Carb Jetting 101: Terms, Tips and Jetting Theory

[Dammit!]

Just let off the gas and kill the motor. Automatics will coast in gear.

[stoney420]

oh ok thanx, i figured it would lock up when u hit the kill switch cause u cant push it when its in gear..

[Dammit!]

I'm not an auto expert but the couple I've had would roll in gear. Try it going slow first I guess.

[rally4x4racer]

i chop the autos in nuetral - seems to work fine.

also - I wanted to add some more info on the plug reading. http://www.4secondsflat.com/Spark_plug_reading.html it is not for dirt, but helpful no doubt

frankencelery - did you get that fixed? sounds like a needle diameter prob. look at the keihin page posted earlier

good work, dammit!

[Frankencelery]

No, I never did. My 200s hasn't been run for awhile, and I've been trying to replace a tire that doesn't hold air, so I haven't gotten back to it. I think I'll try putting that 38 pilot jet back in when I get around to it.

[The Goat]

1985 200x bored two sizes over, no air box lid, cobra exhaust. i'm prolly 100 feet below sea level or so, what should my carb settings be?

i know all trikes are different, but if i could get just a general idea.

main jet, pilot jet, air/fuel and needle position?

[big schott]

I am working on a 1984 Big Red for a friend. The carb needed cleaning and I went through everything like I have 10 or 15 times before (on other machines).
The 200 starts everytime on the first pull and does not need the choke (odd for Minnesota in Oct). I took it for a ride this afternoon and found it to sputter at 1/4 and 1/2 throttle and it did not seem to run good at top end (Air Fuel needle at 1 1/2). I set the air/fuel at 3/4 and it ran better. But when I turned the needel in all the way it runs good. I know that you should not run anything with the needle in all the way so that is why I have the Q?.

What do I need to do?

[big schott]

I never thought about the air filter. I'll put on a new one, and I was thinking about the resetting of the needel.
I'll do this this week and let you know what I find.

THANKS!!

[harley9399@veri]

need a carb for a ATC Big Red 1984 model 200es this machine set for 10years keeps filing plugs?\Thanks Mitch

[Danold]

so I just got my 85 x done and im stoaked. The only problem i am having is it not running past 1/4 throttle and just bogs and sputters. It also will not idle.

However, when I put the chocke on it revs all the way out and revs quik and idles high.

I havent really messed with it because of not knowing where to start. But mabye one of you guys could help me out?

[NOS_350X]

That would meen your running to lean. (choke richens it up) Pick up a larger main jet and move your needle clip down (raising the needle)

[Danold]

ok ill give it a try. I was thinking it was runnig rich becuase when it was missing it was plowing greenish black smoke. It just looked greenish mabye color blind or somthing. Thanx for the help.

[3WW Star-CoeShow]

Usually if the engine seems to run better WITH the choke, it indicates that the pilot jet is plugged up or way too small, not the main jet. This does not mean that you may also have issues with the proper main jet size.

Avoid making numerous changes at once. Change one component at a time. This will aid in figuring out which circuit is causing the problem/s.

Good luck and ride safely

[Danold]

got it fixed. The choke was messed up and wouldnt stay open. Also the main was bent from over tightening.

[BELGIUM KXT250]

"When adjusting the air screw, tightening the screw is richer and loosening it is leaner. This is because tightening the screw allows less air to pass (resulting in more fuel in the mixture which = richer), loosening it lets more air through."

I don't really understand that because I checked at my carb and by tightening the air screw it raises up the throttle valve so I was thinking that it allows to let more air to pass and so it's leaner... could you explain where I am wrong ?