1989 yz 250 can you help?

hello
ive got this 89 yz 250 ,,,,it had a firing problem so i took the
stator cover off and there was a flywheel weight rivited to the rotor
i noticed the weight was loose took the rotor off ,had the stator tested with a multimeter and they( the shop that is )
welded the weight to the rotor .......................
i submitted a thread a few days ago it was moved but im
not sure where
i just wanted to aviod any future problems by putting this
rotor back on .it wasnt balenced
any advice would greatley be appreciated and thanks again
lee

i appreciate the help!!
i was just worried about the crank being out of balence and causing
enough of a vibration to damage somthing
but if a machine shop can balence the rotor i guess theres nothing
to worry about just didnt want to b out in the woods and this
thing come apart hey thanks again i preciate it!