Other carb questions

[newmaac]

On an 80 Special, can anyone tell me the significance of the O-ring that is on the Outside of the seat on the needle/seat assembly.
The importence of the rubber tip on the needle is obvious, but I don't understand why the seat basket needs to seal well with the carb body.
I replaced the needles once, several years ago, and the still look good,
but the o-rings are completely flat on the outside and the seats easily slip out of the body, once the screw and retainer is removed.

Will there be any difference in actual performance if I were to buy new needle/seat assemblies?
(the dealer doesn't sell just the o-ring, or even just the seat. it's all or nothing)

Thanks in advance

[bikerphil]

If the O-ring is bad your carbs will flood. Since the seat is not a pressed in/interference fit, it requires some sort of gasket. Fuel should only be aloud to flow thru the center of the seat, not around the sides. That would defeat the purpose of the shut off needle valve, no? Go to your local Harbor Freight and buy the nitrile O-ring set for $6, it will have the seat O-rings and even the tiny ones for the mixture screws.

[Bonz]

Yes, important o-ring. They aged on my 80SG, causing the dreaded fuel in the airbox syndrome.

It's important to know they should be a pretty tight fit, should make you put some muscle behind pulling them out and pushing them in. If they seem to go in or come out "easy", they have seen better days.

[newmaac]

thanks

Sweet. You guys rock!!
This site is awesome. I've been away too long!