Air Barb vs. No Barb: '78 Carb Holder

[muskallunge]

Now that I've got my first chop wired and fired I'm get as much info on dialing in the carbs. It's a '78 xs650 with bs38's. Pod filters with straight pipes. Have new mains and pilots of larger sizes coming but had a question about the air barbs that would have been used or stock vacuum petcocks. Will leaving them open affect my mixture? Saw that Mike's xs sells non barbed carb holders. Also heard about keeping them for fine tuning. What do you guys know? Thanks

 

[5twins]

You have to cap them or you'll have giant air leaks. They are nice to have, even if you're not using vacuum petcocks, so you can hook gauges to them to sync the carbs.

 

[azman857]

I connect the 2 ports with a length of vacuum line . Runs good. Balance by exhaust pulses.

 

[gggGary]

Check any used intakes CAREFULLY for cracks visually before install, after when idling, with carb cleaner, ether or I hear; propane also works. these tend to slow down the idle as the mixture gets too rich. Stay away from the cheap auto store vacuum caps they tend to crack and leak quite quickly. You have to put some sort of clips or a couple wraps of wire on the caps or a backfire will blow them right off the bike, sooner or later. A bit of small ID fuel tubing and a 5/16" ball bearing with wire wraps after works well. A bit blurry but you'll get the idea.

 

[muskallunge]

I'm guessing the ball bearing is in between the two clips inside the ID fuel hose?