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Need help guys and gals - synching my carbs

Grizz's sync tool works perfectly on my 06 Vector. Made it out of what I had laying around my garage, so didn't cost me a cent. It couldn't be simpler to use. Carbs #1 & #2 are synced with carb #3. Do not sync carbs #1 & #2 with each other. #3 cannot be adjusted, so you have to sync the other two carbs with it. By syncing #1 & #2 with each other will through the sync out with #3. Don't over think it, that's just the way it is. KISS rule. If A=C, and B=C, then A=B.
 

Grizz's sync tool works perfectly on my 06 Vector. Made it out of what I had laying around my garage, so didn't cost me a cent. It couldn't be simpler to use. Carbs #1 & #2 are synced with carb #3. Do not sync carbs #1 & #2 with each other. #3 cannot be adjusted, so you have to sync the other two carbs with it. By syncing #1 & #2 with each other will through the sync out with #3. Don't over think it, that's just the way it is. KISS rule. If A=C, and B=C, then A=B.

I know, it's worked perfectly for me too! But I forgot "how" to use it. I don't ever remember pulling off the short "pulse line" from the fuel pump on the fixed carb, #3. But my memory really sucks since I had my stroke 3 years ago.

OK, it makes total sense to synch Carbs 1 and 2 to #3 carb. So which hose goes on #3 (fixed) carb? The hose with the tee in it? Then the hose without the tee will go to 2, then ultimately to 1?
 
First, we need someone to confirm carb #3 is actually the carb that has the 'short pulse line from the fuel pump'. He stated carb #3 was stator side so if I'm understanding that correctly, that would make the carb closes to the fuel pump as #1 and then going from left to right in his picture would make carb #2 in the middle and carb #3 on the far right which also coincidently doesn't have a vacuum line from the fuel pump going to it; again judging by the pictures in that post. Since I'm not familiar with the 3 cylinder engines but they are similar to the 4 cylinders, those stock black hoses going from the carbs to the fuel pump are just vacuum lines to run the fuel pump. If you didn't use a T to be able to connect both the hose going to the fuel pump and the hose going to your sync tool, you would not be supplying the fuel pump with sufficient vacuum to supply fuel to the carbs which means you would only have time to sync the carbs until you ran all the fuel of the float bowls. Judging by the pics in his post, it appears that only what I believe to be carb #1 and carb #2 have vacuum lines going to it so when disconnecting each one so as to be able to connect your hose from the sync tool, you would also need to use the T to supply adequate vacuum to the fuel pump. Therefore, the hose without the T would always stay connect to what I believe is carb #3 (i.e. far right one in the pic) and you would use the hose with the T when connecting the hose from your sync tool to what I believe is carb #1 and carb #2 when sync'ing each to carb #3
 
First, we need someone to confirm carb #3 is actually the carb that has the 'short pulse line from the fuel pump'. He stated carb #3 was stator side so if I'm understanding that correctly, that would make the carb closes to the fuel pump as #1 and then going from left to right in his picture would make carb #2 in the middle and carb #3 on the far right which also coincidently doesn't have a vacuum line from the fuel pump going to it; again judging by the pictures in that post. Since I'm not familiar with the 3 cylinder engines but they are similar to the 4 cylinders, those stock black hoses going from the carbs to the fuel pump are just vacuum lines to run the fuel pump. If you didn't use a T to be able to connect both the hose going to the fuel pump and the hose going to your sync tool, you would not be supplying the fuel pump with sufficient vacuum to supply fuel to the carbs which means you would only have time to sync the carbs until you ran all the fuel of the float bowls. Judging by the pics in his post, it appears that only what I believe to be carb #1 and carb #2 have vacuum lines going to it so when disconnecting each one so as to be able to connect your hose from the sync tool, you would also need to use the T to supply adequate vacuum to the fuel pump. Therefore, the hose without the T would always stay connect to what I believe is carb #3 (i.e. far right one in the pic) and you would use the hose with the T when connecting the hose from your sync tool to what I believe is carb #1 and carb #2 when sync'ing each to carb #3

Appreciate all of your help Rob! Respectfully, I don't know if it matters which is is carb 1 and carb 3. We just need to stay consistent. And honestly I lost you in your above comments....but that's easy for me to do! LOL!!

The carb with the short vacuum hose is the "fixed" carb with no adjusting screw. The middle are farthest to the right (while sitting on t he sled) carbs have adjustment screws.
 
