjusting, possibly rejetting if any mods have been done. If you have a manual check and see if the plugs are stock.

[chef1366]

Is it oil or gas on the plugs?

[ccs]

The plugs just have a black, sooty deposit -- no oil -- cleans up real nice with a wire brush. I also checked the gaps and they're OK.

There are no intake/exhaust mods that I am aware of -- everything looks stock.

Charles...

[flyingace]

If all of the plugs are black/sooty and you are running stock airbox and exhaust, I have to wonder about the condition of your air filter. Have you cleaned it lately? Another possibility is weak spark - maybe the caps/wires need replacing.

If only 1 or 2 plugs are black, then you may have to look at those carbs needle/seats getting stuck open. Also, check if #1 & #4 or #2 & #3 are the black plugs. Maybe a weak coil.

[bwringer]

A few thoughts:

How much are you using the choke? You shouldn't need to use the choke for more than 30 - 60 seconds. Some people have the habit of starting a bike on full choke and leaving it there for several minutes while they hunt for their gloves, say goodbye, drink a cup of coffee, etc.

Also, I've found that it's durn near impossible to clean plugs completely. They always seem to re-foul much more quickly (I'm speaking from experience in boat and lawnmower engines.) You might try starting over with a fresh set of NGK B8-ES (the stock and absolutely most perfect plug on the planet for your GS). You can get them at Advance Auto and Pep Boys for less than $2 each -- ask for stocking number 4011, since B8-ES is not in the computers. Don't let them talk you into wasting money on Platinum Iridium Super Funky Multi Electrode plugs.

If the fouling continues, then you need to address the mixture problem. Different spark plugs are not a substitute for making whatever adjustments or repairs are needed in your carbs and intake system.

"Colder" or "hotter" plug designations have nothing to do with how easily the plug fouls.

As others have said, you may want to check your air filter for clogging. The foam element will need to be washed thoroughly (warm water and dish soap is sufficient) and then VERY LIGHTLY re-oiled and installed. It's pretty easy to get too much oil on the element, so if you've recently re-oiled the filter element that could also be creating the problem. Use paper towels and squeeze every bit of loose oil out of the element so it's just barely oiled -- the foam should not even feel oily to the touch.

[Jethro]

Wow, the 850's use a different plug than the 1100's. I run the stock NGK D8EA's. Learn something new every day- guess I can go to bed now!

As the uncomperable Mr. Wringer stated, colder or hotter plugs will not help plug fouling. I learned this last year. Our bikes should never need a different temp plug, unless it's got engine modifications.

There can be a lot of reasons for carbon fouling, but these bikes with thier "oh-so vaccum dependant CV carbs" means that 9 times out of 10 it's a fuel mix problem due to soemthing being worn out or clogged. You may need to do a carb clean, paying special attention to the mixture screw ports and pilot air jet ports- but check all the simple things first.

Also don't rule out a weak spark or poor timing. Old, cracked plug wires and caps can make for some sooty plugs.

[arveejay]

If you have OEM filter it shouldn't need oiled. Set you air screws at 1 1/4 turns out and try that.