I have problem with starter motor, no longer cranks the engine but
makes a buzzing sound at starter relay. The relay is good, I took it out and checked it on bench, it picks and holds(no load) but when
starter lead wire is connected to the relay upon start the relay buzzes and the starter motor not cranking the engine.
Is there a way to check the starter motor without actually remove it from engine?
The problem happened right after I added fluide to the drained clutch cylinders, the engine goes in nutral OK, seem unrelated to me.
Also the wiring diagram shows a circuit breaker in path, I could not find a circuit breaker in vicinity of fuse box and the starter motor relay, anyone knows if S50 indeed has a circuit breaker and it´s location?

 

I actually am dealing with this same exact problem right now.

I did find that the fuse box is on the left hand side of the bike underneath the cover there.