Mixture. - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
Carbs and Fuel System
From the gas tank to the carbs
All fuel system discussion

Reply
 
LinkBack Thread Tools Display Modes
post #1 of 34 (permalink) Old 06-11-2016, 10:24 AM Thread Starter
Member
 
Join Date: Dec 2014
Location: Berwick pa
Posts: 78
iTrader: (0)
 
Mixture.

There are so many posts on here it just takes too long to find what i am looking for so I created one i assume had been created many times before. Simple question. What is factory screw turn out on mixture? Is it a whole 3 turns around or 3 half turns? I know one side gets a little more on than the other, least I think I read that. I've jetted and done everything you could imagine to my bike in mods but I just can't run it with air filters on. Bogs out. Used the thinnest micro material and all I could get was up to 7000 rpm before it bogs out. Not even close to red line. Mess screen is all that works. So the obvious problem is mixture. Mixture I have now is close to 4 out on both sides, full turns. With no filters on though, it f***ING moves. Rear wheel just sits there and spins if I choose to burn it.

Last edited by ridgegilt; 06-11-2016 at 10:25 AM. Reason: Misspelled and didn't want to sound like a tart.
ridgegilt is offline  
Sponsored Links
Advertisement
 
post #2 of 34 (permalink) Old 06-11-2016, 10:51 AM
Senior Member
 
Spockster's Avatar
 
Join Date: Nov 2012
Location: WV
Posts: 7,302
iTrader: (5)
   
Idle air mixture screws won't do anything above idle.

What size jets do you have? You let more air in through the wire mesh, so it's able to run the rich mixture, if my guessing on your jets is correct.

What do the plugs look like?

2003-21k mi
Shaved w/UniPK92+Stock Jets-TPE/MOSFET-Shinko Tires-AGM batt-bags-chrome-LEDs...more
__________________________________________________ ____________
Repair Manual: http://www.mediafire.com/file/mj7z81..._Catalogue.pdf

Owner's Manual: http://www.mediafire.com/file/nscb5f...ers+Manual.pdf
Spockster is offline  
post #3 of 34 (permalink) Old 06-11-2016, 11:24 AM Thread Starter
Member
 
Join Date: Dec 2014
Location: Berwick pa
Posts: 78
iTrader: (0)
 
https://drive.google.com/folderview?...TM1bzFHNU1kSnM

They look good but the two that are down in the deep holes I have never replaced in 2 yrs since I got the bike. They won't come out with any type socket. Little wet on the plugs but only on the threading not the tips.
ridgegilt is offline  
 
post #4 of 34 (permalink) Old 06-11-2016, 11:58 AM
Old Fart
 
Knifemaker's Avatar
 
Join Date: Jun 2004
Location: Catawissa, MO
Posts: 11,786
iTrader: (4)
     
Garage
Yes, Fuel screws only really effect idle. Turning them out adds more fuel, turning in leans the mixture. If the bike runs fine without the air filters, I'd say it's running rich....however, be sure the air filter is NOT blocking the small holes on the mouth of the carbs.... Some have a ridge that can do this on the inside of the rubber of the filter.

What size jets are you using? Sounds like your main is too big.

BTW- Stock position of the "air screw" is 1-1/8 to 1-1/4 turns out.
And I would try to get those other plugs out and replace all four with te NGK Iridiums....

If You Are Not Sure If I Am Joking or Not....I AM !!Photos:
http://www.flickr.com/photos/knifemaker1954/sets/

Last edited by Knifemaker; 06-11-2016 at 12:01 PM.
Knifemaker is online now  
post #5 of 34 (permalink) Old 06-11-2016, 12:00 PM
Senior Member
 
Spockster's Avatar
 
Join Date: Nov 2012
Location: WV
Posts: 7,302
iTrader: (5)
   
I'm confused, since you originally posted :

Edit: Ok, I mistook that it was the jets you couldn't get out, but you were talking about the plugs. They look a tad rich.

Quote:
I've jetted and done everything you could imagine to my bike in mods but I just can't run it with air filters on.
When you have actual filters on it, what brand/model are they?

Where is your carb vent?

2003-21k mi
Shaved w/UniPK92+Stock Jets-TPE/MOSFET-Shinko Tires-AGM batt-bags-chrome-LEDs...more
__________________________________________________ ____________
Repair Manual: http://www.mediafire.com/file/mj7z81..._Catalogue.pdf

Owner's Manual: http://www.mediafire.com/file/nscb5f...ers+Manual.pdf

Last edited by Spockster; 06-11-2016 at 12:03 PM.
Spockster is offline  
post #6 of 34 (permalink) Old 06-11-2016, 12:08 PM Thread Starter
Member
 
Join Date: Dec 2014
Location: Berwick pa
Posts: 78
iTrader: (0)
 
Off hand I think it's either 140 or 142-145?? I had rejected before I removed the air box crap and it ran very well aside from some snap crackle and pop on deceleration with KN air filters. Oval shape ones. I have straight pipes now and the intake has the original rubber boots and I made two tube filters that wedge in the boots. Basically open through intake and exhaust. ThE straight pipes were put on later so whether they were on or semi stock ones were on, it still won't run with filters. So the only difference from when it worked with filters to now is I got rid of the air box. Jets probably too big than so that means it's running to rich? It's crazy how one thing removed, such a simple thing, could have such an effect. Been running with these jets for nearly 2 yrs. Every ones advice is appreciated and please keep up with ideas and tips.
ridgegilt is offline  
post #7 of 34 (permalink) Old 06-11-2016, 12:19 PM Thread Starter
Member
 
Join Date: Dec 2014
Location: Berwick pa
Posts: 78
iTrader: (0)
 
https://drive.google.com/folderview?...VpuRHQ0RFB1Sms

Breather is unobstructed and mess screen over it to keep large debris away.

Carb vent.
ridgegilt is offline  
post #8 of 34 (permalink) Old 06-11-2016, 12:28 PM Thread Starter
Member
 
Join Date: Dec 2014
Location: Berwick pa
Posts: 78
iTrader: (0)
 
Luckily if it just needs rejetted to a size smaller, it will only take 10mins to do. Amount of times I've worked on this I have learned how to take it apart with ease and no wasted time.
ridgegilt is offline  
post #9 of 34 (permalink) Old 06-11-2016, 12:46 PM
Old Fart
 
Knifemaker's Avatar
 
Join Date: Jun 2004
Location: Catawissa, MO
Posts: 11,786
iTrader: (4)
     
Garage
Well, I think trying a smaller jet for the mains would be the first step I'd make trying to sort this out.
Let us know what happens...

If You Are Not Sure If I Am Joking or Not....I AM !!Photos:
http://www.flickr.com/photos/knifemaker1954/sets/
Knifemaker is online now  
post #10 of 34 (permalink) Old 06-11-2016, 04:19 PM Thread Starter
Member
 
Join Date: Dec 2014
Location: Berwick pa
Posts: 78
iTrader: (0)
 
I had 142 main jets in. I put 140 ones in and what happened you ask. I got immense power in acceleration....without filters. Filters on, bogs out at 5-6000rpm. Worse than before. It's a puzzling issue. I'll leave those jets in. For now I'll just continue running without micro fiber between my screens on the filters. At least the filters sit inbetween under the gas tank. I know they are fairly protected there since I was caught in the rain already and no issue of water getting in. If anyone has any other ideas I am all ears.
ridgegilt is offline  
Sponsored Links
Advertisement
 
Reply

Bookmarks

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

Once registered, your User Name"cannot be changed". We can make exceptions within 7 days, but after that, it is set in stone.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome