So what does the VOES switch control or effect? for about the past week I noticed a louder than normal sucking sound from under the tank. Thought I had a Vacuum Leak. I decided to check and saw a vacuum Hose loose, removed the tank and the hose goes from the carb to the VOES switch.
So what does that switch actually do/ control?

 

It controls which advance curve the ignition module uses. Think of it as kind of like a vacuum advance mechanism, or a lack of vacuum retard mechanism.

 

This should pretty much explain everything.

http://www.wildwestcycle.com/f_voes.html