Carbs d@#m pos!!

[bikerphil]

Sending you a PM...

[cywelchjr]

Yes, I put in new fuel needles and seats from my K&L kits, still got gas flowing out the carbs and into the motor, Floats set exact, checked for float leaks, none detected, just gas pouring into the motor and good oil. I am feed up with these carbs and will do what ever to get them to stop pouring gas into my motor

Make sure that with the bowls off, that you can blow into the vent lines and get air going into the carb bowl area. If the vents are for ANY reason blocked the carbs will overflow, and as long as their blocked nothing else you do will stop them from overflowing. One person had the gas and vent T's swapped, the larger ones go on the bottom, and if you get them swapped they are likely to block the vents and cause the carbs to overflow.

Just something to check if their overflowing and you can't find anything else wrong.

[XS1100_OEM4ME]

Vent lines?

Make sure that with the bowls off, that you can blow into the vent lines and get air going into the carb bowl area. If the vents are for ANY reason blocked the carbs will overflow, and as long as their blocked nothing else you do will stop them from overflowing. One person had the gas and vent T's swapped, the larger ones go on the bottom, and if you get them swapped they are likely to block the vents and cause the carbs to overflow.

Just something to check if their overflowing and you can't find anything else wrong.

What do you mean by "vent lines" I have two "run" lines and two "prim" lines, one octy vac line, thats all the "lines" I have to the carbs What are the "vent lines" on a 79xs1100 special

[bikerphil]

On the T's between the carbs, the upper two are bowl vents that go back to the nipples on the airbox. The lower two are the fuel inlets. If you were using the upper T's as fuel inlets, that would for sure cause a flooding condition.

[DGXSER]

Are you certain you have 78-79 carbs? It is not uncommon at all for folks to mix and match carbs with years and models.

If you have the later carbs, there is only two Ts total between the cabs. The 78-79 models have four Ts total, two lower for fuel, and two upper for vents. Another way to check is to see if there are three or four holes in the inlet bell side of the carbs, the fourth hole was added in the 80 model carbs as a vent, eliminating the need for the upper vent T.

[bikerphil]

[Ken Talbot]

What do you mean by "vent lines" I have two "run" lines and two "prim" lines, one octy vac line, thats all the "lines" I have to the carbs What are the "vent lines" on a 79xs1100 special

Sounds like you've indentified the problem. The upper "T" between the carbs on '78 and '79 models are atmospheric vents for the float bowls. If you plumb gas into hem, you get flooding.

[XS1100_OEM4ME]

confused

confused

On the T's between the carbs, the upper two are bowl vents that go back to the nipples on the airbox. The lower two are the fuel inlets. If you were using the upper T's as fuel inlets, that would for sure cause a flooding condition.

Ok, my carbs have 2 "T's" between the bowl's of #1&#2 and #3&#4 carbs, those hoeses go to the octy then to the "run" setting on the petcock, but have a "t" fitting that goes to the "prim" on the petcock, what is this vents / nnipples

[bikerphil]

The 2 upper T's run directly to the 2 ports on the airbox, these are your bowl vents. The lower 2 T's run to the octy hoses as in the above diagram.

[bikerphil]

[petejw]

hi XS1100_OEM4ME,

heres a link to wildkats excellent write up on carbs,

http://www.xs11.com/forum/showthread...ight=carbs+101

on the front page are pics of the late model carbs (sorry i couldnt find
any early model pics)
if ur carbs dont look like these then u have the early
model carbs.

and as the others have said, if u have the early model carbs
the upper t's need to be either vented to the air or attached
to the air box as in phils pic.

[XS1100_OEM4ME]

Carbs

Are you certain you have 78-79 carbs? It is not uncommon at all for folks to mix and match carbs with years and models.

If you have the later carbs, there is only two Ts total between the cabs. The 78-79 models have four Ts total, two lower for fuel, and two upper for vents. Another way to check is to see if there are three or four holes in the inlet bell side of the carbs, the fourth hole was added in the 80 model carbs as a vent, eliminating the need for the upper vent T.

Not sure after reading your post to the year of the carbs, though OEM for 1979 xs1100 special, brass floats, meaning 79 and before carbs, only lines are two "T's" from the bowles feeding the needle valves, they go to the octy and all the prim / T / petcock set up is OEM by the book and all the under seat / clymer / yamaha spec. No upper "T's" going to air filter from carbs No yamaha spec or clymers man or anything else shows that

[petejw]

can u take a pic of ur carbs?
they sound like the early model, but they're
all fitted with vent 't's.

[bikerphil]

Lon, your carbs should have this setup, "A" being the vent and "B" being the fuel inlet. You should have these T's between carbs 1&2 and 3&4. The octy only hooks to "B".

[natemoen]

And A is a vent that hooks to the airbox or at least is open to atmosphere.