Hello everyone,
I was going to go for a ride on my gs but I were not able to make it starter to crank fast enough to start the motorcycle.
Last time I started the machine by pushing it and it did some really fast 120km, stop and the next day 120km back.
Once it's hot it starts but the starter it's really slow.

The machine has been the test bed for a project and I used the starter a lot, so my initial suspicion where that the carbons on the starter are dead and I was going to buy a rebuild kit for the starter but decided to first run some checks:

Rule out the solenoid:
connect a 12 gauge cable from positive battery to the cable that goes to the starter (avoiding this way the solenoid), same situation, slow crank

Rule out the battery:
tester 12v and more than 10amp

Rule out the starter:
took out the starter and put the body of it in the battery negative and the positive in the positive of the battery: the starter runs freely ....

so I put back the starter, took out the plugs to rule out the compression, put the bike on neutral, put two batteries on parallel, connect the starter..... slow crank....

at this point I have two options:
1) some kind of mechanical damage on the starter/connection to the crankshaft or the engine itself (probably more possible the starter clutch as I said the machine happily went some 240km without hiccups).
2) starter is bad, it spins freely on connection to battery but it doesn't have enough power.

Let me know what do you think?
I'll start by disassembling the starter and check the carbons on it.

Update: I disassembled the starter and it did look nice, still plenty of carbons, throw a clean anyway, put back, same situation....

will have to take out the engine cover to check what's next...

It might be goats, when you have goats the starter just spins which might sound like it is slow.
HOWEVER:  before you do anything else try with a known good batterie -/ 12 volts is very low for  a battery. Should be around 12.6

Update:
Ran cable from negative to starter body and positive direct from battery to rule out bad grounding, same results.

Thanks BMF,
I will tripple check with another one.

I'll do some research on GOATS.

Question:
It is possible to have the GOATS problem and the motorcycle to run fine?

Update:
Rear wheel won't freely rotate with the bike on the center stand on first gear with the clutch pressed, and it should

And another update:
I took of the clutch power stator engine cover and the starter clutch spins freely clockwise and locks counter clock wise.
No residues of anything.
Everything is clean, gaskets looks nice, oil is not dirty, doesn't smell like gasoline.

My guess right now it is that the starter is somehow fried up.

did you pull off the left cover? how'd the gears look?

really nice, my new suspect are valve clearance.
oooor the starter is fried.
I did inspect the oil, and no particles.

More update, I took back the starter after checking a video and see how it jumps, I did not remember the starter to behave that way when I test it and now spins like dying even outside directly connected to battery.
I find odd for a starter to become fried.

All valves clearance were out of spec.
What a PITA to check and to change the valves shims.
Bike starts normally.