How to set your a/f mixture screws manually

[blaxmax]

'They should be set as lean as possible . Set up your carbs...then take a ride and adjust one carb at a time.
With the engine at operating temperature start with one carb and turn in the mixture screw a very very small amount at a time ....turn it in a hair..then ride it .
Turn it in some more then ride on ....keep doing this until the carb starts to spit back when you accelerate or take off from a stop...then back out the screw a bit at a time till it stops spitting ....When done go to the next carb ....it takes a while to do this .
I just carried a small screw driver in my pocket for a few rides and kept working with the screws . This is how we get over 40 mpg .
When it is right the bike will be cold natured to start even in the middle of Summer and will idle smooth when warm .
I always just smile when someone tells me how well their bike is in tune because it does not need the choke to start.'

 

[Miles Long]

I've watched my good bud Toolman set the A/F screws on my bike, following a valve adjustment and/or carb sync.
He essentially does the procedure the same way as you outline, but the bike is on the centerstand, in his shop. How he hears when one cylinder is starting to stumble, over the roar of three well running cylinders, is beyond me. Must just come with experience.
- why do you prefer to do the adjustments "on the road"?
- can a stethoscope, heat gun, sound level meter, or whatever, be used to make the procedure more measurable/less arbitrary, rather than just relying on the human ear, (when on centerstand), or in your case, when the bike starts to hesitate on acceleration?
Cheers!

 

[blaxmax]

This was meant to use as a reference without a tool. Except for the screwdriver.I use a carb sync to set mine.

Manually Miles--cheers

 

[[email protected]]

Miles, blax's post is a copy paste from elsewhere. I believe what Blax is saying he thinks it's funny that the writer of the info says he knows the tune is right when he needs choke in the summer.



Sent from my SM-G900V using Tapatalk

 

[blaxmax]

Miles, blax's post is a copy paste from elsewhere. I believe what Blax is saying he thinks it's funny that the writer of the info says he knows the tune is right when he needs choke in the summer.



Sent from my SM-G900V using Tapatalk

All year round

 

[PMaxx]

I was curious what mine were set at because the caps were all removed and the bike has a Stage 1 jet kit and a Marks 4-1 exhaust. They were all set at 3.5 turns. I set them to 2.5 turns and there seems to be no bad effects...the slightest stumble at idle occasionally and that's it.
EXCEPT the fuel pump started clicking like crazy when I turned the key and does it every time now....there's no way this can be related to the mixture can it?

Here's a link to the video:

http://vid124.photobucket.com/albums/p31/81monte/IMG_1470.mp4

 

[Miles Long]

This was meant to use as a reference without a tool. Except for the screwdriver.I use a carb sync to set mine.

Blax, I'm assuming that you mean that you use an actual carb sync device(motionpro, vacuum gauges, etc), to set your individual A/F screws.
Now THAT would be a procedure I'd like to see detailed out, if you haven't posted previously.
As I probably mentioned before, if my bike seems to be running O.K., I don't mess with carbs. Too much of a "black art" to this hacker.
But I don't mind trying my hand with procedures that are well spelled out , such as carb syncing.
Taking it to the next level, setting the A/F screws using the same device, would be groovy!

 

[blaxmax]

This was meant to use as a reference without a tool. Except for the screwdriver.I use a carb sync to set mine.

Blax, I'm assuming that you mean that you use an actual carb sync device(motionpro, vacuum gauges, etc), to set your individual A/F screws.
Now THAT would be a procedure I'd like to see detailed out, if you haven't posted previously.
As I probably mentioned before, if my bike seems to be running O.K., I don't mess with carbs. Too much of a "black art" to this hacker.
But I don't mind trying my hand with procedures that are well spelled out , such as carb syncing.
Taking it to the next level, setting the A/F screws using the same device, would be groovy!

I have posted it before and will again Miles. I will do a video this time.
In the meantime after syncing with a morgan carbtune I set the a/f mixture screws to their highest vacuum on the sync then turn them back 1/8 turn.

 

[Miles Long]

I have posted it before and will again Miles. I will do a video this time.
In the meantime after syncing with a morgan carbtune I set the a/f mixture screws to their highest vacuum on the sync then turn them back 1/8 turn.

Thanks. Looking forward to the video. Doesn't sound complicated at all.
I'm sure lots of owners were not aware of this "trick of the trade"
Best if you start a new thread, so the procedure doesn't get buried in this one.
Cheersunk:

 

[blaxmax]

Will do, thanks Miles.

