Carb sync

Ok I’ve got this ‘friend’ who completely messed up a perfectly well synced carb by winding the balance screw all over the place and totally lost track of where the balancing screw was originally set (not me obviously  ) Now the bike won’t turn over and the battery doesn’t hold enough charge to keep the starter chugging on. As a guide are there a set number of rotations on the screw that will get it somewhere near original? at least enough to get it firing again. Or will it be obvious enough with the carbtune tool and a battery with some juice

Thanks from a silly friend.

I've never tried it, but I suspect it might be obvious if you measure it while it's on the starter.

Could you not get it to start with a bit of throttle?

No idea how many turns in or out it normally is - on mine you barely have to move it a quarter turn to get it in sync.

Thanks ET, I suspect it probably just needs a new battery fitted to provide a bit more fiddling time before the battery loses charge. 

While waiting for the old battery to charge between attempts, the engine got cold and wanted some choke however with the choke on the sync gauges were not reading anything when pushing the starter, and the sync got more out of whack and the engine didn’t turn over, then the battery died....and down the rabbit hole it went.

As suggested in another’s post I’ll pop the carbs so off and visually balance them first, while I’m fitting new hoses and battery. 

Gwhizz

IIRC it's wind it all the way out and then it's 3 and a 1/2 turns. Remember that a weak/discharged battery will drop voltage when the starter button is pressed and the remaining voltage might not be enough to fire the coils!