popping from exhaust front cylinder

[kidastra]

ok then, I won't touch anything. Where is this fuel screw exactly, maybe I turned it by accident?

Do you guys recommend a sync?

[kidastra]

LEANER

RICHER

so this picture is wrong?

[Blaine]

LEANER

RICHER

so this picture is wrong?

No.......Picture is correct Turn left (Rich) ...........Turn right (Lean)

[MadCow]

LEANER

RICHER

so this picture is wrong?

No.......Picture is correct Turn left (Rich) ...........Turn right (Lean)

No, that picture is ass backwards. It should read "If it is Rich, turn it left (counter clockwise)...if it is lean, turn it right (clockwise)"

" When your bike is acting lean, turn the airscrew in (clockwise). When it feels a bit too rich, open the screw (counter clockwise) to allow more air into the mixture."

[kidastra]

LEANER

RICHER

so this picture is wrong?

No.......Picture is correct Turn left (Rich) ...........Turn right (Lean)

No, that picture is ass backwards. It should read "If it is Rich, turn it left (counter clockwise)...if it is lean, turn it right (clockwise)"

" When your bike is acting lean, turn the airscrew in (clockwise). When it feels a bit too rich, open the screw (counter clockwise) to allow more air into the mixture."

I think that's where most of my confusion comes from, let me sum it up
I had popping, which is coming from a lean condition, so I need to reduce the air coming into the carb to compensate for this lean fuel condition. Turning the screw RIGHT lowers the air, which in turn balances the fuel/air ratio, making the mixture richer.

Still makes 0 sense to me though, assuming the screw is a fine point at the end, screwing it in would in face restrict the amount of fuel going in, and screwing it out would enlarge the hole, allowing more gas to go in. The air is NOT passing through a little needle, the only thing this screw adjusts is the amount of gas coming in compared to the amount of air coming in. I still think the picture is correct in the descriptions and that right is leaning the fuel, left is richening the fuel.

I know it sounds like I am looking for problems where they aren't, to be fair I am trying to understand everything, this goes against everything I've previously learnt about carbs.

[MadCow]

I think that's where most of my confusion comes from, let me sum it up
I had popping, which is coming from a lean condition, so I need to reduce the air coming into the carb to compensate for this lean fuel condition. Turning the screw RIGHT lowers the air, which in turn balances the fuel/air ratio, making the mixture richer.

Still makes 0 sense to me though, assuming the screw is a fine point at the end, screwing it in would in face restrict the amount of fuel going in, and screwing it out would enlarge the hole, allowing more gas to go in. The air is NOT passing through a little needle, the only thing this screw adjusts is the amount of gas coming in compared to the amount of air coming in. I still think the picture is correct in the descriptions and that right is leaning the fuel, left is richening the fuel.

I know it sounds like I am looking for problems where they aren't, to be fair I am trying to understand everything, this goes against everything I've previously learnt about carbs.

I think your confusion is because it's not a fuel screw, it's an air screw. That screw only adjusts the amount of air up or down, which makes the picture ass backwards.

[MadCow]

No, that picture is ass backwards. It should read "If it is Rich, turn it left (counter clockwise)...if it is lean, turn it right (clockwise)"

" When your bike is acting lean, turn the airscrew in (clockwise). When it feels a bit too rich, open the screw (counter clockwise) to allow more air into the mixture."

WRONG! Turning the screw on the carb to the LEFT will allow MORE gas. Turning the screw to the RIGHT will close the screw, limiting the gas.

Lefty loosey, righty tighty.

Now I see why there is so much damn confusion over this topic.

Since when is that screw a fuel screw? It ain't. which is why when he turned it to the right, restricting air, he enriched the mixture.

[MadCow]

No, that picture is ass backwards. It should read "If it is Rich, turn it left (counter clockwise)...if it is lean, turn it right (clockwise)"

" When your bike is acting lean, turn the airscrew in (clockwise). When it feels a bit too rich, open the screw (counter clockwise) to allow more air into the mixture."

WRONG! Turning the screw on the carb to the LEFT will allow MORE gas. Turning the screw to the RIGHT will close the screw, limiting the gas.

Lefty loosey, righty tighty.

Now I see why there is so much damn confusion over this topic.

Since when is that screw a fuel screw? It ain't. which is why when he turned it to the right, restricting air, he enriched the mixture.

