Spark plug read

[Beardoh]

I recently cleaned the carb on my '83 ATC185s, the only change I made after cleaning is I turned the fuel screw 2 turns out (witch is stock, It was at 1 1/4 when i bought the bike) I have road it for about 1 hour since at various RPM's and just pulled the plug out and was confused with how it looked, the outside was covered in carbon but the tip is pure white. Let me know what you all think. Thanks

[team-red-rider]

LEAN! richen it up

[Bryan Raffa]

yes!! hot hot hot too lean.

[TimSr]

By "fuel screw" Im guessing you mean idle air screw, which is adjusted for best throttle response off of idle, and has no bearing on your plug readings, as it only affects air/fuel at idle and this circuit is bypassed as soon as you begin to open the throttle.

There is a good stickied thread on taking plug readings and adjusting jetting and needle setting.

[team-red-rider]

fit it soon DO NOT RUN IT! it WILL COOK your engine~

[bigreddaddy]

By "fuel screw" Im guessing you mean idle air screw


I would think he is talking about the Pilot screw.

[Beardoh]

I would think he is talking about the Pilot screw.

Its the one at the front of the float bowl (closest to the cylinder).
I have tried raising the needle one position (in the 3rd from the top instead of the 2nd) and the new plug i put in still looks the same. The exhaust I have is really rusted, it's missing the end (with the spark arrester), maybe it's part of why it is running lean? Could putting on a new exhaust help?

[TimSr]

Pilot screw aka pilot air screw, aka idle air screw - The one that does not move the thottle slide up.

Open exhaust will cause a lean condition. I would not monkey with jetting until you have the exhaust installed that you plan on running in it. Tuning the carb to your existsing exhaust is pointless unless thats how you plan on running it.

[traxxasx]

Yea your lean put it back to how it was. Or richen up the jets.

[Beardoh]

Yea your lean put it back to how it was. Or richen up the jets.

I went to the bike shop today and got a few bigger size mains, so I'm gonna try and get it tuned over the next couple of days. Should I raise the needle back to the stock setting and just start with the bigger main? or leave the needle as it is and just switch the main? Jetting seems harder to tune on these four strokes than the twos (what i'm used too)

[bigreddaddy]

If it were me, I would definitely put a complete exhaust on it.

[Beardoh]

If it were me, I would definitely put a complete exhaust on it.

Any other aftermarket pipes I can get for it besides the Cobras?