Disaster, broken Flywheel and stator.

My first question is about the flywheel is it balanced by it self or will a new flywheel mean that i will pull the Engine apart and balace Everything?

Now for the background story.
Had just replaced my RR for a new Mosfet one.
Solderd every Connection an had a real good charge.
Riding and feelt good about myself and my Little mod then i noticed that i the voltmeter showed just over 12volts wtf. okay just a Little bit furter lies my destination.
I belive the remaining bolt for the alternator cover fell out at this Point.
a HORRIBLE rattle and the smell of burnt plastic looked down.
The alternator cover was still there but just because it was stuck on one of the remaining guides, but just by a hair.
But behind it was carnage.
Bits of magnets bits of the stator looked like you had beaten the crap out of Everything.
The only thing i could do was remove the alternator cover completly and Clean out the worst of the crap from the flywheel and slowly drive home.
I made it home btw.

Sad day none the less. long weekend ahead and no bike.
But does anyone know if i just can replace the flywheel or if i will have to balance the whole assembly?
(crankshaft and so forth)

Best regards H

Kawasaki, Harley, or Schwinn?

Kawasaki KZ750 E1 1980

I would think each rotor is balanced before mounting it on a crankshaft. If the motor was being rebuilt and the crank was easily accessed, sure balance the 2 as a set. You should be ok just mounting the rotor to the crank. Just be sure to torque it to specs. I do not have a service manual near me at the moment.
Sorry to hear of your ruined weekend.

I took a quick look at the parts diagrams and pictures I could find. It appears that the flywheels are all independently balanced. I can't say for sure. Are you sure your flywheel is actually toast. or is it just a lot of damage to the stator?

No balancing required, just make sure you didnt bang up end of crankshaft.

Yeah the flywheel is toast.
Try to use your stator and flywheel assembly as a drum brake then you will have a good idea of the carnage.
We are talking shattered magnets whith missing pieces.

I rely hope that the crank is okay since that truly would be a devastating blow.
I have found evething i need here in Sweden but it will set me back about 300$
The flywheel is NOS.

I haven't decided yet though.
I know I can find cheaper on Ebay but then it will be a used part in unknown condition.
and take forever to get here.
btw I am talking about the flywheel now.

Now just to find new bolts for the alternator cover and some locktite (they will not vibrate out again on me that is for sure)
Thanks for putting my mind at ease regarding balancing btw.

Best Regards H