It matter not if that screw is allowing for more gas or restricting for less air. The end result is the same for this bike. The confusion is unnecessary. In his video, he turned the screw and the popping stopped. Since that was his problem from the jump, the problem is solved. If he is anywhere from 1 turn to 2.5 turns out from dead stop, he is fine.

Chill out. damn, he's trying to understand that air screw. I'm explaining what is happening with that screw. That picture is ass backwards. That screw only changes the air, and does not touch the fuel. You turn it to the RIGHT ; CLOCKWISE to enrich the mixture, making that picture dead wrong.

It DOES matter that he understands what is happening when he turns that airscrew.

[MadCow]

Still makes 0 sense to me though, assuming the screw is a fine point at the end, screwing it in would in face restrict the amount of fuel going in, and screwing it out would enlarge the hole, allowing more gas to go in. The air is NOT passing through a little needle, the only thing this screw adjusts is the amount of gas coming in compared to the amount of air coming in. I still think the picture is correct in the descriptions and that right is leaning the fuel, left is richening the fuel.

THIS IS CORRECT! Forget all about the lean condition blah, blah, blah. Turn that screw in either direction until your popping stops and you have the best idle possible and leave things alone.

I really ought to lock this thread right now because it seems you finally understand it. But, I won't just in case some more insanity needs a place to happen! [emoji2]

Gawt damnit Keith. Turning that screw in DOES NOT restrict fuel. It restricts AIR.

[MadCow]

Airscrew, Fuel screws, lol


Ya'll killing me today....

[MadCow]

I'm no carb expert at all...

Still love ya brother!!

[MadCow]

Y'all can get wrapped up in whether or not the screw on the Mikuni carb used on the 1400 is metering air or fuel all you want. His problem has been solved by what has been done already. I'll pass on Carb Adjustment 101 and go for a ride today on my fuel injected bike.

In the meantime, maybe this video will help you guys in your venture to become carb experts!



[youtube][/youtube]

I'll have to hit this when I get home...don't have speakers at work.

[kidastra]

I've been watching that video, I almost posted it.

starting at 1:00 he "splits" the carb in 2. Air side, engine side.
the 1400 a/f screw seems to be engine side, metering fuel. So to stop my popping I restricted fuel. Leaning it.

so is it safe to assume my popping was from being too rich?

[scootermcq]

Airscrew, Fuel screws, lol

Ah man... now I'm all messed up. I thought it was the A/F screw.

[Blaine]

Proper name is Pilot mixture screw. Just saying.

[Spitfire]

Glad you posted that, I was almost afraid to mention it. Doesn't CHANGE Air/Fuel ratio at all if my understanding is correct. It actually controls how much of a air/fuel MIX enters the carburetor and is part of the slow circuit. This according to the service manual.

[Blaine]

Glad you posted that, I was almost afraid to mention it. Doesn't CHANGE Air/Fuel ratio at all if my understanding is correct. It actually controls how much of a air/fuel MIX enters the carburetor and is part of the slow circuit. This according to the service manual.

Correct.

[Herb]

Glad you posted that, I was almost afraid to mention it. Doesn't CHANGE Air/Fuel ratio at all if my understanding is correct. It actually controls how much of a air/fuel MIX enters the carburetor and is part of the slow circuit. This according to the service manual.

Correct.

Not sure which manual you are using, but...

It isn't completely correct. The screw, more or less, controls the actual air/fuel mixture, the amount of air is controlled by the size of the idle air jet at the back of the carb.

When it is an air screw (before the slide) it controls how much air enters through the idle circuit, the circuit controls the amount of fuel drawn in relation to the amount of air with the idle jet.

When it is a fuel screw (after the slide) it controls how much fuel is drawn into the air stream, the amount of air is controlled by the size of the idle air jet.

Watch the vidio.

http://www.thejunkmanadv.com/how-to-idl ... tment.html

[kidastra]

why don't any of these videos show the bike popping when they adjust the screw? And why don't any videos show the adjustment being more then a half turn (I had 2.5 full turns in.

I can't ride the bike until the snow is gone to test

[Blaine]

why don't any of these videos show the bike popping when they adjust the screw? And why don't any videos show the adjustment being more then a half turn (I had 2.5 full turns in.

I can't ride the bike until the snow is gone to test

A lot of bikes that have factory pipes you can't hear the popping.Most pop a little because they are set so lean from the factory.The stock exhaust hides that.The adjustment is already set at 2 to 2 1/2 turns & by adjusting a 1/2 is usually rich enough to eliminate any popping.