Mercury vacuum gauges, as used on multi cylinder motorcycles.

Its basically 4 rod vacuum gauges affixed side by side. You attach the line
to the provided vacuum ports on the carbs (behind the throttle plates), then
while running the engine, adjust the plate(s) so that all 3 gauges read the
same.

Adjust curb idle as needed...done.

Check you local motorcycle tool shop.

--
"Do or do not...there is no try"

Yoda- 1981
"Jeepers" wrote in message
...
Could someone have pity on me and point me to some kind of resource
describing how to sync three carbs.

I goofed and turned the screws on my Force 85's carbs instead of the
manifold mounting screws (long story, suffice it to say I wasn't paying
attention). I heard something about listening through a hose or
something once before, but I have no idea what I'd be listening for. I'm
handy with tools and have a workshop (I live on a ranch, it's a
necessity). I've worked on pletny of things from shredders to tractors
and Jeeps and lawn mowers, but none of them have 3 carbs!