vacuum petcock thought

[Nolzb]

I have noticed that my bike does not like to run on vac/ the on setting on my petcock so I always used prime. However the other day I noticed that only one of the vacuum lines from the nipple of the intakes/carb joints is hooking up to the petcock(because there is only one line to do so) to produce the vacuum. Question is, do I need to have a tee so I can have both nipples connected from the intakes and then have the single line to the petcock to produce better vac to pull more fuel... i.e does only one intake suck hard enough for the vacuum setting on these petcocks. Apologies for being long winded/confusing.

 

[BBS360]

Either one should work fine. No need to tee.

 

[Nolzb]

Huh, weird. Thank you!

 

[amc49]

If the engine is older the vacuum drops off anyway. Running petcock on prime is fine as long as you turn it off at bike sitting to prevent possible flooding and hydrolock to destroy the motor. A skill all bikers should learn anyway.