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Discussion Starter · #1 ·
Guys,



I just got done doing Larry's carb rebuild and installed them in a bike that hasn't been run in years. It fired up within seconds and seemed very responsive immediately. Then, it started running a little worse and is now a little slow on the response. It definitely needs some fine tuning, but I'd like some recommendations. Also, I am in the process of cleaning out the tank, so I only had a funnel with a fuel hose hooked up for my temp gas tank. Is it vital to how the bike runs to have all the vacuum hoses hooked up? So far, I only have the fuel line hooked up and don't know where most of the vacuum lines go. Any help would be much appreciated. Thanks!
 

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If you have a vacuum petcock it has to have that vacuum line hooked up or no (or very little) gas will get to the carbs.



You might also want to balance the carbs- almost a necessity if you've had them separated.
 

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It's not "vital", but it's very important.



There is a vacuum line that leads from the carbs to the fuel tank's petcock/fuel valve. If you are running with no tank, make sure you plug that vacuum line or else air will be getting into the backside of that carburetor without passing through the carb body's venturi. This will throw off your fuel to air ratio in one of your cylinders.
 

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Discussion Starter · #4 ·
Yeah, I don't have the tank hooked up at all. I know that I need to hook up the petcock vacuum hose and breather, but what can I do in the meantime? Do I just plug the angled nipple on the right carb? What about the two little nipples that are facing eachother next to the fuel rail? Thanks guys!
 

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Discussion Starter · #8 ·
I have another question as well while we're at it. How important is the tiny little washer the goes between the spring and the o-ring on the mixture screw. One of my carbs didn't have one and the other did. Where can I get one if it is important? Thanks again guys!
 

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What about the two little nipples that are facing eachother next to the fuel rail? Thanks guys!
You do not have to plug those. I can't remember exactly what they are for, if anything, but nothing connects to them as I recall.
 

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I have another question as well while we're at it. How important is the tiny little washer the goes between the spring and the o-ring on the mixture screw. One of my carbs didn't have one and the other did. Where can I get one if it is important? Thanks again guys!
VERY! Without that washer your spring will tear up the o-ring. Plus the wash helps even out the spring's pressure applied to the o-ring.



I personally have ever only seen them come with a full rebuild kit, but you could probably find something close enough at a good hardware store or on e-bay.
 

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The 2 little nipples that face each other are just vents to equalise atmospheric pressure. They shouldn't have hoses hooked up and they must be clear. The bowl overflow is the nipple on the bottom of each float bowl and should be hosed down to the cluster of hoses that drop in front of the rear wheel.



And +++ on that washer. Absolutely needed. Not sure if it's an orderable part but, as suggested, any washer with the right dims will do the job of protecting the o-ring.



And +++ on plugging the vac nipple on the right carb if you don't have it hooked up to the petcock. And it normally hooks up to the front nipple on the petcock by the way. The rear nipple is a vent/overflow and should be tubed with the others to exit in front of the rear wheel. If you decide to mod the vacuum petcock as described elsewhere on this site the vac nipple on the right carb will have to stay blocked off. And if you're going to keep the petcock as is you'll want ensure that it allows good flow when vacuum is applied to the the front nipple. A short length of hose and at least one lung are sufficient for that.



Either way, try to jam an inline filter into the equation while you're at it.



Satisfying though ain't it, when a derilect bike just fires right up like that?
 

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Discussion Starter · #13 ·
Thanks a bunch guys! As always, you're very helpful. I guess I'll pull out the mixture screws and take my tiny little washer to the hardware store to see how close I can get to another one. You guys are the best!
 

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Good luck and don't lose your sample washer!
 

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Discussion Starter · #15 ·
Crap...I drove all over and nobody has one that small. I can get it through the Honda shop, but I also have to buy the screw, spring, and oring as well and it wouldn't be in until the end of next week. Anybody know where else I could get one? Thanks!
 

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Not sure, you might find one in some old electronic items if you have any lying around,,old computers, tape decks, etc.



Just a guess, I know those type things usually have small washers in them, if they would be the right size or not? Who knows, you might get lucky.
 

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PM me your address and I'll have a look. Pretty sure I have a couple spare and I'd be happy to part with one. Unfortunately it wouldn't get mailed until Monday though. Let me know.



Cheers.
 

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I'll look through my old stuff too. I might have one. *crossing fingers*
 
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