Hi splash, rear wheel off ground, slack is 1-3/4” at loosest point on chain. Measured at mid point of chain run.

What I do is this. Rotate wheel backwards. You’ll notice the lower run will raise & fall a little. You can push up on chain at different places & verify loosest spot also.

Put a dab of grease or loosest spot on a chain link to mark it.

Center of front sprocket is the rod adjustment plug. Center of rear sprocket is the rear axle. Stand back & look for center. That’s the measure point.

I put tape measure on floor, it will balance. Pull tape up & lock it. Tape will be between chain & tire.

Pull chain down firmly with finger. Sight chain to tape measure & record reading. Push chain up firmly with thumb & take reading. That is the play.

Pushing chain with all your strength only changes play slightly so you don’t need to worry about splitting hairs on how hard to push.

To adjust chain slacken both brake stay bolts. Loosen axle nut. Move axle. As needed. Tighten all Fasteners. Don’t forget to tighten brake stay bolts!! A
Check rear brake adjustment.

The chain will seem too loose. But that’s correct. If you remove rear Shocks you could move swing arm & observe how slack changes as swing arm moves.

Again on its wheels will still be 1-3/4” or close to it. Have heavy person sit on bike to compress Shocks after you take off jack. Now you can see why the 1-3/4 is correct.

Regarding your clutch, the way it’s adjusted now is not right. Check plug for rod & make sure adjustment screw is not rubbing.

Do what you want but my recommendation is get Barnett cable. Shop around & pay the shipping. Hang new cable & lube with motor oil overnight. Cut hole in baggie & tape to cable. Barnett is best in world bar none. It has swaged steel ends, not soldered.
We’ll go over adjustment again later.

It is normal to hear clutch parts move inside primary especially when on side stand motor stopped.

If it clicks from right side your cable did not have enough play during rod adjustment or the ball cam is worn out. Usually at center hole.