J&P Cycles Motorcycle Community

can someone pls explain what the hell a VOES switch is, what it's used for, where it sits on the motor, and whether an Evo motor uses/needs one ? (go easy on me - i'm a first time builder) THANX

If you go with a slide body carb or electronic ignition, you then ditch the VOES.

More details: The voes switch closes when there is high vacuum, when it closes the timing is advanced. So when you wack open the throttle, haul a load up hill or at idle when there is low vacuum, the timing is retarded. When you are cruising ( and vacuum is high) the timing is advanced for better economy. There are a number of switches available that will close at various amounts of vacuum ( in inches of mercury) from the dealer. The voes usually mounts over top of the intake manifold and gets the vacuum signal from a port on a CV carb or from a port on the manifold. I use them on my bikes. MK

so... running an S&S Super G carb with a Forcewinder DOES NOT require a VOES ?!!!? right? it's a butterfly carb w/ a constant/fixed venturi. ok, well then... to quote Remus' "How To Build The Ultimate V-Twin Engine": "Instead of a choke an enrichment circuit is used." WHAT THE HELL ARE THEY TALKING ABOUT NOW?!!? what KIND of circuit are we talking about here and am i confusing THIS for the VOES (that apparently i DON'T need w/ a G carb???!!!???)

the enricher is nothing but a different way of choking the engine for starting. dont get it confused with the vos thing.

the enrichner basically dumps fuel into the carb. through a different chamber in the carb. not to be confused w/ the voes but often confused with choke. the enrichner knob on newer bikes is marked choke.

Yes, you could be confusting the two. But they are unrelated. An enrichener and a choke are essentially the same thing. They are mechanical methods of 'enrichining' or rather, providing more fuel at startup, to facilitate firing. The VOES is an electronic switch actuated by carb (intake) pressure. This switch regulates timing based on the demands of these demands, of the intake. choke is for starting, voes is for timing. clear as mudd right?

leave the voes swith alone, it is there to prevent engine damage-if you need the instruction sheets for your s&sm carb, let me know, i have extras

thanks to ALL- steve, could definitely use those S&S carb sheets you have. lemme know the best way i can get those from you. thanks!

e-mail sfranta@jpcycles.com with a fax number or mailing address

How do the two different choke styles work? One is the butterfly style. It appears to reduce air flow, but the jets meter the normal amount of fuel; creating a fuel rich start condition. How does the CV "enrichener" work? PTL

instead of restricting the air, it increases the fuel, which eliminates the extra plate in the carb throat, which means better air flow hence better performance