I recommend 45 pilot 180 main, and about 2.5 to 3 turns on the mixture screw. It also helps if you get a EZ-JUST mixture screw, you can make adjustments using your fingers instead of fumbling with screwdrivers. Make sure you are doing it around the 900 rpm range.
One key indication of too lean is popping thru the air cleaner when suddenly opening the throttle or going down hill and it's popping away like popcorn in the microwave.
One key indication of too rich is poor sudden acceleration, such as hesitation.
If you need to do more 4 turns of the mixture screw it is highly advised to go to the next size jet, which would be a 48 pilot.
Also, it's never advised to go too rich because of cylinder wash down and carbon buildup. Not to mention it will make your bike REEK when running!
I've got a plain-Jane 883R pretty much stock except for the rejetting wiith a NOKH needle and EZ-JUST mixture and idle screws, got a 2ki ignition module, and a Voodoo 3 ohm DF coil with SE FAT wires. Right now I've got it set with a 45 pilot, stock 160 main, with 2.25 turns on the mixture screw. Runs like a charm.