Unknown hose connector underneath Carburetor #3

[SWK-Valk1520]

Dear Valkies,

I'm a new owner of my awesome 1997 Bumblebee Valkyrie and last night while I was doing an oil and coolant change on my Valkyrie, I noticed a seemingly unplugged hose connector at the bottom of the carburetor #3... I have attached a photo of it here for your kind review.

Does anyone know what this is? I couldn't find any hanging hose for this.

Thanks!

[98valk]

california model carbs have extra vacuum port connections for the epa charcoal canister system.

[Mooskee]

That is one of 7 extra vacuum ports that are on California carbs. Given that the background in the picture shows the PAIR reed valve assembly, the bike is probably not desmogged. That means that that port should have a vacuum hose connected to it. As mentioned above, it looks to have been missing for a while. Look around under the carbs and see if you can locate a loose vacuum line. I think it is the one that goes to the vacuum canister. If you can find it , reconnect it.
 
If you are backfiring on deceleration, this is at least part of the reason why. When you let off the throttle it causes a vacuum spike. If there is a vacuum leak it sucks in air and causes a lean condition. The lean condition causes afterburn in the exhaust.

Here is how to identify California model carbs:
https://img1.wsimg.com/blobby/go/70754328-6fc6-422f-89c5-60bb891503fe/downloads/afbd5b91-62e7-4ddc-8609-522b67b409fa/Desmog%20-%20How%20to%20Identify%20California%20or%2049%20Stat.pdf?ver=1787001603576

If you need more input feel free to post here or email me mooskee@valkyriecarbsandcustom. I will pull together the info you need. It is hard to attach documents to the forum.

Dave

[John Schmidt]

Yup, Mexifornia type carbs that use the extra tube like was explained. I've had two different sets of carbs on two different bikes, one set I simply blocked them off since the bike was desmoged. The other set I had professionally rebuilt and they were tapped and sealed off with a small bolt/screw. Neither bike was a California bike, just the carbs were from a Cali bike.

[Hook#3287]

I thought that was a foreign bike.

I was right, it's Californian.

[SWK-Valk1520]

Thanks Guys for your inputs!

I have also noticed that my Valkyrie do have a canister installed in front of my rear wheel, so mine is the California model...

I will give it a thorough look for any loosened vacuum tube hanging underneath the hoses forest this weekend, and @dave you are spot on about the deceleration pop... It is quite significant with the pop, but no bangs. I've planned to take a leak check on the exhaust and intakes, and I will include to do investigation on this tube port at carb #3, too.