#3 carb (stator side) is preset so you sync 1 and 2 to it. There are only two screws to adjust (3 screws on 4 cylinder engines) which are located between 1-2 and 2-3.

According to grizztracks, carb #3 is the preset carb, so I would think it does matter which carb is #1 and which carb is #3 as you only want to sync carb #1 and #2 to carb #3. If we don't know for sure which is carb #3, you could potentially be using carb #1 as the preset carb and ultimately be sync'ing #1 to #2 which thrasher confirmed you do not want to do.

Additionally, grizztracks stated that the two screws are located between #1 and #2 and between #2 and #3. I'm sticking with the farthest right carb (ie the one closest to the stator and furthest from the fuel pump) being #3 so this would make carb #1's adjustment screw to be between #1 and #2 and the adjustment screw for carb #2 to be between #2 and #3. As for carb #3, there would be no adjustment screw to the right of that carb since it is the preset one.

I will admit that I don't have a service manual to confirm the carb/cylinder orders for these 3 cylinder engines so I could be way off base here and am interpreting his instructions incorrectly.
 
Since you are a VIP member you can contact a mod and request a service manual.
 
I have little doubt that the "fixed" carb is the one closest to the fuel pump. Well, honestly I'm not sure of anything anymore. Call it #1 or #3, whatever you want.
 
Now I'm thinking the fixed carb is the one farthest away from the fuel pumps? As that carb had the idle adjustment screw? I dunno!!!!!
 
Although this is from my Apex service manual for a 4 cylinder engine, I would think the 3 cylinder would have the same order minus a cylinder:

4cylinderorder.JPG
 
Ok, let's try this once again. I think that I see why there is some confusion. In grizztarcks pics of how to sync the carbs, there is one line attached to carb #3, and one vacuum line with the tee attached to carb#2, but his screwdriver is actually syncing carb #1. Just probably a mistake when he took the picture. So, carb#1 is the carb next to the fuel pumps, and carb #3 is the carb at the other end, with carb#2 being in the middle. There are two syncing phillips head screws. For carb#1, the screw is between carb#1 and carb#2. For carb#2, the screw is between carb#2 and carb #3. There is no syncing screw for carb #3. Now attach the hose without the tee junction to the vacuum port on carb #3(covered by a black cap), the hose with the tee goes to the vacuum port on carb#2 as shown in grizztracks pics. With engine running adjust the sync screw between carb#2 and carb#3 to adjust carb#2(fluid to the same level on each side) . Once synced, now do the same for the vacuum lines to carb#1, sync to carb#3 by adjusting the screw between carb#1 and carb#2. Attach all hoses and caps back to their original spots. You are done. Ride and enjoy.
 
Hose connections are shown for adjusting carb #2 to the preset carb #3.
For this configurations adjust screw #2 until the sync tool is balanced then reinstall #2 fuel pump vacuum hose to the carb.
Move the T-hose over to #1 carb , reconnect the #1 fuel pump vacuum hose to the "T" and sync #1 carb to #3 preset carb by adjusting the #1 screw.

carb sync diagram 1.jpg
 
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Hose connections are shown for adjusting carb #2 to the preset carb #3.
For this configurations adjust screw #2 until the sync tool is balanced then reinstall #2 fuel pump vacuum hose to the carb.
Move the T-hose over to #1 carb , reconnect the #1 fuel pump vacuum hose to the "T" and sync #1 carb to #3 preset carb by adjusting the #1 screw.

View attachment 158883

THANK YOU SIR!!!!
 
My carbs are synched! WOO HOO!!!! LaLaLa
 
Were they out much? I synched mine years ago, and about every other year I check them and they haven't required adjustment. I will check them again this year once I get my sled put back together. There is no snow here in MI to speak of, and restaurants are all closed until Feb 1, so no riding yet. I purchased a carb synch tool about a dozen years ago and have been using that. It is the Morgan Carbtune model and it works well, but I haven't heard anything bad about the home-made ones.
 
Were they out much? I synched mine years ago, and about every other year I check them and they haven't required adjustment. I will check them again this year once I get my sled put back together. There is no snow here in MI to speak of, and restaurants are all closed until Feb 1, so no riding yet. I purchased a carb synch tool about a dozen years ago and have been using that. It is the Morgan Carbtune model and it works well, but I haven't heard anything bad about the home-made ones.

#2 way wayyyyyy off! The other carb was fairly off, but not near as bad as #2.
 


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