Does anyone know what direction, tightening or loosening the air/fuel mixture screw corresponds to richening or leaning it out?
When you screw it in until snig and then start backing it out, the farther you back it out the richer it will be :thumbs:
Hey guys, I just ran my rig on a new plug for the first time for about 10 minutes. I pulled the plug and its hasnt darkened much at all, so this means running lean right?
So I already have the air/fuel mixture screw out 3 turns, should I go half turns out until I get the perfect chocolate color?
Alright guys since I got impatient waiting for an answer this is what I did.
I changed the mixture screw and ran it for at least 10 minutes each ride on settings of 2 1/2, 3 and 4, with no color left on my plug. I also set the mixture screw at 2 and the machine wouldnt even start.
So I am at a complete lose right now. Whats the deal?
Could this mean I am not jetted large enough?
What are your jet settings again?
~Brian
155 Main
25 Pilot
You're at 2 turns and it won't start?
~Brian
Yeah at 2 turns out it wouldnt start, so I set it at 2 1/2 and it would run fine. I have also run it at 3 and 4 turns out, ran fine there as well.
Quote from: BoisBlancBoy on May 30, 2008, 03:06:49 PM
Yeah at 2 turns out it wouldnt start, so I set it at 2 1/2 and it would run fine. I have also run it at 3 and 4 turns out, ran fine there as well.
At 2.5 turns you don't have any hesitation through the gears?
~Brian
If there was, it wasnt much. Whats your thinking if I do have some hesitation at 2.5? I have only riden it just a couple miles at 2.5.
If you're okay at 2.5 turns and you have no hesitation in the throttle going through all the gears then you are in good shape.
Do you know how to read your plug?
~Brian
Yeah but so far the half hour total on my plug hasnt shown anything. how long of a ride do I need before I will know one way or the other?
Quote from: BoisBlancBoy on May 30, 2008, 03:56:22 PM
Yeah but so far the half hour total on my plug hasnt shown anything. how long of a ride do I need before I will know one way or the other?
I was told to install the new plug, go through the gears at high speeds, and kill the engine. Pull them plug and read.
If it's super black, or it's a nice light brown around the porcelain at the electrode you're in good shape.
~Brian
Well so far, the plug and porcelain looks brand new!!! Thats why I am so stumped.
Air/fuel screw wont do much through the rpm range. If there is still no color on the plug. Jet to 160 and retry the plug reading. WFO in like third, cut engine, stop pull plug and check.
Lets say I did re jet to a bigger main, what would happen if I went too big?
plug will be black or very dark brown indicating too much fuel.
Should I just order a few sizes above the 155 that I currently have?
What about my other carb settings? Pilot jet?
For your modifications, anything bigger than a 155 is just too big. Have you been riding the bike or just letting it idle before checking the plug? It should have some type of deposit on it riding it like you stole it before you pull the plug. Post a picture of your plug. If you have a camera with a digital macro setting, select "macro" and this will enable you to get close up to the electrode area. Post it up your picture, or sen it to me at imabeachbum2001@yahoo.com.
~Brian
Nope no idling, except for when I first get her started. Then take her out for a ride at half throttle most of the time and then the occasional wide open.
I will try and get some pictures, not sure if my camera will take a close up picture or not.
Quote from: BoisBlancBoy on May 31, 2008, 10:20:45 AM
Nope no idling, except for when I first get her started. Then take her out for a ride at half throttle most of the time and then the occasional wide open.
I will try and get some pictures, not sure if my camera will take a close up picture or not.
Have you adjusted your idle screw?
~Brian
Ok, well this is the best picture I could get! I know its not very clear but you should be able to see how white the plug is.
[attachment deleted by admin]
Quote from: Flynbyu on May 31, 2008, 10:37:50 AM
Quote from: BoisBlancBoy on May 31, 2008, 10:20:45 AM
Nope no idling, except for when I first get her started. Then take her out for a ride at half throttle most of the time and then the occasional wide open.
I will try and get some pictures, not sure if my camera will take a close up picture or not.
Have you adjusted your idle screw?
~Brian
Yeah I have adjusted it so that she runs smooth at start-up just sitting there. If I went any slower she would run choppy, or eventually die.
Just checking. If you are idling, and not having any blog going through the gears, you are in good shape!
:thumbs:
The plug is hard to see, but you your benefit, look between the porcelain and the electrode, and the precelain and the inside of the threaded area on your plug.
As long as there is no powdery white substance on the plug, you're in good shape.
~Brian
There does seem to be a little white powdery substance on the back side of the electrode, but very very little.
Is there anything I can do to richen it up some? I just dont want to be on that fine edge of buring a hole in the piston!
Quote from: BoisBlancBoy on May 31, 2008, 11:15:48 AM
There does seem to be a little white powdery substance on the back side of the electrode, but very very little.
Is there anything I can do to richen it up some? I just dont want to be on that fine edge of buring a hole in the piston!
Richen the mixture by using the air/fuel mixture. You're at how many turns now?
~Brian
I am at 2.5 now.
I did take a ride on it for 10-15 minutes at 4 turns out with that same plug I showed in the picture.
What is the worst thing that could happen if I go too rich?
Waste precious gasoline.
:lol:
~Brian
Yeah at this day in age thats no joke!!