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79fordblake
02-21-2011, 08:07 PM
Prolly a dumb question but do you turn the pilot screw in or out to make it leaner? I am just now getting close to getting the carb on my 185s right.
With the aftermarket filter and exhaust I finally got it to run right on the top end with a 102.5 main jet.

I had the needle set at the 2nd notch from top and from idle to stabbing it to about half throttle it wanted to cut out. So I lowered it to the 3rd notch from top and now it revs up fine but it is just a little bit rich. Can I get this fine tuned more with the Pilot screw adjustment? Thanks guys, this is the closest it has been to being right since I got it almost two years ago.

MonroeMike
02-21-2011, 08:11 PM
185s, clockwise=leaner.

Headsup
02-21-2011, 08:17 PM
in less air gets threw, out more air gets threw

briano
02-21-2011, 08:19 PM
Hey Headsup some carbs are the opposite.

camoweasel
02-21-2011, 08:50 PM
in less air gets threw, out more air gets threw

NO! 185s have a fuel screw. Your thinking of an air screw.

But correct answer as repeated from above is clockwise to lean it and counter-clockwise to richen.
When jetting, its better to start with the fuel screw then work your way to the needle, then to the main jet. So in other words, try messing with the fuel screw and the needle first, to solve your problem, then go back and recheck the main.

79fordblake
02-21-2011, 10:17 PM
I had the stock 95 main jet in it at first. After I put the aftermarket items on it it went extremely lean. I have messed with the pilot jet and needle many times in the past never got the carb right. Then I stepped up to a 100 main jet and then 102.5. Now the carb is so dang close to being right. It over fuels just a little bit until I get to wot. With a carb this old I may be as close to perfect as Im gonna get. But it would be nice for it to be a little leaner at mid throttle. Needle set a 2nd notch is a little to lean, needle set at 3rd notch is a little to rich. Hopefully after I mess with the Pilot screw some more I will find a happy medium.

1984 honda 200s
02-21-2011, 11:07 PM
what does that 102.5 main jet do over the stock 95? id like to know this since i got a 200s lol

Dirtcrasher
02-21-2011, 11:22 PM
Hey Headsup some carbs are the opposite.

That would be a fuel screw, not an air screw..............

79fordblake
02-21-2011, 11:22 PM
what does that 102.5 main jet do over the stock 95? id like to know this since i got a 200s lol

Well without goin into much detail I have aftermarket air filter and exhaust. So I have more air flow coming in and out of the engine than with stock air filter and exhaust. With more air flow you gotta have more fuel to go with it. Bigger jet allows more fuel.

Headsup
02-22-2011, 09:50 AM
The 185s has a Fuel/Air Mixture screw, So idk what the hell u guys r saying to me.. You turn the screw in for less air more fuel, Out for more air less fuel.

MonroeMike
02-22-2011, 01:18 PM
From the manual.

jensenracing77
02-22-2011, 06:34 PM
almost always... if the mixture screw in on the air filter side of the slide it is an air screw and if it is on the engine side it is a fuel screw. when it is a fuel screw it has a near set amount of air that will pass, you give it more or less fuel for that set amount of air. when it is an air screw, you have an amount of fuel that is a somewhat set amount from the pilot jet and you give it more or less air to mix with the fuel. the needle should have little to no affect on idle mixture if all else is adjusted right. also the slow idle circuit has no affect after about 1/8 throttle and that is when the needle adjustment kicks in. at WOT is where the main jet is adjusted.

jensenracing77
02-22-2011, 06:40 PM
also.. always remember on this engine family you MUST have good springs on the advancer or you will NEVER get a good idle. you can't get just the springs, you have to get the entire advancer.

for people that don't know... the advancer is for the timing advance and is located under the cover at the top left side of the head. it mounts on the cam.

79fordblake
02-22-2011, 08:03 PM
Today after I warmed the engine up good I turned the pilot screw clockwise 1 turn. For now it seems like it fixed the problem. Ill find out for sure on the trail this weekend.