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Discussion Starter #1
I'm ready to put my rebuilt carbs back together and then sync them.
I bought the stuff to make the manometer based of this design:
http://www.powerchutes.com/manometer.asp
I bought 10' of 1/4" tubing though...do I need 12' or 1/8" like it says?

Anyway, I read on the Verses how to sync the carbs ( http://www.vn750.com/forum/showthread.php?t=1084 ), but I'm a bit confused still. I did the earshave too, so not sure if that makes anything different.

It says to get a 1/4 barbed "T" shaped connector with the base of the "T" connecting to the vacuum hose coming off the petcock...I got that part no problem.
Can someone clarify what to do next?
I believe I take a short piece of tubing from one of the remaining "T" ports and run it to the front carb vacuum port. Then I connect one end of the manometer tubing to the other "T" port and the other end of the manometer tubing to the rear vacuum port?

I just want to make sure I got everything hooked up right before I try this.
Thanks for your help
 

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It says to get a 1/4 barbed "T" shaped connector with the base of the "T" connecting to the vacuum hose coming off the petcock...I got that part no problem.
Can someone clarify what to do next?
I believe I take a short piece of tubing from one of the remaining "T" ports and run it to the front carb vacuum port. Then I connect one end of the manometer tubing to the other "T" port and the other end of the manometer tubing to the rear vacuum port?

I just want to make sure I got everything hooked up right before I try this.
Thanks for your help
Yeah you got it.

The "T" just allows the petcock to still work. The tubing length from the manometer to the "T" and rear carb should be close to equall for the most accurate reading.

Perhaps you should even reduce the front side manometer hose length by the length from the "T" to the carb. But this is probably negligable.
 

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If you get a syringe from a vet to fit that 1/4" hose, you can create a small vacuum source to the petcock and not worry about the "T".
I`ve also heard that the carb bowls hold enough gas to sync them without the vacuum hooked up to the petcock.
Maybe run for 3-4 minutes at an idle just on the gas in the bowls.
 

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Discussion Starter #5
Yeah you got it.

The "T" just allows the petcock to still work. The tubing length from the manometer to the "T" and rear carb should be close to equall for the most accurate reading.

Perhaps you should even reduce the front side manometer hose length by the length from the "T" to the carb. But this is probably negligable.
I'm still a bit confused on the tube lengths...the tube on the manometer is 10' long...So are you saying I should have another 10' of tube to go from the "T" to the Front Carb vacuum port to match the 10' of tube on the manometer?
 

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Discussion Starter #6
Okay...so in an attempt to fully understand this process, I have drawn up what I "think" is the correct way to do this. Please don't laugh at my horrible drawing abilities...so if someone can confirm this is correct, and if the line from the "T" to the front carb vacuum line needs to match the length of the Manometer tubing...Thanks.
 

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I'm still a bit confused on the tube lengths...the tube on the manometer is 10' long...So are you saying I should have another 10' of tube to go from the "T" to the Front Carb vacuum port to match the 10' of tube on the manometer?
No No,

I'm just saying the tube length from the oil level to each carb should be about equal. More air volume between the manometer and carb on one side could throw off the values.

I'd actually try it like OlHoss suggested. Just run it off the fuel in the carbs, and scrap the "T". If it runs out of fuel before you are done adjusting, just fill em up again.
 

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Okay...so in an attempt to fully understand this process, I have drawn up what I "think" is the correct way to do this. Please don't laugh at my horrible drawing abilities...so if someone can confirm this is correct, and if the line from the "T" to the front carb vacuum line needs to match the length of the Manometer tubing...Thanks.
Your diagram looks right.

The tube length is not important. I just make it long enough so I can hang the manometer off the handlebar so I can watch it while adjusting.

Just in case it's way off when you start it, watch the 2 cycle oil as it will get sucked into one of the carbs pretty fast (don't ask how I know).

You can run it off the fuel bowls for a few minutes, but it takes me longer than that to get anything done!

Jon
 

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when syncing are you just looking for even liquid while idling?
Yes the goal is to have even vaccuum across both cylinders
 
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Yes the goal is to have even vaccuum across both cylinders


Okay I read on another topic in this forum a guy saying something about checking at 4300-4800 rpm.

But as long as I get an even idle vacuum I should be good. I didn't change any jets just cleaned everything.


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Okay I read on another topic in this forum a guy saying something about checking at 4300-4800 rpm.

But as long as I get an even idle vacuum I should be good. I didn't change any jets just cleaned everything.


Sent from my iPhone using Tapatalk
Sync is done, by the book, at idle.

Some like to rev it and make sure it stays even through the rev range.

I balance for idle, as do most.
 
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Sync is done, by the book, at idle.



Some like to rev it and make sure it stays even through the rev range.



I balance for idle, as do most.


Okay thank you so much very helpful going to try it this weekend when I am off


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