Noise coming from the front on the engine of my 2000 fatboy after battery went bad on the highway

your push rod lifters are bad or you may have bent a push rod

kinda sounds like engine is out of time

I haven't had any problems with the balancing system. If the noise is coming from the left side, check the primary chain adjustment/adjuster. If it's coming from the right side, check the cam shoes. The shoes went bad in my '04 Fatboy and whined like it had gear drive cams. Good luck!

with it lifted into the air all 4 tires off the ground place it in 4wd and run it and see it you find what wheel bearing is bad

driving in 4wd on hard surfaces produces what is known as torque wind up as the wheels cannot slip so the variations of distance going around corners , dips in the road etc place considerable strain on the transmission , transfer case , drive lines and diffs
that is why it is difficult to get out of 4wd unless you drive with 2 wheels on a grass verge to relieve that torque wind up
as for the noise check wheel bearings and the cv ("U") joint at that wheel as there appears a proble where the dog teeth in the hub are not engaging properly or are jumping out of engagement

The clicking may come from how fast the pistons are moving. An oil change would probably not be a bad idea. You could also try seafoam products to clear out carbon build up in your engine.

More then likely you have a bad front hub bearing assembly.Noise goes away when turn right less pressure on right wheel bad right front bearing.

Try inside the tach on the connector. But also remove your speed sensor on the transmission and clean it. They pick up metal chips from the trans and short out. Also, HD had a bunch of bad speedos around your year. They replaced them for free. Doubtful they will replace yours at this late date. You might end up buying a new speedo.

Is it full time or part time 4 wheel drive? You should check the front driveshaft u-joints.

make sure that your battery cables are clean and tight.