Shotgun complete, A/F (sorta) adjusted, carb syncing question

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mundmc

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Where I left off, the "shotgun" fixed my bad idle/ low power question.

Today I decided to try to sync the carbs and to futz with the air-fuel screws.

1) Even if I tightened the screw for carbs 3&4 all the way, they still wouldn't go to the same vacuum. Thoughts?
471178a8205e5778a37dacf46f457e72.jpg


2) Tightening the air-fuel screw of carb 3 all of the way didn't appear to kill the cylinder. Side-bar, I have no idea how by the a-f screw for carb 1 is now missing (it was previously 3 and 3/4 turns out)

3) Even though she ran MUCH better at idle and was less klunky going into gear, she took longer than usual for her rev's to come down when I rolled off of the throttle, which was initially startling

4) Lastly, where can I buy socket bolts for the carb covers, scoops, and intake duct cover screws, AND a new air-fluid screw/spring/ washer assembly AND rubber lugs to plug their hole???


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Where I left off, the "shotgun" fixed my bad idle/ low power question.

Today I decided to try to sync the carbs and to futz with the air-fuel screws.

1) Even if I tightened the screw for carbs 3&4 all the way, they still wouldn't go to the same vacuum. Thoughts?
471178a8205e5778a37dacf46f457e72.jpg


2) Tightening the air-fuel screw of carb 3 all of the way didn't appear to kill the cylinder. Side-bar, I have no idea how by the a-f screw for carb 1 is now missing (it was previously 3 and 3/4 turns out)

3) Even though she ran MUCH better at idle and was less klunky going into gear, she took longer than usual for her rev's to come down when I rolled off of the throttle, which was initially startling

4) Lastly, where can I buy socket bolts for the carb covers, scoops, and intake duct cover screws, AND a new air-fluid screw/spring/ washer assembly AND rubber lugs to plug their hole???


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""I have no idea how by the a-f screw for carb 1 is now missing (it was previously 3 and 3/4 turns out)""
Are you saying this a/f mixture screw is missing? You won't be able to get them all the same without it.
Dannymax at BRC at the top or bottom on any page here has the carb screws a/f mixture screws and rubber plugs for the a/f holes and the jip screws for the intake covers are at boats.net fo $3-$4.
 
I just checked in with Dannymax and await his reply. I am confused though, as I'm missing my a/f screw for carb 1, and its carbs 3&4 that won't equilibriate. Thank you, as always, for your help!


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I just checked in with Dannymax and await his reply. I am confused though, as I'm missing my a/f screw for carb 1, and its carbs 3&4 that won't equilibriate. Thank you, as always, for your help!


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They are still not going to sync correctly until you get the a/f mixture screw in.
The only other time i have seen them where 3&4 wouldn't match up was bent tabs that the sync screws are touching.
 
To hear a change from screwing in an A/F screw, the carbs have to be in good sync. The idle turned down low, and the pilot circuits clean.
The carb you have that is missing the A/F needle? Make sure you locate the washer spring and o-ring. The O-ring tends to stick in the tunnel. It's difficult to see. But you can usually fish it out with a thin straw. Like a cocktail straw or the straw that comes with carb clearer cans.
 
Dan, if you would like to cover shipping and a little labor send your carbs up, I will have a look at them, put them on the test engine and see what the situation is. All you would need to do is re-sync and fine tune the a/f screws to your engine.
 
Dan, if you would like to cover shipping and a little labor send your carbs up, I will have a look at them, put them on the test engine and see what the situation is. All you would need to do is re-sync and fine tune the a/f screws to your engine.
Wow, nice offer! :clapping:
 
Dan, if you would like to cover shipping and a little labor send your carbs up, I will have a look at them, put them on the test engine and see what the situation is. All you would need to do is re-sync and fine tune the a/f screws to your engine.

PM'd you.

Anybody have thoughts on why my bike is rev'ing longer than typical when I roll off the throttle? It is similar (but not nearly as bad) as riding with the choke on.
 
PM'd you.

Anybody have thoughts on why my bike is rev'ing longer than typical when I roll off the throttle? It is similar (but not nearly as bad) as riding with the choke on.

A/F at idle most likely not set right yet. Make sure the return spring snaps the throttle plates shut quickly. Cables can screw this up too. You can disconnect the cables and see if they're the issue with that.
Steve-o
 
If they are out of sync they are not all closing their venturi's(butterflies) at the same time. This means one or two and maybe three are staying open longer.
 
PM'd you.

Anybody have thoughts on why my bike is rev'ing longer than typical when I roll off the throttle? It is similar (but not nearly as bad) as riding with the choke on.

If you have a A/F screw missing it's running lean on that cylinder which means it's idling fast. So it's working against the other cylinders when trying to slow down.

Dave
 
If you have a A/F screw missing it's running lean on that cylinder which means it's idling fast. So it's working against the other cylinders when trying to slow down.

Dave



Ahhhhhh, I think I see now.


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Update:
- Did a second shotgun and pea shooter for good measure
- Replaced the missing a/f screw (thank you dannymax!)
- re-synced the carbs properly
3df1ce99953f6693fa2ab77dbbb27afb.jpg

- tweaked the a/f screws
- took it for a ride

Holy cow. Smooth idle, and she freaking tore up a snooty Brooklyn neighborhood. Many car alarms work, apparently.

Next step: Installing COPs (thanks Blaxmax!)


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