Idle screw setting?

I have had a lot of issues figuring out what is going on with my bike. Finally thought I had it and it started up and seemed to be finally running right. Took it out to test and made it two blocks before it was sputtering and trying to die. Finally wouldn't even start and was backfiring loudly just when cranking. Pushed it back.
I've messed with the idle screw so many times in the last few weeks that I no longer have any idea where it is "supposed" to be set. I know where the rpms should be when warm and idleing, but is there a start point I should put it back to? I have no idea why it started and ran in the garage and after some warm up only made it two blocks. I pulled the plugs, which are new, and cleaned them off after I pushed it back. First two were really black but dry. 3 and 4 were equally black but a little wet.
Before I try again I wanted to check where the idle screw 'normally' rests. Like how many turns from where it touches the metal part that gives it more throttle? Should it just be resting there? or giving it some throttle?

 

what bike? please update your signature with this info.. thx

 

Start with it just touching, and make sure throttle adjuster at handlebar is not wound out and resembles a piano wire. Fir bike up with choke and when warm close choke lever and tweak idle screw.

If every thing in order and well maintained you could just be flooding the engine?

If not you need to be prepared for some maintenance work and you need to get a service manual to supplement advice given.

 

My bike is an 82 Maxim 650. I do have the service manual but generally you adjust the idle screw after the bike is warm and carbs are all right and everything. I just needed a start point to go from. Thanks Capnredbeard, I will try it just touching to start. Could having the idle set too high have caused it to die, and then backfire a lot when trying to start? I warmed it for a minute or two, until I could turn the choke off without it dying. The idle seemed ok. But then it didn't make it two blocks. Is it possible it wasn't warm all the way but just stayed running because the Idle screw set too high?

 

Is it possible that you have a whole bunch of tight valves (in which case it ain't GONNA run?)

Starts up cold, then won't start once warm is a classic symptom of tight valves.

-Check valve clearances; get them in spec.
-Properly clean and service the carbs,
-WET-SET the float levels,
-Bench sync.
-Set pilots at 2 1/2 turns out.

Then you fire the bike up, and do your running vacuum sync, with YICS blocked.

A word of overall advice here: the bike (and its four, vacuum-controlled carbs) do NOT respond well to "messing with." You need to be precise, and do things thoroughly, completely and in order. Anything less will only lead to continued "problems."

If you have the service manual, all of the above procedures are in there; and we have all sorts of helpful stuff on this site to supplement the manual. Quit "messing" get serious, read the manual and let's get the bike FIXED.