Dellorto VHB rebuild

[Turin]

It's been 20 years since I cleaned these carbs. (the ambo sat for a few years). Last time, I didn't do the best job and I found 2 instances of cobbing.
Here's the question... Do the idle screw and the mixture screw get O-rings and gaskets? None were present but I see them on the exploded parts diagram.

[guzzisteve]

None that I have seen or replaced.

[John A]

I vaguely recall that there was a Delorto service bulletin that said you could use them on the mixture screw if you wanted. Just add the washer and and o ring,the mixture screw remained the same.

[Antietam Classic Cycle]

None of the Guzzi VHBs ever came with them.

[Turin]

Then I'm not crazy. Thanks!

[John A]

Then I'm not crazy. Thanks!

That’s a bold statement from someone that rides a Guzzi! 

[John A]

None of the Guzzi VHBs ever came with them.

 Yep, I first saw them on PHF’s. You can put them on VHB’s, it’s optional. As I recall there were no other changes needed to use them. There were two reasons, one was it could pull air in around the mixture screw and to help the screw stay in place. I’ve never had one move out of adjustment, maybe on a dirt bike it would make sense.