MOPED ARMY

It's part of the carb. It helps atomize the fuel at a quarter throttle if I remember correctly.

looks like this:

see those little holes? air gets in there from a little hole inside the intakebe of the carb. a upgrade would be somthing like the same tube, but with bigger or more little holes in it.

It is an upgrade. If you have a 1977 carburetor speed kit for the stock 14.14 PHVA, it comes with a different emulsion tube, main jet, and idle jet. This emulsion tube is a little bigger than the stock one. Look at the numbers if you don't believe me. The stock one is a 209GA and the 1977 emulsion tube is a 210GA. Like what sabat said, the tiny holes allow the fuel to mix with air, making the gas easier to "emulsify" or "atomize" when going through the carb.

exactly nerobro thanks....

Emulsion tube there is three different types.... primary... bleed... and primary/bleed..... they screw into the main jet and with cards where there is a jet needle... needle in the slide with slips.... the nthe tube is referred to as a needle jet... they effect from... assuming its a mechanical slide carb with jet needle.... then it effects from 1/4 to3/4 throttle.... they really only matter because it doesnt matter how much bigger it is... if its the same size as main jet theres nothing to worry about.. bigger then main jet... wasting your time.... hope that helps with tuning....

they have different diameters... and yes tapers on the inside.... some will come with hoods on top as well... they work with cut away in the slide as well as atomize- which means... fuel suspended in air...

bump

2.20 ftw. use with a stock puch needle, check out the lines on the needle. four slots and two little stripes. compare to 15bing needle: 4 slots and one little line.