Topic: Bench sync...

[John Galt]

What did you find to have best results for a bench sync? I know you still need to do a vacuum test, but you still need a starting point to get it running....

[orange550]

don't you just eyeball the tiny notches on the bottom of the slide? Make it so the notches are in the same position as each other? Then vac sync when it's running?

[MasterChief750]

use a 1/8 drill bit, adjust the #2 carb or the only permanent carb to the bit the adjust the rest of the slides to the bit, that will get it started then do a vac sync. make sure your slow jets are clean and clear or the sync will be a headache. i had one clogged and couldnt get it right until i fixed that

[John Galt]

I think you need to be a bit more precise. Maybe use a caliper.

[John Galt]

Yes, I heard the drill bit method. The above comment was meant for orange 550

[orange550]

One of my old manuals talks about adjusting the slides until you see a crack of daylight. Make 'em all the same.

I always assumed that super duper precision on the bench wasn't really needed since the vac sync was the true tell and you'd adjust it then anyway.

But maybe I'm being naive.

[John Galt]

Can't be anymore naive than I am....

[MasterChief750]

ive had my carbs apart 3 times(PD carbs on a 78 750) the drill bit has had it purring right off the bat, usually a little high on the idle but once you adjust that and syng the carbs you will be golden

[orange550]

Do you put the bit in the notch? And then maybe add a little extra idle rack screw before you start so you have some ability to back it off?

I'm gonna help a pal set his up and maybe I can get it closer to start off, then do the vac.

[MasterChief750]

thats what i have always done, has worked every time. just make it so the bit can easily slide in the slide cutout.