Topic: 500 Bench Sync Clarification

[riverfever]

Pardon my ignorance but...I've searched on here and just want to make sure I'm doing this the right way. On Youtube I see people are describing the process but they are making sure the butterfly valve is opening the same amount. But when I operate the carbs, the only thing that opens those up is the choke. I'm sure these need to be adjusted as closely as possible but I don't think this is what I want to do for the bench sync. So now I'm thinking that what I am adjusting is the part that holds the needle and slides through the carb body. These individual sliders are adjusted by the slotted screws that have locknuts. Then I need to ask, am I inserting an 1/8" drill bit between the sliding valve and the carb body on the side of the butterfly choke valve or the side that mounts to the motor? I would ASSume it needs to be done on the side that mounts to the motor because the slides are more flat over there. 

[lucky]

The carb slides that goes up and down allow more or less air into the engine.
It is those slides that is what needs to be adjusted when you sync the carbs.

The choke butterflies are not involved.

[riverfever]

That's what I thought. Just wanted to double check. Thanks Lucky.

[riverfever]

I know these aren't cb500 carbs but why is this guy adjusting the butterfly valve and calling it a sync?

Motorcycle Carburetor bench sync

[lucky]

The video is about VACUUM operated carbs from a DOHC model.
When the person in the video says TOP he really means  bottom because he had the carbs turned upside down.

You must make sure the throttle can close all the way. Very important.
It does not matter if it is a slide operated throttle or a butterfly style valve.

As with any carb he has to make sure that all 4 butterflies open at the same time.
There is a small cut out in the butterfly to allow just enough air into the carb so that it can idle.

There are butterflies for throttle and there are butterflies for a choke.
It depends which carb you are talking about.

There is no reason to stick a wire or a drill bit into the edge of the butterfly to make this observation.