Carb sync, no reading on Carbtune

[Steve]

Use #3 as the master carb and adjust it using the idle adjustment knob at around 1 1/2 to 2 turns in.

If he still has stock carbs on his '77 bike, they are VM carbs, so there is no "master" carb.

Also, when you make an adjustment on the VM carbs, the vacuum levels don't jump around as much as they do on the BS carbs. It's pretty much that one carb's vacuum level moves toward the others and they change a little bit (all together) to meet the one you are changing. Makes adjusting the VMs a bit easier and quicker.

.

[JTGS850GL]

Sorry, missed the year. Sometimes I get stuck on CV carbs in my mind. Thanks for the clarification.

[Gorminrider]

This might seem a stupid question, ignore if you have done this but do you have compression in the low cylinders? (per your mention of cold cylinders) No compression=no vacuum...and it's a good idea to check and set valves before sync.

[hannibal]

I've checked valve clearances and changed shims to bring it into spec. I have not done a compression test. The bike ran decently when I bought it so I assume compression is good.

[Gorminrider]

how is it going?.......thumb on a spark plug hole is a sort of test too...hand cranking

[hannibal]

I have not had time to work on it unfortunately.