Synced carbs, idle now 3K-4K

[jetmechmarty]

I need one of those tools! Nobody near me could do the job. I drove 70 miles to my friends shop. He could have messed it up. These things happen. I can't call him and bitch because he did it for free.

I'm trying to figure out what went wrong. I had them way out of wack when I went down there. At least I could decelerate.

[CaptonZap]

.

So, do you think I'm going to have to take the butterfly shaft apart on 3 & 4?

As they taught in A&P school, a good visual inspection will go a long way in trouble shooting.
Take the carbs off the bike, and look in the side that goes next to the engine.
If the sync is off, the butterfly's will not all have the same clearance between their bottom edges and carb bore. You can also observe how the linkage is working, and see if it is hanging up.
If one of the shaft seals was intercoursed up during installation, it might cause the observed symptoms.
If all looks well, there's no sense it taking them apart. Before you take them off, get the fault to happen, and while it is running, squirt some heavy oil down onto the shafts where they come through the carb body. If one sael is screwed, the oil should seal it enough to make a noticable difference in idle speed.

Ah haw, I hadn't read your post stating;
"Nothing was touched, but the sync screws. Mixtures were left alone. It was real quick, in and out. I popped off the tank and he synced it up. We used only the fuel that was in the bowls. I put it back together and off I went.
__________________
Marty (in Georgia) "

I'll side with Greg on the sync. As the fuel level went down, it changed the internal dynamics of the carb, and end settings were probably less than optimal.
It still may be a mechanical problem with the linkage and carb, but without a good visual inspection, you won't know.
Bite the bullet, take them off, and look them over. The sync linkage will be readily observable, and you can look for any faults in it's operation.
If all looks well, reinstall them, and figure out a method to sync them while they get a supply of gas, just as they would get when normally operating
CZ

[jetmechmarty]

OK Captain. I'll do it, but not tonight. I've moved on to a glass of merlot and a fine cigar.

[LuckyEddie]

carbs

Marty,
I notice in an earlier reply that you also replaced the main jets.
Same size? You stated that it ran fine before needle and seat leaked.
Everything affects everything......

[BA80]

Marty,
I notice in an earlier reply that you also replaced the main jets.
Same size? You stated that it ran fine before needle and seat leaked.
Everything affects everything......

Mains won't affect the idle in any way Eddie.

[jetmechmarty]

The main jets are now bigger, but what does that have to do with idle? I thought they had nothing to do with it. The machine runs great with the throttle open.

[jetmechmarty]

Greg types with all of his fingers.

[BA80]

Greg types with all of his fingers.

Nope, just 2.....

[bikerphil]

Marty, do yourself a favor and purchase some sync gauges. If you and your friends work on your own bikes, it's a must have tool. I myself don't fool with the type that uses fluid, they are a hassle. JMHO.

By chance, is your #3 carb boot clamp interfering with the throttle linkage at the carb? The screw on the clamps should be at the bottom of the boots, not on top, they can interfere that way, JAT.

[jetmechmarty]

Phil, you are right. I've been putting it off. Ordering one now means next month for me.

[tweeleft]

did you put the throttle cable back in the holder at the carbs? I had that issue

[jetmechmarty]

did you put the throttle cable back in the holder at the carbs? I had that issue

Funny you should ask. The first time I stopped on the way home, I looked and "Ah HA". The throttle cable was out of the clamp and sideways at the carbs. I fixed it, but it did not solve the problem.

[GLoweVA]

Marty, to me it sounds like a linkage type issue. If you can push down on #3/4 and the idle drops back down then it sound like the butterflies aren't shutting all the way after you open up the throttle.
If it idles fine at 1K (after you push them down) then it sounds like your sync is good and there are no vac leaks.

Like some have said, take them off and look at how those suckers open/close.
Maybe the last time you had them out and back in again, something got rearranged like phil says about the boot clamp.

[skids]

Nothing was touched, but the sync screws. Mixtures were left alone. It was real quick, in and out. I popped off the tank and he synced it up. We used only the fuel that was in the bowls. I put it back together and off I went.

I dare say that it is impossible to get a descent synch for carbs with only the fuel in the bowls! You need to either run a line(s) to the tank or get an auxiliary tank.

[James England]

I dare say that it is impossible to get a descent synch for carbs with only the fuel in the bowls! You need to either run a line(s) to the tank or get an auxiliary tank.

You are correct. You need to use extra long fuel lines with the tank off the bike. It is impossible to sync carbs correctly on the fuel that's in the float bowls only