How do you tell when a VOES switch is going bad or gone bad???
I am at the end of my rope trying to figure out why my scoot is running like doo-doo.
I just installed a new Mikuni 42 because my other carb was junk and figured my problem would be solved but NOOOO.
It starts and idlles the best it ever has but it spits and backfires though the carb wicked bad until it warms way up which is something that never happened before.
When it warms up for about 5 minutes it is almost my a switch is thrown and the idle picks up a little and then is responsive to the throttle.
Someone please help me.

one more thing. It appears that the epoxy that the ignition pik up is encased in is real soft and almost melting.????????

Thanks in advance
Joe

 

Sounds like a vacuum leak around the carb or manifold to me. Make sure the vacuum port on the Mikuni is in use or capped, and that you have no other leaks anywhere, including the spigot o-ring.

 

I replaced the manifold gaskets and did the wd-40 test and everything seems fine.
Give me back the old days when all you needed was a set of blue streak points and condenser in your pocket and go anywhere. ho needs a starter?

 

The epoxy should not be "real soft", I think you found your problem as long as there are no vacum leaks. Hope this helps

 

sounds like there is a leak/chang the voes/farting through the carb and pipes might have to rejet it/if the intake seals are not put in right you might be sucking air/had the same problem/when it gets hot things swell.

 

There is nothing that could malfunction in the VOES that would cause those symptoms. That being said if the VOES was cracked and leaking air then you could have those symptoms. Take the VOES off and inspect it and while you are at it replace the hose and inspect the tee.

 

Backfiring through the carb is a lean condition. You gotta confirm no vacuum/air leaks. If none are found, I'd try jetting up on the slow speed jet or adjusting the mixture screw if the Mikuni has one. It's going lean for some reason. Trying to remember(I removed my VOES switch) but isn't it basically like a vacuum advance on old cars? This shouldn't cause the problem you're describing unless the hose going into it is split or leaking.

 

the ol girl is back up and running! running great as a matter of fact.don't know what I did.
I did A VACUUM test and the v oes was fine. checked every electric connection and went one main jet size smaller in the mikuni and adjusted accelerator pump starting point.
I fired it up and low and behold she came to life with a roar.
Thanks to all who offered help and opinions.
Joe

 

Glad to hear you found the problem.

 

And like John sez, you'd better be shopping for a sensor plate, 'cause you ain't got much time left on that one.