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Soul Rider
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7 Posts
Discussion Starter #1
Hey there everyone, I have a 1986 vulcan and have had stuttering that keeps me to 5500 rpms. I was told I could replace the chrome high air filters (which weren't suggested in the first place) with the stock ones and that would eliminate the stuttering and open up the bike. 2 things, has anyone else had this problem and is putting the stock housing units back on as simple as it seems? thank you for responding!!! Ride on!:
 

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FREEBIRDS MC CENTRAL NY
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16,222 Posts
Do you mean pod filters?if all the" stuff"for the stock filters are gone it would be easier and more cost effective to 're jet the carbs.read up on the ear shave in the Vulcan verses.
 

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Jack of all trades
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2,863 Posts
Yeah man going to need some pics so we know what you are working with.
 

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Jack of all trades
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2,863 Posts
Yep rejet should fix your problem. Male sure your idle screws are set at 2.5 turns out.
 

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Soul Rider
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7 Posts
Discussion Starter #7
is there a link or video on how to rejet? I am still new at the mechanical side of the bike and am not sure whats the best route?
 

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Super Moderator
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2,570 Posts
where does the vacuum line on the right side carb go?? (3rd pic) with an earshave, it should be plugged.

vacuum line on left carb should go to the petcock (unless petcock has been replaced with a manual/non-vacuum one, in which case it should be plugged)

also, where does the carb vent hose go to? this will be 2 short lines that T into a single and it USED to go to the right side ear. without the ear, secure it under than tank, to a frame rail, on top side of rail to keep it out of turbulent air.
 

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8,245 Posts
That was one of my questions... Looks like vacuum off the right side carb is looping back to area of the carb vents. Could be a problem.
 

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Soul Rider
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7 Posts
Discussion Starter #10
Here is what I want to replace the mod filter with. I was wondering if it will just fit right on? I will look for the tubes to see where it is you were talking about and post another pic. Thank you all for your help, I am truly grateful!
 

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Jack of all trades
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2,863 Posts
If you wanted to go back to stock air filters you would need the surge tank, rubber ducts, and hoses that go with the stock air system.
 

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269 Posts
By 'stuttering' do you mean losing power? If so at what throttle position / rpm? When I went to the pod intake, my bike ran great untill I was @ 3/4 throttle and >4000 rpm. This is where the taper part of the needle circuit is losing authority and the main jet is taking up the slack. I rejetted to 135 from 132 which seems to have fixed the problem. But I have not taken the bike above 70mph so I don't know if I need to go to a 138 jet? If you are experiencing problems at lower throttle positions you might have to rejet low speed and/or different needle arraingment
 

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Super Moderator
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2,570 Posts
those are the stock ears...

you also need the stock airbox to use them (many times its mangled/destroyed during removal)

the only reason to go thru the work to put them back on is if you wish to have that look back. and on that note, no reason you cant put them on, but leave the airbox out. they would just be on their for decoration then.
 

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FREEBIRDS MC CENTRAL NY
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16,222 Posts
What exhaust are you using.I earshaved and degoated with Harley screaming eagle mufflers and needed 140 main and 40 pilots with 2 spacers under the needles. But every bike is different
 

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FREEBIRDS MC CENTRAL NY
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16,222 Posts
2 3/4 turns on mine
 

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Those don't look like K&N filters, if they happen to have the lip inside that blocks the quarter-moon shaped port in the edge of the carb throat, that can be a problem.

Uni, Emgo, or K&N are three filters that don't create this problem.

Hard to tell from the pic angle, but the one filter looks set pretty deep on the carb. It might help to loosen and slide it back some, to help air flow at the moon port.

I do have an intact air box and ducts laying around. I'm running Uni PK92 pods without a rejet, no sweat, no stink, on stock pipes. :)

The port is at the top, air bleeds at the bottom also need air flow.

 

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269 Posts
As everyone has stated, all situations are different. I came across this site which addresses the different configurations possible in the intake/exhaust systems and gives a starting place. This is http://motorcyclecarbs.com/Motorcycle_Carburetor_Jetting__W7.cfm My set up is similar to MichiganTeddy's but I had drilled 4- 5/16" holes in each of the baffles. Like others have said in the first page, make sure everything is in order ( hoses ran correctly, taps plugged tightly) first. I'd do a spray seafoam treatment, then sync carbs first. See how it rides and go from there. And only change one thing at a time, then test the results.
 

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Soul Rider
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7 Posts
Discussion Starter #20
Wow! Thank you everyone. I will check the tubes and look into the "shaving" aspect. I'm not that mechanically inclined so i am still learning what A lot of the terms mean. So I should keep the same filters on and look at the things around it?
 
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