Carburetor confusion!

I'm not confused. OP could only find XS400 carb kits, when a link to XS650 Parts, (includes XS650 carb kits by turning a page), was posted, (I thought a person with a 40 year old bike would be interested in a retailer who sell parts for the bike), he searched for XS400 carb kits using the link for XS650 Carb kits.

But it doesn't matter because once the float needle valve set is replaced, the bike will never need anything else.
That retailer is looks decent and I'll probably use them in the future to get some things. I found an alternative that works better for me at the moment, like I said before I do appreciate what you've said because now I know what I can use to get this bike up an running quicker
 
I'm not confused. OP could only find XS400 carb kits, when a link to XS650 Parts, (includes XS650 carb kits by turning a page), was posted, (I thought a person with a 40 year old bike would be interested in a retailer who sell parts for the bike), he searched for XS400 carb kits using the link for XS650 Carb kits.

But it doesn't matter because once the float needle valve set is replaced, the bike will never need anything else.

No one said you were confused…



… maybe you are confused haha. Just messin with ya.
 
The guy I got the bike from cleaned the carb out along with a few other things. With that being said the inside of the carb is honestly the cleanest ones I've seen. There's no rust on the inside anywhere and the jets themselves are spotless, that's what led me to believe getting a new float valve along with a few other things that come with the kit would fix my problem. Again the problem I'm having is the carb is dumping fuel into the intake
If it's overflowing, the float level may be too high, the needle valve could be worn out or there could be some debris preventing the needle from sealing. I'd start with lowering the float level slightly by bending the tab that contacts the float needle.
Also, with the carb off the cylinder but with the fuel line connected, and holding the carb at the same angle it sits when on the bike, turn on the fuel and see if it overflows.
And of course, make sure you have good flow from the petcock.
As far as, "The guy cleaned the carb out." That means nothing. Until you have properly cleaned the carb you don't know whether it's clean or not.
More likely, he tried to clean the carb, the bike still didn't run properly so he sold it to you. Don't believe anything that anyone says until you've personally confirmed it.
 
If it's overflowing, the float level may be too high, the needle valve could be worn out or there could be some debris preventing the needle from sealing. I'd start with lowering the float level slightly by bending the tab that contacts the float needle.
Also, with the carb off the cylinder but with the fuel line connected, and holding the carb at the same angle it sits when on the bike, turn on the fuel and see if it overflows.
And of course, make sure you have good flow from the petcock.
As far as, "The guy cleaned the carb out." That means nothing. Until you have properly cleaned the carb you don't know whether it's clean or not.
More likely, he tried to clean the carb, the bike still didn't run properly so he sold it to you. Don't believe anything that anyone says until you've personally confirmed it.

Float heights are provided by the factory and have a spec.

They are not arbitrary, not to be raised and lowered just cause. Measure, adjust if needed.

I’d put money on 8/10 carb over flowing problems belong a worn needle/seat or a stuck needle.
 
If it's overflowing, the float level may be too high, the needle valve could be worn out or there could be some debris preventing the needle from sealing. I'd start with lowering the float level slightly by bending the tab that contacts the float needle.
Also, with the carb off the cylinder but with the fuel line connected, and holding the carb at the same angle it sits when on the bike, turn on the fuel and see if it overflows.
And of course, make sure you have good flow from the petcock.
As far as, "The guy cleaned the carb out." That means nothing. Until you have properly cleaned the carb you don't know whether it's clean or not.
More likely, he tried to clean the carb, the bike still didn't run properly so he sold it to you. Don't believe anything that anyone says until you've personally confirmed it.
I took the carb apart myself to confirm and like I said before the jets, bowl and float were honestly spotless. That's what leads me to believe the float valve might be bad. I went ahead and got the kit anyway to go ahead and replace the bad things, anything I have left or still good I'll tuck away for the future. As for the petcock it seems to have good flow and the tank doesn't look bad, it probably wouldn't hurt to clean it anyway though.. I do personally check behind anything I haven't done myself just because you can't believe anyone these days lol
 
Float heights are provided by the factory and have a spec.

They are not arbitrary, not to be raised and lowered just cause. Measure, adjust if needed.

I’d put money on 8/10 carb over flowing problems belong a worn needle/seat or a stuck needle.
Got one on the way 🤙
 
That's what leads me to believe the float valve might be bad.
Easy enough to check. Hook a fuel line to the carb, remove the float bowl, verify good flow, then push the float up and flow should stop.
That's the first check I do if I suspect a bad needle.
 
Might help to install some in-line filters also. Even if the tank looks clean it could have some debris. Nothing like getting a little garbage in the needle seat to ruin a good day.
 
Easy enough to check. Hook a fuel line to the carb, remove the float bowl, verify good flow, then push the float up and flow should stop.
That's the first check I do if I suspect a bad needle.
I'll have to try that just to be sure, I appreciate it!
 
I'll have to try that just to be sure, I appreciate it!
In that case... more in depth....
Push the float closed gently.... imagine you're the fuel level pushing it up..... not much force there.
Then I take a blow gun and (again gently) blow the whole bottom dry.
Hold it there for a few minutes and see if there's any fuel residue starting to form around the needle area.
If it stays dry for a few minutes, you're golden.
 
In that case... more in depth....
Push the float closed gently.... imagine you're the fuel level pushing it up..... not much force there.
Then I take a blow gun and (again gently) blow the whole bottom dry.
Hold it there for a few minutes and see if there's any fuel residue starting to form around the needle area.
If it stays dry for a few minutes, you're golden.
Alrighty, that sounds pretty simple, I'll definitely be careful with the float so not to stretch the prongs
 
Your bike should have viton rubber tipped float needles. They are very good, don't wear much, and usually last a long, long time. When you cleaned the carbs, did you remove the float needles from their seats and insure those seats were clean? There very well could be junk in them preventing them from closing properly and completely. Maybe it's just gas varnish build-up.
 
If there is any rust or debris in the tank it will find its way into small jets and orifices. If the carb looks spotless inside doesn't mean there isn't a blockage.
You also need to check the floats, they may look OK, but could still have small holes you can't see. Boil the kettle, fill a cup with the hot water and submerge the floats, you shouldn't see any bubbles.
There are only two gaskets on the carb, super easy to make yourself with a pair of. Cuticle scissors and hole punches.
Jets don't usually need to be replaced, they are a non wearing part, just clean and blow through with compressed air, same with the orifices in the carb body.
The only thing that may need replacing is the needle and seat. Although, many years ago I used to place needles in a drill, spin and face with fine wet and dry. Rubber faced needles will need to be replaced.
Cleanliness is next to good runningness, particularly the areas you can't see, blow through with compressed air.
Now we come to diaphragms: Diaphragms are reasonably cheap,in your part of the world, thanks to JBM industries, but, there is a better fix than replacing the diaphragms, it is called 'VM carbs'.
Carburettors are basically simple devices for metering an engines fuel and air requirements. Why anyone would need to add complexity to them is beyond me. Somebody should blows Mr CV up!
 
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