 

[Traumahawk]

I was curious what mine were set at because the caps were all removed and the bike has a Stage 1 jet kit and a Marks 4-1 exhaust. They were all set at 3.5 turns. I set them to 2.5 turns and there seems to be no bad effects...the slightest stumble at idle occasionally and that's it.
EXCEPT the fuel pump started clicking like crazy when I turned the key and does it every time now....there's no way this can be related to the mixture can it?

Here's a link to the video:

http://vid124.photobucket.com/albums/p31/81monte/IMG_1470.mp4

No, its not mixture related.....at the very most, it is a diaphragm that has become dislodged in the fuel pump. You can take the end off of the pump, and you will see some small diaphragms there. Them being in place is what allows the pump to build and maintain pressure.

That being said sometimes mine will click like crazy for about a mile, and does it maybe once a year, and then quits. It will go back to normal operation for the rest of the year.

 

[blaxmax]

I was curious what mine were set at because the caps were all removed and the bike has a Stage 1 jet kit and a Marks 4-1 exhaust. They were all set at 3.5 turns. I set them to 2.5 turns and there seems to be no bad effects...the slightest stumble at idle occasionally and that's it.
EXCEPT the fuel pump started clicking like crazy when I turned the key and does it every time now....there's no way this can be related to the mixture can it?

Here's a link to the video:

http://vid124.photobucket.com/albums/p31/81monte/IMG_1470.mp4

Easy to take apart- there will be 2 rubber diaphragms that have possibly flipped over. Not related to a/f mixture.If you can't get it send me a message and i will send you a new one.

 

[blaxmax]

I was curious what mine were set at because the caps were all removed and the bike has a Stage 1 jet kit and a Marks 4-1 exhaust. They were all set at 3.5 turns. I set them to 2.5 turns and there seems to be no bad effects...the slightest stumble at idle occasionally and that's it.
EXCEPT the fuel pump started clicking like crazy when I turned the key and does it every time now....there's no way this can be related to the mixture can it?

Here's a link to the video:

http://vid124.photobucket.com/albums/p31/81monte/IMG_1470.mp4

PMaxx, that fuel pump is actually acting normal.

 

[blaxmax]

Thanks. Looking forward to the video. Doesn't sound complicated at all.
I'm sure lots of owners were not aware of this "trick of the trade"
Best if you start a new thread, so the procedure doesn't get buried in this one.
Cheersunk:

Steve-o calls it "old school".

 

[sdt354]

I've watched my good bud Toolman set the A/F screws on my bike, following a valve adjustment and/or carb sync.
He essentially does the procedure the same way as you outline, but the bike is on the centerstand, in his shop. How he hears when one cylinder is starting to stumble, over the roar of three well running cylinders, is beyond me. Must just come with experience.

Cheers!

Miles,To do the ear method, which is how we were taught back in the old carb. days, the carbs need to be in sync. The idle turned down lower than spec helps too. I always get in the ballpark this way. Idle is then put back to normal and a ride with a screw drive is always taken for my adjustment. I then resync my carbs off idle, at about 1800 RPM. for a crisp throttle. My bike won't idle very smooth, but that's fine.
Steve-o

 

[hardrider]

just read this post is there a link to the video

 

[Nubicon]

'They should be set as lean as possible . Set up your carbs...then take a ride and adjust one carb at a time.
With the engine at operating temperature start with one carb and turn in the mixture screw a very very small amount at a time ....turn it in a hair..then ride it .
Turn it in some more then ride on ....keep doing this until the carb starts to spit back when you accelerate or take off from a stop...then back out the screw a bit at a time till it stops spitting ....When done go to the next carb ....it takes a while to do this .
I just carried a small screw driver in my pocket for a few rides and kept working with the screws . This is how we get over 40 mpg .
When it is right the bike will be cold natured to start even in the middle of Summer and will idle smooth when warm .
I always just smile when someone tells me how well their bike is in tune because it does not need the choke to start.'

4/18/2016

All of mine start without the choke-How about a set of cops for yours?

4/15/2016

Not me. If you tune it right you don't need to choke it.My plugs are tan.Every bike I have starts without the choke but one and it is in the pic above.

I don't choke it and it is not too rich.

4/15/2016

Yeah and yamaha has a pro stock bike too.lmao.Some people can think outside the manual.
To each their own pal.Manuals---I did need no stinking Manual.:rofl_200:

4/16/2016 (after claiming the factory startup procedure and tuning description is incorrect)

What a clown.

 

[Traumahawk]

Well He's gone.....for now. I figure that there will be a "cousin Jed" probably show up in the future.