Need help guys and gals - synching my carbs

[4strokeluvr111]

I have a 2005 Vector with 20K+ miles. I built a synch tool (shown) back in 2007 that Grizztracks recommended and have used it for the past 15 years. Problem is that it's been a couple years since I used it and my memory sucks. I found the thread where he showed how to use it but I'm still doing something wrong. My carb synch is really effed up now and I need to get it fixed.

To try to get a baseline, I turned in both carbs screws all the way till seated, then backed out X times. Ran the sled and then backed out the screws a little more (each the same amount) to where the sled sounded OK. I tried emailing Grizztracks but I don't know if he's around here anymore and haven't gotten a reply from him.

So I went on Amazon and ordered this and it will arrive 1/21/21: https://www.amazon.com/gp/product/B07MQL9DS7/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1
I saw something similar at Harbor Freight yesterday and I just might go buy it.

I need to get the sled carb's synched up before a ride on Saturday. Any help, comments, thoughts.....anything to get me back on track would be most appreciated!

 

[RobX-1]

I was going to build one of those too but ended breaking down and purchased a mercury Motion-Pro 4 carb sync'er. Although the instructions I posted in this post #29 (https://ty4stroke.com/threads/just-...o-before-snow-fall.160887/page-2#post-1547580) applied to a 4 cylinder, it might help with your process.

 

[4strokeluvr111]

I was going to build one of those too but ended breaking down and purchased a mercury Motion-Pro 4 carb sync'er. Although the instructions I posted in this post #29 (https://ty4stroke.com/threads/just-...o-before-snow-fall.160887/page-2#post-1547580) applied to a 4 cylinder, it might help with your process.

I thought about buying a Motion Pro but like always "I need it now!". I live in a small town and there's no place that stocks a Motion-Pro. They can order it sure, but that doesn't help me now.

 

[TPAY243]

Make sure your carbs are clean before you start the sync. Process if they are dirty or plugged somewhere it will throw everything off.

 

[Snorunner]

I have had good luck with a Uni-Syn Carb tool. Cheap and easy to use. You can google it.

 

[kinger]

I'm looking at the service manual for the RX1 and it says warm up the engine and make sure it idles at 1350 + or - 100 rpm. Yours good here not sure on vector? Then it says your ignition timing should be checked. Leading me to believe if that is whacky you could be chasing your tail. Then it says sync the carbs in the middle to each other, reving it a second or two in between adjustments making sure your gauge is reading the same. Then same thing for carb 3 to 4 and 2 to 1. Difference between carbs should not exceed 0.19 psi. Lastly measure your idle speed and adjust accordingly.

 

[thrasher]

I have a 2005 Vector with 20K+ miles. I built a synch tool (shown) back in 2007 that Grizztracks recommended and have used it for the past 15 years. Problem is that it's been a couple years since I used it and my memory sucks. I found the thread where he showed how to use it but I'm still doing something wrong. My carb synch is really effed up now and I need to get it fixed.

To try to get a baseline, I turned in both carbs screws all the way till seated, then backed out X times. Ran the sled and then backed out the screws a little more (each the same amount) to where the sled sounded OK. I tried emailing Grizztracks but I don't know if he's around here anymore and haven't gotten a reply from him.

Here is the original thread. This may get you back on track.

https://ty4stroke.com/threads/carb-sync-tool.108472/

 

[thrasher]

Here's grizztracks original thread on how to use his tool to sync the carbs. Have used it and followed his directions, and it works well.

https://ty4stroke.com/threads/carb-sync-tool.108472/

 

[RobX-1]

Those are much better than mine since it's applicable to the 3 cylinder. As for trying to get a baseline, isn't the objecting with sync'ing the carbs is to get them registering the same on the sync tool as opposed to some specific measurement. Therefore, I would think the OP would just want to connect the hoses to carb #1 and #3 and turn screw until liquid in hoses are balanced and then connect the hoses to carb #2 and #3 and repeat.

 

[4strokeluvr111]

Here's grizztracks original thread on how to use his tool to sync the carbs. Have used it and followed his directions, and it works well.

https://ty4stroke.com/threads/carb-sync-tool.108472/

Thanks Thrasher. This is the post I found but are still confused. I see that #2 carb (the middle one) is connected to the line that has the Tee in it (going to the fuel pump). When you adjust #1, do you move the line with the Tee in it to #1? And the line without the tee to #2?

This is what's got me confused.

 

[RobX-1]

The way I read Grizzztracks’ post is that the number three carb is the pre-sync one so that you wanna sync your carb number 1 to 3 and your carb number 2 to 3. in his pictures he’s sync’ing carb number two first; that’s why you see the two hoses going to two and three and he’s using the adjustment screw between two and three to adjust carb two. what he doesn’t show you is the hose is going to carb one and three and using the screw between carb one and two to sync carb one. hope that helps

 

[thrasher]

The way I read Grizzztracks’ post is that the number three carb is the pre-sync one so that you wanna sync your carb number 1 to 3 and your carb number 2 to 3. in his pictures he’s sync’ing carb number two first; that’s why you see the two hoses going to two and three and he’s using the adjustment screw between two and three to adjust carb two. what he doesn’t show you is the hose is going to carb one and three and using the screw between carb one and two to sync carb one. hope that helps

That's correct. Sync carb #1 with carb#3, then carb#2 to carb#3, or in whatever order to the control carb#3, as it cannot be adjusted. Hose needs to be moved between #1 and #2 carbs when adjusting them, but always leave one hose attached to carb #3.

 

[4strokeluvr111]

But the vac line on carb 3 is never removed in the pictures? On carb 3, the vac (pulse) line is the short hose coming from the top fuel pump. Something not right. I've got 1 nd 2 synched to each other but the sled idles like crap.......because the carbs arent synched to #3! I wish Grizz was around to set me straight.

 

[RobX-1]

In that post, he states carb #3 is stator side so that second picture of two hoses would be going to carb #2 and carb #3. Unless I am reading/viewing this wrong, that would make carb #1 with the short hose to the fuel pump. If this order is correct, it sounds like you are sync'ing the two non-preset carbs (i.e. carb #1 and #2) to each other which would explain the rough idle. I will admit the pictures are a little confusing because second pic states he is syncing carb #2 but then in fourth pic it shows him adjusting the screw between carbs #1 and #2. Since I've only had to sync 4 cylinders and with success, I may not be the appropriate person to interrupt this.

 

[RobX-1]

That's also why I love my four hose sync tool as you can get all 3 or 4 carbs connected at once and then make the appropriate adjustments but still using the master or preset carb to do so.