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Discussion Starter #1
:rockon:Hell yeah pulling the carbs was fun!:rockon: I wish I had another vn here so I could do it all over again. Dude there is no reason in a sane world to have a setup like that. The air box must die. I will sell this thing before I try to jam the carbs back in with the stock system. So now is the time to shave, jet and coaster. So I know that there is tons of info in the v.v. to get me through this. Was just wondering if there is a one stop shop now to get everything needed in one box. Online stores come and go everyday so I thought I might get lucky. Also, Im leaving the belly in place for now so would that affect jet size? Oh yeah, one more thing; The vac/vent lines that t off the carbs and go into the air valves, what do I do with that? Cap off or vent into atmosphere?
Thanks in advance for all the advice you care to part with!:smiley_th
 

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Discussion Starter #2
One more thing. Will some one make sense of the whole needle thing in the ear shave file in the v.v.? A needle and a jet are one and the same right? They go back and fourth with shim this shim that, put it on top, no put it under, use factory needles, no use aftermarket, no they are too long, and on and on. Please explain.
 

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I Challenge anyone to

Fab a intake manifold for one Mikuni pumper for our VN's I agree with your frustrations on the design of the air box/cleaners/carbs. All my crap is in a box in my garage.
 

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Discussion Starter #4
Fab a intake manifold for one Mikuni pumper for our VN's I agree with your frustrations on the design of the air box/cleaners/carbs. All my crap is in a box in my garage.
I was thinking more like a holley projection unit. No springs, jets, shims, floats or other antique hardware. Just a throttle body with an injector. Maybe thats how Ill make my million. :beerchug:
 

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Discussion Starter #5
Alright, I just took the carbs apart for cleaning so I have been able to answer most of my questions. 140 for front and 142 for rear seems to be the most popular with shaving. Is that a good combo using a stock exhaust?
 

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Discussion Starter #7
they guy was on the right track with that. interesting read. It just shouldnt be that difficult to fab a simple throttle body with a mass air flow sensor in front and an injector in the rear. the control unit itself might be the problem but surely there is something already available that could be adopted and intergrated.
 

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Discussion Starter #8 (Edited)
Okay, I have shaved and jetted with 40 pilots, 142 mains, stock needles. Also coastered and replaced the leaking petcock with a new one. She starts up and runs fine. But after about 10 minutes it just dies. Doesent stumble or falter just dies. Have to fight and fuss but im usually able to restart. During one of the times that it ran for this brief duration I turned petcock to the off position, IT RAN FOR ANOTHER 10 MINUTES. Thats abnormal is it not? Also noticed that if I disconect the carb to petcock vac line the rpm goes up. So after turning it over several times tonight to try to get it to restart I have fuel coming out the front airfilter. I have cleaned the carbs twice and was so sure that I did not have stuck floats. HELP! P.S. Consider if carbs could be "loading" up due to 142 mains with stock needle.?
 

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Did you shim the needles??
 

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Discussion Starter #10
No I did not shim. I was going to but I have seen so many posts of people that have had luck with using stock needles w/o shims. I should add that when it runs, it purrs like a kitten. Smooth idle and acceleration.
 

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if is not the float needles, then it would have to be the plumbing. Those are the only 2 things that can cause gas to pour out of the carbs. Was the new petcock really new one or a "new to you" but used one?
 

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Discussion Starter #12
The petcock was a brand new in the box kawi but im sure its defective. After I gave up working on it last night I left the petcock to the on position. I was here all day painting the house and all was fine. However around two or three o'clock I looked at the bike and found that it had pissed all over the floor. Fuel was leaking at a steady rate from the front air filter. I turned the petcock to off and the leak stopped. (Carport where the bike lives faces west so the sun was shinning directly on the tank) So, Im going to have to assume that the light had warmed the tank pushing fuel through a petcock that is not operatating as it should. Sound right?
 

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Does the petcock have a "prime" (older style)? If not, then the vacume valve should have prevented and gas from leaking and the petcock is bad.

Was the bike on the center stand and how full was the tank? You also may have a bad float needle or the float hight is not correct because the float should seal good enough to stop any gas from leaking

If the sun really warmed up the tank causing pressure to build up, you have a plugged tank vent. My tank will sing in that case unless it is really full.
 

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Discussion Starter #14
No the valve was newer style. And appearently defective from jump. But im stumped on the float valve. When I took it apart I checked it by blowing air into the port while rasing and lowering the float. It was working fine.
I would guess it would have had to been the sun warming the fuel. It sat for 16 hours without a problem. Heat is all I could come up with. However the vent tube is clear through the hose to under the gas cap
i dunno
 

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Check the valve seats for the float as well as the rubber part on the valves themselves. If there is a wear groove in the valves or if the valve seats are damaged even slightly, the float valves will not seal and can cause your problem, though the petcock sounds bad as well. May be a two fold problem.
 

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Discussion Starter #16
strangely enough, the petcock is working as it should today. go figure. the bike was in the mood to run today but it is fuel fouling the plugs and is passing grey smoke. I set the a/f to two turns. Back down to 1 3/4?
 

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Discussion Starter #18
:rockon:nothin like it!:rockon:
Get you some of that airbox and you will love it
 
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