91 FLH Starting problems

[badbonz]

Bike was starting to run kind of rough. Put some new plugs and wires last year and has been running like a charm. All of a sudden bike didn't wanna start flooding out real quick. Let the cylinders dry off. Finally started her up and she was running rough during idle. Tried my adjustments but ran like "Potty mouth". Removed and rebuilt ss carb. Put carb needles back to factory settings to adjust. Now the bike starts running really rich. Getting backfiring flames out of my pipes and through the carb when during throttling and at start up. Any suggestions? Could it be an intake leak or a coil problem?

[Burnout]

Yes.

Check for vacuum leaks by dribbling some spray cleaner on the manifold joints while idling.
If the RPM changes you have a leak.

If you have not fouled the plugs it sounds like an ignition problem. Lots of possibilities power to the ignition, module, coil, plugs & wires.

Obscure possible cause, charging system problems, disable charging system and retest to verify.....

[harpwrench]

Maybe the VOES or vacuum hose, the ground wire could be broken at the terminal that's bolted to the head behind the horn.

[JW113]

1991. Jeez. Where to start?

I can only speak to what I would do, which is a complete inspection and maintenance to just about everything.

Rebuild the stock carb, adjust to factory specs.
Replace all vacuum hoses.
Test VOES for leaks. (they are classically known for leaks after "X" many years or miles)
Remove the carb and intake manifold, replace the seals and gaskets.
Replace the exhaust pipe gaskets.
Check the timing. Stock ignition pickup sensors (in the nose cone) are known to melt after this many years.

If all that does not resolve the issue, then check back in.

-JW