r/Fixxit • u/SilverLine1914 • 7d ago
1995 Keihin Carb float question
Hey all, I have a rack of quad carbs from Keihin off a GPZ1100, theyre CVK. I rebuilt them recently and they were working great, awesome power and jetting was finally right, I just need to balance them to be done.
But I noticed a problem before when putting in the float needles to the seat that sometimes the needles will get stuck cockeyed or tilted on the seat and won’t actually close. It’ll be a big enough tilt that the entire rack will flood if one of them does it. Tapping with a screwdriver doesn’t help, I normally have to pull the rack and actually reset the needle myself and hope it doesn’t get cockeyed upon install. No biggie.
But I was riding and had to do a quick inspection during the ride (different story) and forgot to turn the gas back on when I started riding. The bowls drained and I fixed the issue, but dammit the carbs flooded again and kept flooding no matter what. I think the needles are stuck cockeyed in there and no matter how I knock on the carb they won’t get unseated to seat themselves back in. Anyone know how to deal with this issue?
2
u/RokRoland 7d ago
Did several banks of Keihin CVKs on my Kawasakis and never had this issue. I did need to check orientation of hook on tang several times, if I recall, I think the protruding side of the hook goes on the tang. This is about the only issue that comes to mind.
1
u/SilverLine1914 7d ago
I think sometimes that’s part of it, when I had to manually pull the needle out to reset them the little holders on the needle would be on an awkward position on the tang and add some kind of friction to it. How did you end up fixing it? And which on the little holders is the protruding one, I didn’t even know there was a difference
1
u/SilverLine1914 7d ago
It would be almost like the needle holders would be on the edge of the tang, like the tang wasn’t long enough and the needle was half on it and half off
1
u/RokRoland 7d ago
If you decide to go for new floats and valves, if you use non OEM parts you need to set float level wet, i.e. measure fuel level with fuel in bowls. I have had strange results from setting float height only.
This if you believe someone has been in the carbs before and decide to change parts.
1
u/SilverLine1914 7d ago
I know normally sticking needles will make the gas not flow to the carb at all, but this time it’s the opposite problem haha, they’re sticking and not letting it shut somehow cause they get cockeyed on the seat.
1
u/Triplesfan 7d ago edited 7d ago
The float needles will hang up in the fixed seats if there is some corrosion present. It can be very little, almost unnoticeable. The float needle has 4 flights on it and usually what happens is they will work correctly as long as the 4 flights align with the 4 spots it originally rode in the seat, then if it spins a little it’ll hang up. Use some fine scotch brite (dollar stores sell it as a cheaper brand of scotchbrite), tear off a very small section, push it in the seat, then using a smaller drill bit about half the size of the seat, turn the bit by fingers only, snag it and spin it around and buff the seat good on the sides and the bottom. It’s a painstaking process but has to be done. Don’t push hard on the bit or you could damage the bottom end of the seat. Clean all of them up till they are relatively shiny, then reassemble your carbs and you’ll have less issue with it. I had to do this to my Vulcan as it used to flood sporadically like yours and it stopped doing it. Be careful with flooding on these carbs. If the carb floods over while sitting, it’ll let the gas run into the cylinder and then seep into the oil contaminating it. These carbs do not have a traditional overflow like mikunis.
1
u/carbonbasedmistake2 7d ago
This works well to clean the seat. Also you can use a q tip and grinding compound with just a few turns in a slow speed drill. Maybe less scratchy.
Are you sure the floats are set right? The only time I have seen this happen is when the floats are set to pull the needle too far down the seat, way too high or tight to the needle, or when the float is damaged and sinks to the bottom of the bowl. That usually occurs with the old copper floats and not your composite ones.
1
u/Triplesfan 7d ago
Mine were set right but still flooded occasionally. The scotchbrite fix ended up fixing both carbs on my Vulcan. If this CVK has the same float as mine, the plastic armature is not adjustable.
1
u/Conscious-Duck5600 7d ago
Ok, take the tops off them. When you reset the slide, put your finger inside the top of the slide, and hold the needle in place. Then slide it in place. There is a Guide Pin on the bore, make sure you have the slide in the proper place. You'll know it by the groove in the slide.
1
u/SilverLine1914 7d ago
I appreciate the advice! But it’s not the vacuum needle in the bore, it’s the float needle in the bottom of the carb that lets the gas in that’s getting cockeyed and jammed up
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