Topic: spark plug stays white lean or rich

[nuke]

So i've been fidlin' with my 78 750 f2 carbs to get the right mixture. All pre-work has been done, carbs super clean running stock 4-1, stock filter and d8es plugs. The bike was running pretty good but when I took the pugs out just to check they were pretty white, they looked like # 23 on the link I've posted, but the tip (metal part is even whiter) So I udjusted my mixture to make it a little richer, still ran pretty good but exhaust stunk of gas and more smoke out of the pipe. Took the plugs out again expecting them to be darker, no such thing. I've been to both ends of the mixture and plugs stay white and clean. If bike runs good should I worry? How long should the engine take to cool down after a good run in reg (25 C) temp. I thought it was little long when I touched the motor an hour later and it was still kinda warm. That running lean hole in the piston scenario scares the caca out of me.

 http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html

 any input appreciated
thanks
nuke
     

[HondaMan]

What kind of gas are you using? Some posts have appeared here lately about the "Tecra" additive in the gas, causing chalk-white plugs. Switching gas makes the plugs color up again. Apparently, some gas company is adding something to his gas that causes this symptom, but the bike runs fine.     Could this be your situation?

[nuke]

Well I never heard of Tecra but I've been filling with the cheapest thing going when I fill up. I'm in Toronto area and use Sunoco. I'll try filling somwhere else for the next few fills. See what happens

Thanks for the heads up

nuke
BTW how long should it take for the plug to get light brown? first run or a few long rides?

[eldar]

Well lets see. You have an F2 which was made by honda to run lean. Now you did not say what plugs you are using but you should not smell much, if any, gas from your exhaust. It means that you are now passing poorly burnt fuel. It does take a while for these engines to cool down, still kinda warm after an hour I would say is ok. How warm is kinda? Could you still your hand on the engine and leave it there? Could you pul out the plugs without getting burnt? If so, then I think you are ok.
You should readjust your idle mix back to where it was, IMO.

[hcritz]

My 77's plugs run very clean...the insulators are mostly white...the outside metal edges are dark...Bike runs beautifully. So I'm not fiddling with it! It's not even very cold natured in the mornings...I can fire it up and ride with no hiccups...if it's cold out...half choke for about 1/2 mile and all is good.
Most of the automotive plugs I see these days look very similar...I think the newer fuels just run very cleanly and if you aren't burning any oil...especially from valve guide seals...the plugs should look pretty white. I think this is more true for the 77-78s with accelerator pumps...

[dusterdude]

Well lets see. You have an F2 which was made by honda to run lean. Now you did not say what plugs you are using but you should not smell much, if any, gas from your exhaust. It means that you are now passing poorly burnt fuel. It does take a while for these engines to cool down, still kinda warm after an hour I would say is ok. How warm is kinda? Could you still your hand on the engine and leave it there? Could you pul out the plugs without getting burnt? If so, then I think you are ok.
You should readjust your idle mix back to where it was, IMO.

eldar,he said d8es.

[nickjtc]

Well I never heard of Tecra but I've been filling with the cheapest thing going when I fill up. I'm in Toronto area and use Sunoco. I'll try filling somwhere else for the next few fills. See what happens

I wonder if this is a Canadian gas thing. My 650 runs really well and doesn't seem to get too hot, even in high 30s weather, but the plugs look like it is running lean.

[nuke]

  Good to hear all of this. After an hour It is just slightly warm, I can hold my hand on the motor with no pain. The mixtue now is not giving me a gas smell out of the exhaust. This only happened when at the richer setting I was trying. A far as the plugs go all is white with the bottom of the threads showing black/dark brown.(and they are NGK platinum just changed from the cheaper Champions) I now have it at the 1-3/4 setting that the F2 is suppose to be, and running fine. Thank you for all the input. I can now ride without constantly having this on my mind.

 
nuke